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| PRIMERS AND PRESSURE
|PRIMERS AND PRESSURE
by James Calhoon
(First Printed in Varmint Hunter Magazine, October, 1995)
In the course of talking to many shooters, it has become clear to me that the manufacturers of primers have done a less than adequate job of educating reloaders on the application of their primers. Everybody seems to realize that some primers are "hotter" than others and some seem to shoot better for them than others, but few reloaders know that primers have different pressure tolerances.
I ran into this problem myself when loading a 223 to the maximum. The primer I was using was piercing before the case began expanding at the head or reaching maximum pressure. How do you check maximum pressure without a laboratory pressure gun, you ask? To check maximum pressure on a given powder / bullet combination, measure the rim of the cartridge (at a specific point each time of the measurement) before and after firing. Cases don
Posted by Vince on Sunday, March 06, 2011 (18:53:46) (764 reads)
comments? | | Score: 1
| Essential information for new handloaders!
|by Mike Hines
I seem to see the same kind of question over and over again in the online forums that are about reloading your own ammunition.
Posted by Pumpkinslinger on Friday, March 26, 2010 (18:48:57) (1041 reads)
comments? | | Score: 5
| Civil War style paper cartridges
|Paper cartridges for muzzle loaders
When I started doing Civil War reenactments in 1981 the first thing I learned was to make paper cartridges for my reproduction 1853 Enfield. Over time I experimented some and found a method that has worked well for me.
Posted by Pumpkinslinger on Friday, November 21, 2008 (16:26:10) (1890 reads)
comments? | | Score: 5
| PACT High Speed Digital Precision Powder Dispenser
|PACT High Speed Digital Precision Powder Dispenser
(Originally written in 2005)
Whenever I make up loads that will be near maximum pressure for hunting, or that require extra precision for matches or varmints, I like to weigh every powder charge. The spherical and flake powders generally meter very well, so all I need to do is throw the charge with my old RCBS powder measure and stick it on the scale to verify the weight. However, I never seemed to have much luck doing that with the extruded powders that I
Posted by Pumpkinslinger on Monday, May 12, 2008 (20:04:34) (4051 reads)
comments? | | Score: 4.5
| Is newer reloading information “wimpier” than the older stuff?
|Is newer reloading information “wimpier” than the older stuff?
Every so often when I am talking to folks about reloading I hear that the loads printed in current reloading manuals are much milder than the loads in older manuals. The most common reason given is legal liability, that the various companies have “wimped out” due to legal pressure. Since I had a variety of manuals on the shelf I decided to check some loads for myself to see if there really was that much difference. Also, if I found differences, I wanted to try to understand why there was a change.
The oldest bullet manufacturer’s manual on my shelf is a Speer #8, printed in 1970. I also have a Speer #14, printed in 2007. Obviously these would be a good place to start as they come from the same source and use the same bullets. I picked two very common cartridges to use for comparison, the .30-06 Springfield and the .45 ACP. The procedure was pretty simple. I just went through both manuals, found the loads using the same powder and bullet weight in each and wrote down the maximum recommended load. Then I determined the difference between old and new loads, both as grains of powder and as a percentage of the load. I did not list any muzzle velocities because different guns, with different barrel lengths, were used in the tests and I didn’t want to muddy the water with that variable.
I took the .30-06 first. I used three different bullet weights: 165 grain, 180 grain and 200 grain. I found five powders that were used with those bullets in both manuals. The results are in the table below.
Powder Bullet 1970 2007 Difference % Difference
H414 165 58.0 56.0 2.0 3%
H414 200 52.0 53.0 -1.0 -2%
IMR4064 165 51.0 50.5 0.5 1%
IMR4064 180 50.0 50.0 0.0 0%
IMR4831 180 59.0 59.0 0.0 0%
IMR4831 200 58.0 56.0 2.0 3%
IMR4350 180 56.0 56.0 0.0 0%
IMR4350 200 53.0 54.0 -1.0 -2%
IMR4895 180 50.0 47.0 3.0 6%
When you compare all the loads you see that the older ones averaged about 0.6 grains more powder, a difference of 1.1%.
Switching to the .45 ACP I picked two bullets, the 200 grain lead SWC and the 230 grain FMJ. I found five powders that were used in both manuals. The table below shows the results.
Powder Bullet 1970 2007 Difference % Difference
Red Dot 200 4.5 4.5 0.0 0%
Red Dot 230 5.5 5.3 0.2 4%
Bullseye 200 4.0 4.6 -0.6 -15%
Herco 200 6.2 6.0 0.2 3%
Unique 200 6.0 5.4 0.6 10%
Unique 230 7.0 6.5 0.5 7%
700-X 200 4.3 4.2 0.1 2%
700-X 230 5.0 5.1 -0.1 -2%
Again comparing all the loads the older ones averaged 0.1 grains more powder, a difference of 1.2%.
We can see that, while there is a small difference between the older and newer data, it’s not significant. There are a couple of things that can account for the changes. Different lots of the same powder will vary a little. You’ll note that sometimes the older charge weights are higher; sometimes the new ones are higher. I think another likely reason for any changes is that we now have better ways to measure the actual peak pressures. Electronics give us more accurate pressure readings than the “crusher” systems that were used before. To quote Alan Jones, editor of the Speer manuals #12, #13 and #14, “Sooner or later the old crusher system will be obsolete. We started the transition from crusher to electronic pressure measurement with the handgun cartridges in Number 12. Now we are converting the rifle data as time permits.” All Speer loads are kept at or below the standard industry maximum pressure.
It looks to me that the recommended loads today are no “wimpier” than the old loads. They should be safer, given the better pressure measuring equipment now available. One thing I would like to say is that these reloading companies have much better equipment than we do measure the pressures for the various cartridges. Personally I think it is foolish to try to exceed the maximum loads they have printed. I won’t risk the chance of damaging a gun, or me, to try to boost my velocities by a few feet per second. Let’s enjoy our hobby of reloading but keep it safe!
Posted by Pumpkinslinger on Friday, October 05, 2007 (04:06:41) (1615 reads)
comments? | | Score: 4
| Some Reloading Statistics
|Here are a few statistical numbers we arrive at when reloading and using a chronograph .. Most chronographs compute these figures for you , but they are nice to know how they are arrived at and what they mean .
For this example and to keep it brief we will use a 4 shot string instead of ten shots which gives you a much better set of numbers ..
Hv : the highest velocity recorded in the string
Lv : the lowest velocity recorded in the string
Es : Extreme Spread of the string
Av : Average velocity of the string fired
Sd : Standard Deviation , a measure of how close each shot will be to the average ...
Also I'm throwing in how to calculate ft lbs of energy and Taylor Knock Out Value , as well as number of loads per pound of powder
OK here we go with our 4 shot string
1. 2990 fps
2. 3010 fps
3. 2996 fps
4. 3004 fps
Hv = 3010
Lv = 2990
Es = 20 fps , the difference between the high and low velocities
Av = total of each velocity divided by the number of shots fired 2990+3010+2996+3004/4 or 3000fps Av
Sd is derived by multiplying the square root of the average velocity by the number of shots fired , and deduct it from the squares of all shot velocities -1 and then take the square root of this figure ..
Sd= 8.54 fps , or each shot will be within 8.54 fps of the average ..
FtLbs of energy is derived by the following :
velocity x velocity x bullet weight / 450240
For a 405 grain bullet at 2500 fps it will look like this
2500x2500x405/450240 = 5622 ft lbs
Taylor Knock Out Value is derived by the following formula :
bullet weight x velocity x diameter/7000
405 x 2500 x .458 / 7000
TKO of 66
Number of loads per pound of powder
There are 7000 grains in one pound of powder , so simply divide 7000 by the charge weight you are loading
Lets say you are loading 80 grains of powder in yur .17 souper mag ele slayer
7000/80 =87.5 loaded rounds per pound of powder ..
Posted by GroovyJack on Monday, July 23, 2007 (03:42:19) (4789 reads)
comments? | | Score: 4.16
| Forming AckleyImproved Brass
|Over the last thirty years or so building rifles and reloading, one subject that comes up frequently are the Ackley improved or more to the point ,what is the correct way to form brass. I'll get into some details and ramble on a bit, but I think in the end it will make sense.
( NOTE...I'm neither a writer or good picture taker. The old saying "A picture speaks a thousand words" applies .....)
The design is such that factory or handloaded ammo can be safely fired in an improved chamber. In reality,they are not ture wildcat cartridges. Wildcats are considered a rifle for which no factory loaded ammo exists. A 6.5-06 would be an example. The 6.5-308 was a wildcat for many years until Remington standardized it,now known as the 260 Remington. The 7mm-08 is another example. The term "improved" is a round reconfigured by fireforming,but where both ammo and chambered rifle exist.
With that, lets look at a typical AI cartridge. First, the shoulder is typically moved to a steeper angle, 40 degrees the most common, second, the body taper is reduced to a minimun spec,normally .010" case web to the shoulder and third, the neck-shoulder junction is moved back. This is a picture of a formed AI and parent cartridge, a 22-250 and 22-250AI.
The method to form AI brass is actually quite simple by firing factory or handloaded ammo,but I need to make a few comments first.
We all hear about the term "Headspace". A black art or a mythical process to some, but in my opinion, its simply a piece of brass trapped between two unmoveable pieces of steel. I believe in the K.I.S.S. principle.
Headspace is normally the distance from the boltface to a point on the case shoulder known at the "Datum" for a bottleneck rimless cartridge,however there are other ways to acheive it. As an example,when the 204 Ruger hit the market factory brass was at a premium, more costly than gold I think. One work around was to reform 222 Rem. Mag brass, the parent of the 204 R. Since I had a supply of left over 222 RM brass,by partically resizing the neck in the 204 die creating a "false" shoulder and fireforming, I made 204s. My load for the 204 is 29.5-BLC2 with a 32 grain bullet, the forming load,28.0-BLC2 and a 32. As to why that forming load I'll get to later. Take notice of the shoulder position between the 222 RM and 204 cases.
Another method of headspacing as used to form AI brass is the neck-shoulder junction. The design of a true improved places the junction back from that of the parent round. The reason for that is when a factory case is chambered the only contact is with the boltface and the junction. Remember, the AI chamber has a straighter body and steeper shoulder angle, so the casehead and shoulder-neck junction points are the only place a factory case will make full contact. As a side note, the orginal spec for the 30-06 was the same, casehead to neck-shoulder junction, not the datum!
Here are three examples, a 22-250AI,250-3000AI and a 270-308AI next to the parent cartridge. All three parent cases were randomally selected from lots of brass, right out of the bag except the 270,which was necked to 27 from 308 brass only.
Notice,in all three examples, the location of the neck-shoulder junction.
Here are the three parents,smoked to show where they headspace in the AI chamber. The bright ring indicates contacts the chamber wall or zero headspace.
Next, the parent, a chamber cast and a formed 250-3000AI case.
The pictures show the correct method for headspacing a factory parent to form improved brass. When the factory round is chambered there will be a slight crush fit if the chamber was cut correctly.
Now, if the chamber was cut correctly and is in fact a true AI, there are two way to make brass. One, simply fire factory loaded ammo of you choice, the other, handload forming rounds. Now, regardless of the opinions,thoughts,ideas and rumors what charge to use, the correct one is a stiff charge for the parent round. As an example, for my 22-250AI I shoot a load of 39.5 - Varget, the forming load is 36.0-Varget, both with a 50 grain bullets. That 36 grain load is just under the top for a 22-250 listed in the Sierra manual.
Although some suggest and get away with a reduced load to form brass, from expericence, I don't recommend it. A reduced load may casue "bouncing" effect and not fully form the case. (P.O. Ackley words) Although appearence wise it looks perfect, they can be as much as .030" short causing a casehead or top shoulder seperation. In my 30 some odd years using AIs I have seen this time after time. About a year ago, a showed me a case with a complete shoulder seperation from a 243AI. It happend on the second firing He had formed the using a light load for the 243 Win. Measurements of the formed brass showed they were .005 - .0015 short. I made a chamber cast to confirm the chamber dimensions, loaded a new batch of ammo and they formed exactly right. Lesson learned.
Another miscomception is a bullet jam. A bullet will not provide headspacing, it moves! Remember my defination of headspace, a brass case between two "unmoveable" pieces of steel? A bullet will begin moving before the case can expand 100%. I've heard of the firing moving the case forward when the primer is struck. If this happens,the case is too short, or the chamber is too long. I'll say it again, "a factory case will headspace on the neck-shoulder junction in a correctly chambered barrel".
I continue mentioning "correctly" chambered.. There are those that simply re-ream an existing chamber to convert to an AI without setting back the barrel. This creates a chamber longer than a true improved. Remember the AI is longer from the casehead to the top of the shoulder and shorter at the neck-shoulder junction than the parent round. For a 22-250 - 22-250AI the measurements are....
Casehead to shoulder ............ 1.514" ... 1.524"
Casehead to neck - shoulder .. 1.664" .... 1.644"
Overall length ....................... 1.912" .... 1.892
Top shoulder diameter ............ .414" ..... .454"
Using these measurements, you can see why setting back the barrel is required. If you thinking of having the conversion done,ask how the job will be done . If it doesn't include the setback, find another 'smith...quick! I made that mistake with my first one,a 280AI. Another gunsmith did the job over, correctly.
At times a reamer is cut to a special specs, ie..freebore,neck diameter,etc. Ask for the reamer specifications before having the job done. Its always a good idea to have the 'smith test fire the rifle and supply a few fired cases. The last few I've put together have been fully threaded and chambered Savage barrels. To headspace them, I use a factory unsized case. The 22-250AI and 250-3000AI in the pictures were done using factory brass and fireformed. In fact, all my Savages have be setup this way, AI or otherwise.
After forming, reloading for an AI is exactly the same as any other catridge and caution should be used in working up a loads as one would normally do.
Now, some may agree,disagree or have other opinions This is what I've been taught, do and have formed thousands of rounds without a problem.
Well, I hope this helps those thinking the AI route. They are not the problem some make them out to be. The benifits are a higher velocities and extended case life if loading is kept within reason, but one more step in the process of reloading.
Take care !
Posted by BillPa on Saturday, April 08, 2006 (16:27:17) (7496 reads)
comments? | | Score: 4.71
| Sectional Density - One Person's Ideas and Observations
One Person’s Observation
By: Robert Kaldahl
There are many facets of reloading that bear a direct relationship to the final product of your labor. Each decision made by the reloader had a direct bearing on the quality, usage and efficiency of the final round. This article is being written in an attempt to assist mainly those new to reloading and as a refresher for those that have been involved in reloading for a while.
We as reloaders manufacture our own ammunition for various reasons, it may be to save money, improve accuracy, enhance ballistics, and fill special needs (such as low recoil/velocity) and several other reasons. One that very seldom is mentioned is that of enjoyment in the sport.
Sectional Density is supposedly a factor in the Terminal Ballistics of any given load. SD is a factor that may have some determination into Penetration that is also determined by the resistance of the material hit. SD is also affected by the materials ability to resist penetration that results in energy dissipation and projectile deformation which affects the bullets stability and ability to penetrate a given medium. In our case this medium is the body of a game animal.
With all else being equal this article will deal with Sectional Density (SD). Many writers in the past and even a few this day and age have written charts and beliefs that certain SDs are good for specific categories of animals that we hunt. The general consensus is that the lower the SD the smaller and more fragile the game and the higher the SD the larger more robust the animal. This is not without its merits but leaves many factors omitted in a very complex decision. When a bullet’s SD is given the only thing that it is based on is a mathematical formula.
It is calculated with this formula:
Sectional Density =(Bullet wt. in grains)
7000 x ((bullet dia. In inches) x (bullet dia. In inches))
Let’s take a 30 caliber bullet weighing 165 gr.
165gr / 7000 x ((.308 x .308)) = 165 / 664.048 = .248
For the lay person, SD is a mathematical formula deriving a specific number that is generally used to equate that bullets ability to penetrate through a given medium. This formula is based on mass and the bullets cross-sectional area. But what does this number equate to? For many years I read and listened to others admiring the virtues of a bullet with a high SD. I thought that it had to actually mean something so for a long time I jumped right onto the same bandwagon. That is until one day on a hunt in Alaska for Caribou I was using what I just knew was a great bullet! To me this bullet was great! Big Green had made a beautiful 180 grain Spitzer Boat Tail that shot like a dream in a 300 H&H Magnum that I had picked up on a trade. It shot like greased lightening out to and past 300 yards flat as a road across North Dakota. It had a BC of .540 and an SD of .271, I thought this was just the ticket. Well so much for dreams, my first shot was at the grand distance of less than 50 yards, the bou was angling away so going for the off shoulder I let her rip. That great bullet hit the last rib on the left which shattered and the bullet tore a gash all along the left side of that bou! Well after two more shots it went down for the count. Upon skinning and dressing it out we found the majority of the jacket just under the skin in front of the left shoulder, no core was found anywhere from that shot, the other two shots were also found, again the cores had separated and blown apart. Talk about a mess, the only thing that was usable was from about the middle of the ribcage back, the front shoulders were a mass of bloody pulp. The two jackets were found in the on-side lung and most of the damage on the off side was from bone fragments and little pieces of lead. So much for a great SD of .271. Well I also happened to have 40 rounds of 150 grain Nosler Partitions with me so I thought I would at least try them. ( ** Note** This hunt was with a local Tribe in the Dillingham area so there was no limit as long as the game went into the Tribe’s Winter Food Cashe.). So now I go from a 180gr with an SD of .271 to a 150gr with an SD of .226, everything I had read told me that this bullet would be a failure on anything but very light skinned and light weight game. Needless to say, the 150gr Nosler Partitions dropped those bou like the hammer of Thor, not one bullet was recovered out of 8 that I shot, only one needed a second and that was my last one. All of them were shot in a migration and were all within 50 to 75 yards, these animals are not the most intelligent when in a migration, they may get a bit on the fast side but they don’t change their route by much.
When I returned home from this excursion I sat down and pondered what had happened. I came to the realization that SD and this formula does not take into account anything other than basic figures relating to a bullet, only its weight and diameter. This is a very general figure that really has no correlation into the bullets performance. It does not take into account the shape of the bullet, the materials the bullet is made from, the construction of the bullet nor the velocity that this bullet will traveling on contacting your intended target. Thus any bullet with the same weight and diameter will have the same Sectional Density.
This is a very flawed look at something that determines how effective your chosen bullet may perform. Using only a published SD to choose your bullet is like choosing your auto based only on the size of the engine.
Basing SD on weight/diameter neglects other considerations, jacket thickness, core density/alloy, mechanical/chemical bonding of the core & jacket, inclusion or absence of a mechanical partition, point configuration, inclusion of expansion enhancing tips or weakened areas of the jacket and or even the lack of a core such as in a homogonous bullet like the Barnes Triple Shock. There are even combinations such as the Combined Technologies Fail Safe that uses a homogonous forward section with a hollow point to assist expansion and a lead rear core with a steel back cup to keep the bullet from riveting.
One note that should also be remembered is that even a cast bullet in our example weight and caliber has the same SD as any of the manufactured bullets, no matter what the alloy used. Pure lead, 20:1, 30:1, Wheel Weights or even straight Linotype. What would happen if you were to launch a 180gr. pure lead bullet with a semi spitzer profile from your .300 Wiz Bang Magnum at 3300 fps at a 300plus pound Mule Deer at 50 yards. First off you would be lucky to hit it and second your bullet would miserably fail on contact with your target. So what good is SD in this case? Your bullet has an SD of .248 and according to general knowledge it falls in the area that is recommended for this size animal.
Now lets take this same weight bullet, change the nose profile to a metplat 80% of diameter flat point made out of a mixture of wheel weights and linotype. We then launch this bullet at a muzzle velocity of around 2100 fps from our .308 XYZ in a pistol configuration. We have a totally different result, more than likely venison in the freezer and a successful conclusion.
In the two examples above both bullets have the same SD, but one fails and the other provides complete penetration and the required wound cavity to be successful in taking our quarry. Note also that this is using cast bullets not anything fancy. Change the bullets to a 125 gr Nosler BT and our Magnum again fails due to performance of the bullet where our hunter with his pistol is again successful.
These are a couple of very exaggerated cases that make the point very clear, but how about the new reloader, what is available to them in determining what bullet would be best for their application. I don’t profess that I have all of the answers but hopefully this layman’s article will possibly assist at least one person.
Most hunters will go after some species of deer for most if not all of their “Big Game Hunting” so lets for ease and convenience use the common whitetail.
Whitetail deer from my best knowledge fall into the vicinity of 22 sub-species. The smallest is the Key Deer in the Florida Keys ( they may hit the scales at 25 – 30 pounds live weight for a huge deer) to the largest in the northern areas of the continental US and Canada that hit the scales at times well over 300 pounds live weight with some going over 375 pounds. As Key Deer are protected we won’t have to worry about them but just a bit further north in Florida whitetail abound. These too are small and it doesn’t take much to put them down but for all practical purposes you wouldn’t want to use the same bullet for them as you would going after a Michigan whitetail in the Upper Peninsula.
Lets use a .308 Winchester for our hunting firearm and only use it in a rifle. On our hunt in Florida what would we want to consider important for use in the selection of our projectile.
1) Size & Weight of our deer, probably on the order of a maximum of 160 pounds live weight.
2) Distance that the deer will shot at, lets use 250 yards as a maximum.
3) Incidental game that may be taken during the hunt. In this case there may be a good possibility that a good sized hog may appear.
Now lets see what is available in our local Gun Shop in the Reloading Section.
We have a huge selection of .308 bullets, they range from 100gr. to 220gr. The bullets available at this shop come from 6 different manufacturers and your reloading mentor suggested that you look at the 150 – 180gr weights. As you look over the boxes of the recommended weights you see that there are 11 different bullets just from Nosler on the shelf, 17 from Speer, 12 from Hornady, 10 from Barnes, 16 from Sierra & 8 from Combined Technology. Here is your list of bullets. Now you are really confused!
BARNES Bullets (10)
XLC Coated, .30 caliber 150 gr., Boattail
XLC Coated, .30 caliber 165 gr., Boattail
XLC Coated, .30 caliber 180 gr., Spitzer
X-Bullets, .30 caliber 150 gr., Spitzer
X-Bullets, .30 caliber 150 gr., Boattail
X-Bullets, .30-30 caliber 150 gr., FN
X-Bullets, .30 caliber 165 gr., Spitzer
X-Bullets, .30 caliber 165 gr., Boattail
X-Bullets, .30 caliber 180 gr., Spitzer
X-Bullets, .30 caliber 180 gr., Boattail
COMBINED TECHNOLOGY Bullets
Ballistic Silvertip .30 caliber 150 grain BT .308"
Partition Gold 30 caliber 150 grain Spitzer .308"
Fail Safe 30 caliber 150 grain HP .308"
Fail Safe 30 caliber 165 grain HP .308"
Ballistic Silvertip .30 caliber 168 grain BT .308"
Ballistic Silvertip .30 caliber 180 grain BT .308"
Partition Gold 30 caliber 180 grain Spitzer .308"
Fail Safe 30 caliber 180 grain HP .308"
HORNADY Bullets (12)
Hornady 30 Caliber 150 grain SP .308"
Hornady 30 Caliber 150 grain BTSP .308"
Hornady 30-30 Caliber 150 grain RN .308"
Hornady 30 Caliber 165 grain SP .308"
Hornady 30 Caliber 165 grain BTSP .308"
Hornady 30 Caliber 168 grain A-Max .308"
Hornady 30 Cal. 168 grain BTHP Moly Match .308"
Hornady 30 Caliber 170 grain FP .308"
Hornady 30 Caliber 178 grain A-Max .308"
Hornady 30 Caliber 180 grain SP .308"
Hornady 30 Caliber 180 grain BTSP .308"
Hornady 30 Caliber 180 grain RN .308"
NOSLER Bullets (11)
Partition .30 caliber 150 grain Spitzer .308"
BTH 30 caliber 150 grain Spitzer .308"
Custom Competition 30 caliber 155 grain HPBT .308”
Partition .30 caliber 165 grain Spitzer .308"
BTH 30 caliber 165 grain Spitzer .308"
Custom Competition 30 caliber 168 grain HPBT .308”
Partition 30 caliber 170 grain Round Nose 30-30 .308"
Partition 30 caliber 180 grain Spitzer .308"
Partition .30 caliber 180 grain Prot. Point .308"
Partition .30 caliber 180 grain Prot. Point .308"
BTH 30 caliber 180 grain Spitzer .308"
SIERRA Bullets (16)
Sierra 30 Caliber 30-30 150 grain FP .308"
Sierra 30 Caliber 150 grain FMJ BT .308"
Sierra 30 Caliber 150 grain Spitzer BT .308"
Sierra 30 Caliber 150 grain Spitzer .308"
Sierra 30 Caliber 150 grain RN .308"
Sierra 30 Caliber 150 grain HPBT .308"
Sierra 30 Caliber 155 grain HPBT .308"
Sierra 30 Caliber 165 grain HPBT .308"
Sierra 30 Caliber 165 grain Spitzer BT .308"
Sierra 30 Caliber 168 grain HPBT .308"
Sierra 30 Caliber 168 grain HPBT Moly .308"
Sierra 30 Caliber 175 grain HPBT .308"
Sierra 30 Caliber 180 grain HPBT .308"
Sierra 30 Caliber 180 grain Spitzer BT .308”
Sierra 30 Caliber 180 grain Spitzer .308"
Sierra 30 Caliber 180 grain RN .308"
SPEER Bullets (17)
308-150 GR. Flat Nose Soft Point 30-30
308-150 GR. Round Nose Soft Point
308-150 GR. Spitzer Soft Point
308-150 GR. Spitzer FMJ BT
308-150 GR. Spitzer Soft Point BT
308-150 GR. Mag-Tip Soft Point
308-150 GR. Grand Slam
308-165 GR. Spitzer Soft Point
308-165 GR. Spitzer Soft Point BT
308-165 GR. Grand Slam
308-168 GR. HP-Match BT
308-170 GR. Flat Nose Soft Point 30-30
308-180 GR. Round Nose Soft Point
308-180 GR. Spitzer Soft Point
308-180 GR. Spitzer Soft Point BT
308-180 GR. Mag-Tip Soft Point
308-180 GR. Grand Slam
We now have a total of 74 bullets to narrow down to one bullet that we are going to use for our whitetail and possible hog hunt. We know that all of the 150gr bullets have an SD of .226, the 165gr have an SD of .248, the 168gr have an SD of .253, the 170gr SD is .256 and the 180gr bullets max out at .271. What does this tell us. In a very short answer, the heavier the weight of a bullet in the same caliber the higher the SD, this in turn should give us more penetration of our bullet on an given animal. While this is generally very true we have to also look at a few variables. One such variable is somewhat easier to look at and that is the specific application that the manufacturer made a certain bullet for. In a 30 caliber bullet various manufacturers make 150gr & 170gr bullets for the 30-30. This cartridge is a fairly low velocity cartridge when compaired to a .308 Winchester using the same weight bullet. Being that it was designed for the velocity range of the 30-30 it was designed to expand and hold together at a maximum velocity of around 2300fps. If we use this bullet in our .308 at a velocity of 2700fps this bullet will in most cases come apart on impact unless the game is far enough away for the velocity to drop into it’s designed range. This being the case we take the bullets designed for the 30-30 off of our list.
This now brings our list down to 66. What else can we use to reduce the number of our available bullets to narrow our choice.
We will not use a bullet designed for Match or Competition as all manufacturers recommend that their match/competition bullets not be used for hunting game animals. I am not going to get into any arguments as to the successes that individuals have with them as these bullets “Are not designed for hunting game animals.” This equals 15 bullets on our list.
We now have only 51 bullets to choose from. Lets go and take off any round nose bullets as we would like to use a bullet that will be able to maintain it’s velocity as high as possible out to our 250 yard range.
That brings us down another 5 for a total left of 46 bullets on our list. What else can we use to bring it down a bit more. In your reading you have read that some of the bullets on your list are a very popular choice in the higher velocity 30 caliber cartridges such as the “Magnum” rounds and that those bullets were being used on much larger animals such as Elk, Moose, Caribou, Grizzly and Bison. Well we don’t need this heavily constructed bullet do we with the rifle we are using and the game we are after so lets take off those that we feel are for much larger game.
There is another 11 to take off bringing us down to only 35 bullets to make our selection from. Just for the sake of removing some bullets we decide that we want a bullet that has a Ballistic Coefficient of no less than .410 so that we can retain our velocity well out to our range of 250 yards.
Now we are down to 29 bullets, being that we are looking at the possibility of getting a wild hog in our sights we know that we would like to insure that we are using enough bullet even at a close range and we have read that some 150gr bullets may not provide the penetration that we would like so we decide to take off any that are 150gr.
Nine more bite the proverbial dust and we now have only 20 to make our selection from, what do we do now? Let’s take a hard look at what we are hunting, in many cases with reading and communicating with other hunters and what they use we have come to a fairly educated decision based on the cartridge that we are using and the game we are after we really don’t need the heavier weight of the 180 grain bullet so we will take them off of our list.
This leaves us with a selection of (11) - 165 & 168 grain bullets to choose from, this list is as follows:
XLC Coated, .30 caliber 165 gr., Boattail
X-Bullets, .30 caliber 165 gr., Spitzer
X-Bullets, .30 caliber 165 gr., Boattail
Ballistic Silvertip .30 caliber 168 grain BT .308"
Hornady 30 Caliber 165 grain SP .308"
Hornady 30 Caliber 165 grain BTSP .308"
Partition .30 caliber 165 grain Spitzer .308"
BTH 30 caliber 165 grain Spitzer .308"
Sierra 30 Caliber 165 grain Spitzer BT .308"
308-165 GR. Spitzer Soft Point
308-165 GR. Spitzer Soft Point BT
Our bullets weighing 165 grain have an SD of .248 and our lone 168 grain has an SD of .253, according to the charts this fall within the recommended range of Sectional Density for our game that we are hunting so what do we look at now. Given that we have looked at the reloading data for our cartridge we know that we will be able to load our bullet to a velocity of 2700fps. We know that the deer we are after is a light skinned animal and will not provide much ”Material Resistance” to our bullet but at the same time if we happen to get a shot at a hog the ”Material Resistance” will be much higher. Thus we need to know or make an informed decision as to which bullet we may decide to use. This is where the past results of others plays a large role, along with the re*****tion of the manufacturer. In most cases any of the above bullets will, with proper shot placement put venison and/or pork in your freezer, with your shot not being over 250 yards the difference in trajectory between a boat tail and a flat base bullet is so slight you would not realize the difference. Out of the above selection I will tell you this, the Barnes XLC and X-Bullet along with the Nosler Partition will without a doubt provide more penetration than any of the others. The Barnes bullets will expand the least of any of them also there have been cases of boat tail bullets loosing their core, on a deer this may not have any bearing on the final outcome but on a large hog it very well could. The last thing that you need to do is to shoot them to see which one meets your accuracy requirements.
With my past experience as well as that of many others I will give you my choices in the order of my preference.
1) Nosler 165 grain Partition – Very accurate Premium bullet in my rifle, taken hog, whitetail, caribou & black bear with this bullet with no bullet failures.
2) Combined Technologies Ballistic Silvertip 168 grain – hog & deer, sub MOA out to 300 yards with no bullet failures.
3) Barnes XLC Coated 165 grain Boat tail, not as accurate as the Nosler Partition but will out penetrate the Partition any day, probably due to the fact that it will not expand near to what the partition will.
4) Nosler 165 grain Ballistic Tip (Hunting) – As with the CT Ballistic Silvertip, Sub MOA and not a failure so far. Although I have read and heard reports that most of the Hunting BTs .308 and under may cause extreme tissue destruction at impact velocities over 2600 – 2700fps. I have roughly calculated that the highest impact velocity that I have reached was around 2550fps.
On the other hand, some of those that we took off our list would make very good bullets
for our hunt as they will penetrate in some cases even better than a standard 165 grain bullet. These are the 150 gr. Nosler Partition, the 150gr. Speer Grand Slams, the 150 gr. Failsafes and the 150 gr. Barnes variations. Hopefully you are not more confused at this point and you understand that there is more to a bullets ability to penetrate than it’s numerical Sectional Density.
In closing just think of this; You have a 500 pound hog that will stand still, will jump up alive after being dispatched to allow you to shoot it again and again with all of the bullets available to you with varying SDs, construction, shape, material, weight & caliber. How well will your bullet work at the following velocities. 100fps, 500fps, 1000fps, 1500fps, 2000fps, 2500fps, 3000fps, 3500fps & 4000fps. Plug in any velocity you wish, your hog is there for your testing and it doesn’t change. What bullet will you end up using? I’ll bet you won’t base your future selections based on Sectional Density any more!!!
Posted by Flint54 on Wednesday, March 29, 2006 (16:51:57) (10085 reads)
comments? | | Score: 3.75
| Burn rate Chart
|Here is a listing of the various burn-rates for current powders available for reloading.
1. Norma R-1
2. Vihta Vuori N310
3. Hodgdon Titewad
4. Accurate Nitro 100
5. Alliant Bullseye
6. Accurate Solo 1000
7. Scot Red Diamond
8. Alliant Red Dot
9. Alliant Promo
10. Hodgdon Titegroup
11. Accurate No. 2
12. Alliant American Select
13. Winchester AA Plus
14. Hodgdon Clays
15. Vihta Vuori N320
16. Ramshot Competition
17. Scot Royal D
18. Winchester WST
19. Hodgdon HP38
20. Winchester 452AA
21. Scot 453
22. Winchester 231
23. Ramshot Zip
24. IMR 700X
25. Alliant Green Dot
26. Hodgdon Int. Clays
27. Vihta Vuori N330
28. IMR PB
29. Accurate No. 5
30. Scot Pearl
31. Winchester 473AA
32. Hodgdon HS-5
33. Winchester WSL
34. Alliant Unique
35. Hodgdon Univ. Clays
36. Alliant Power Pistol
37. IMR SR-7625
38. Hodgdon HS-6
39. Ramshot Silhouette
40. Winchester WAP
41. Vihta Vuori N340
42. Winchester 540
43. Alliant Herco
44. Winchester WSF
45. IMR SR-4756
46. Scot Solo 1250
47. Vihta Vuori 3N37
48. IMR 800X
49. Accurate No. 7
50. Hodgdon Longshot
51. Scot Solo 1500
52. Ramshot True Blue
53. Vihta Vuori N350
54. Vihta Vuori 3N38
55. Hodgdon HS-7
56. Alliant Blue Dot
57. Winchester 571
58. Vihta Vuori N105
59. Accurate No. 9
60. Ramshot Enforcer
61. Scot 4100
62. Alliant Steel
63. Alliant 2400
64. Vihta Vuori N110
65. Hodgdon Lil Gun
66. Norma R123
67. Hodgdon H110
68. Winchester 296
69. IMR SR-4759
70. Vihta Vuori N120
71. IMR 4227
72. Accurate XMR 5744
73. Alliant 410
75. Vihta Vuori N130
76. Winchester 680
77. Norma N200
78. Accurate 1680
79. Vihta Vuori N133
80. Hodgdon H4198
81. IMR 4198
82. Scot Brig 4197
83. Accurate XMR 2015
84. Scot Brig 3032
85. Alliant RL7
86. IMR 3031
87. Hodgdon Benchmark
88. Norma N201
89. Scot Brig 322
90. Hodgdon H322
91. Ramshot X-Terminator
92. Accurate 2230
93. Winchester 748
94. Alliant RL10X
95. Hodgdon BLC-2
96. Accurate 2460
97. Hodgdon H335
98. Ramshot TAC
99. Hodgdon H4895
100. Accurate XMR 2495
101. Alliant RL12
102. IMR 4895
103. Scot Brig 4065
104. Vihta Vuori N135
105. Hodgdon Varget
106. IMR 4064
107. Accurate XMR 4064
108. Accurate 2520
109. IMR 4320
110. Norma N203
111. Vihta Vuori N140
112. Vihta Vuori N540
113. Accurate 2700
114. Ramshot Big Game
115. Alliant RL15
116. Hodgdon H380
117. Winchester 760
118. Scot Brig 4351
119. Hodgdon H414
120. Vihta Vuori N150
121. Vihta Vuori N550
122. Accurate XMR 4350
123. IMR 4350
124. Hodgdon H4350
125. Norma N204
126. Ramshot Hunter
127. Alliant RL19
128. Vihta Vuori N160
129. Vihta Vuori N560
130. IMR 4831
131. Scot Brig 4831
132. Norma N205
133. Accurate XMR 3100
134. Winchester WMR
135. Hodgdon H4831
136. Norma MRP
137. Alliant RL22
138. Winchester 785
139. Hodgdon H450
140. Accurate Mag Pro
141. Vihta Vuori N165
142. Winchester WXR
143. IMR 7828
144. Accurate 8700
145. Hodgdon H1000
146. Ramshot Magnum
147. Alliant RL25
148. Hodgdon Retumbo
149. Hodgdon H870
150. Vihta Vuori N170
151. Vihta Vuori 24N41
152. Hogdon 50 BMG
153. Vihta Vuori 20N29
Posted by DallanC on Monday, January 16, 2006 (22:25:18) (6743 reads)
comments? | | Score: 4.5
| High Pressure!
|Hi Hunters, a cautionary tale. I live and hunt here in England and have reloaded for my 25-06 and now 6.5-06 for the last ten years. The rifle is a Sako TRG-S action which now has a Krieger stainless 26 inch barrel chambered 6.5-06. My sporting rifle has never had commercial ammunition through it, even when it was a 25-06; (I had it re-barrelled as a 6.5 two years ago). I chose 6.5-06 for the available bullet selection.
Hunting in England for small deer I could use a 120 grain Sierra, for instance, and in Scotland I use the 140 grain Game King for the much larger Red Deer. I have also used Speer, Nosler and Hornady bullets very successfully. Seeking to reduce the powder load for use on the smaller species, (we have Roe, Muntjac and Chinese Water deer), I reduced my powder load, Viht N160, down to 45 grains and filled the rest of the case to the base of the neck with coarse semolina. I have a photo which shows the result on the first shot, with a normal case for comparison. The bolt had to be hammered open!
I am grateful for the strength of a Sako three lug action and very embarrassed by the incident, as I must have loaded several thousand rounds, target and hunting, with no problems. The photo shows major brass flow into the extractor slot, a popped primer and a distorted primer pocket. When I have worked out how, I will send the photo. The ridiculous thing is that 45 or 46 grains of Viht N160 drives a Sierra 120 grain soft point very accurately at about 2700 fps, a sensible load by any standards. Moral:- Don't mess with something that works!
Best wishes to all for 2006,
Posted by moritz on Wednesday, January 04, 2006 (20:18:09) (6572 reads)
comments? | | Score: 2.4
| Adjusting Powder Measure
|Ya know how aggravating it is to try and set your powder thrower for a particular charge weight ?? Ya turn screw in , throw a charge , weigh it , turn screw out , throw a charge , weigh it ..
Yeah I can see you've been there ..
Well here is a shortcut I recently "discovered" . I am sure that I am not the first ...
Turn the adjustment screw for the charger out a good bit ..
Take your scale and weigh the charge that you want to throw ..
Dump the weighed charge into the empty powder dispenser .
Now turn the handle about halfways between the load and dump positions , so the powder charger is against the wall of the funnel . Turn the adjustment screw in until you feel firm pressure . With a little practice you'll get within a few tenths of the desired weight .
Took me over thirty years to figure this one out ..
Hope it helps ..
Posted by GroovyJack on Sunday, May 29, 2005 (18:21:44) (6306 reads)
comments? | | Score: 4.71
| OCW ( Optimal Charge Weight )
|:D I would like to give all credit for the following information to
" Dan Newberry " this article was posted by him on the
( www.savageshooters.com ) website along with links to his website at (www.clik.to/optimalchargeweight )
This information is something that I wish that had been available years ago, it would have saved me tons on powder, primers & bullets finding a good load for all of my rifles. Give it a look over, I hopw that you get as much from it as I have. Best Wishes & Safe Shooting. Flint54
Do you have a need for a decent long range rifle load? It really doesn't require as much work as one might suppose--in fact, you can actually develop and be shooting the load for your rifle in as little as 30 shots or so. Don't believe it? Read on...
Most of us get tripped up by loading WAY too many shells of each powder graduation. We decide to try too many bullet types, and often too many powders. All the while, you're spending money on this end that could be saved to purchase more of the right bullets and the right powder after you've identified the final load which you will be using.
Here's the shortcut to putting together an accurate and successful load for your LR rifle.
Choose a bullet. That sounds easy, but it's getting harder and harder all the time. There are many--almost too many--choices out there. My recommendation would be to take a look at what the successful shooters in the long range competitions are using, and narrow your choices down that way. As a rule, you'll *****t to go with the highest BC (ballistic coefficient) that your rifle's twist will stabilize. Of course if you're shooting a chambering that won't get the required velocity from a very high BC bullet, you may *****t to step down a bit in bullet weight so you can step up in velocity. Again, see what folks who "know what they're doing" are shooting and that'll get you some good ideas.
We've all heard folks say (and have perhaps said it ourselves) that "my rifle doesn't 'like' Varget, IMR 4895, BL-C(2)," or whatever. Keeping in mind that this is an opinion, allow me to say that I'm not inclined to believe that a particular rifle really dislikes a particular powder. Barrels aren't all that different. Likely, when we came to the conclusion that our rifle didn't "like" IMR 4064 (and folks, I remember concluding that once, way back when ) we were shooting with a bad scope, bad bullets, incorrect powder charge range, bad powder or bullet lot, poor or underdeveloped bench technique--or any number of other things. I've since proven that that old rifle which I thought hated IMR 4064 actually likes it after all. And it likes it very, very much...
I mention the above because powder choice is very important when you set out to develop a load. And the overwhelming liklihood is that your barrel will indeed "like" a standard powder used by many other shooters using the same chambering.
So, let's say you're working with a Remington 700 in .308, and you *****t to ring the 1K gongs. That rifle will have a 1:12 twist, and it'll handle bullets up to 180 grains pretty easily. Maybe a little heavier--but let's keep them at 180 and under so we can get plenty of speed from them. Let's say that after reviewing all of your options, you've decided to stay pretty standard and go with the Sierra 175 grain Matchking. (good choice, by the way). Now all you've got to decide is what to push it with.
If you'll poll most .308 win long range shooters, you're going to find these powders rule: (in no particular order) IMR 4064, IMR 4895, Varget, H4895, BL-C(2), Reloder 15, and the old stand-by W748. Wow. Which to choose...
Here's the truth. You can put together a pretty decent long range load with any of those powders. The idea that your barrel won't "like" one of those is extremely remote--again, my studied opinion. You can make any good powder in the proper burn range work for you.
So you've chosen a powder. For the sake of discussion, let's say that your buddy gave you a good deal on a couple pounds of W748 he had left over from an eight pound jug.
Next you gotta have some brass. Again, check around. You're going to be told that Lake City Match, Lapua, Winchester, Norma, and IMI are some of the better choices. Since Lake City isn't always available and Norma is too expensive for what you get, that leaves Lapua, Winchester, and IMI. IMI is a military brass case, and in the match form it's quite good. It's on the heavy side, so reduce listed maximums accordingly. Lapua is great brass, and can be had at a decent price. I like Winchester because it's cheap and good. Lapua is a little more than twice the price of Winchester, but it is better brass as far as uniformity and case life goes. But since I've shot some of the best groups of my shooting career with Winchester cases, and since you asked me you've bought a couple hundred Winchester brass cases.
Do I need to de-burr the flash holes and uniform the primer pockets? In my opinion (in this opinion piece, remember?) you shouldn't bother. I've not seen any compelling evidence that match prepping cases really helps practical accuracy at all (except in the instances where a shooter is working with a non-optimal powder charge--which of course he shouldn't be -- see "walking the tightrope to accuracy" referenced later in this post). John Barsness used a Remington 40X with a custom barrel a few years ago to test the benefits of 1000 shots of prepped .223 brass versus 1000 shots of unprepped, straight from the bag Winchester brass. Guess what? The average group size favored the unprepped brass by a slim margin! So don't waste your time.
Gotta have primers, right? Right. And here again, don't lose sleep over which primer to use. Some powders do indeed seem to have a "favorite" primer, likely because of how hard (or easy) they are to light uniformly. Since you went with W748 I think I'd stick with the Winchester primers. W748 is a ball powder, and it will pack into the flash hole inside the case (and possibly even find its way into the primer cup). WLR primers are on the hot side, and will breath good fire right on through if you end up with some rounds with impacted flash holes and others with unobstructed flash holes. Ball powder really isn't harder to light than extruded (stick) powder--but over the years knowledgeable folks have come to believe that ball powder shows an affinity for hotter primers. (Speer actually uses magnum primers with W748 and other ball powders). I wouldn't go that far, but I do think WLR's are great with the W748.
But you couldn't find WLR's. Sold out. Losing sleep...
Get the Federal 210's and let's get some stuff loaded up.
You're going to be pushing a 175 grain bullet with the W748. Let's see... what do the loading manuals say? An average of three sources I looked at says that 45.0 grains is max with 180 grain bullets. Why did I look at the 180's? Because I couldn't find (and you likely won't either) much data for W748 and the 175 grain Sierra Matchkings.
For an OAL you will begin at about a caliber's depth of bullet into the case. Don't count the boattail, by the way--you *****t a caliber's depth of bearing surface for good neck tension. For a thirty caliber bullet, that'll of course be about .30" or so. You can "depth tune" the finished product later on, by testing seating depth changes in .005" increments. Generally, a properly developed OCW load will not be really particular about the seating depth--but you can "fine tune" the accuracy by slight seating depth changes if you wish. An aside: If you find that a caliber's depth of bullet bearing surface still leaves the cartridge too long to magazine feed, just seat the bullet to near the max length the magazine will tolerate. This is a Remington 700 we're talking about here so just go on ahead and seat the bullet to an OAL of 2.810", tip to case head. That way it should mag feed easily...
Using the OCW instructions you'll find at my website ( www.clik.to/optimalchargeweight ) you put together ONE cartridge using 41.5 grains of W748, then another with 42.0 grains, and a third with 42.5 grains, and a fourth with 43.0 grains. These are the pressure test shots. Now you're ready to load three each of the following charges: 43.4 grains, 43.8 grains, 44.2 grains, 44.6 grains, and finally 45.0 grains. You're moving up in approximate 1% increments.
(An aside: If reliable sources indicate that you can go slightly above 45.0 grains with the W748, then go ahead and load three cartridges with 45.4 grains. Fire these in the round robin test mentioned next if and only if there are no pressure signs at the 45.0 grain level. In the event that 45.0 grains would be the OCW, you'll need the 45.4 grain charge to prove that. For the purposes of this discussion, we'll stick with the five graduations already mentioned).
You fire the three test shots in increasing charge weight order to check for pressure signs, and set your zero as close as possible to the bullseye at 100 yards with shot number 3. Now, you'll have five targets set up at 100 yards. Keep the bullseyes as close to each other as practical to minimize light and angle differences between them. I just put five squares on the same white piece of paper, about three to four inches from each other.
Beginning with the 43.4 grain charge, fire one shot at target 1. Then go to the 43.8 grain charge and fire one shot of that at target two, move to target three, and fire one shot of the 44.2 grain charge at that target, and so on. Go through all five targets three times each in this "round robin" fashion. Watch for pressure signs along the way, and stop if you encounter such. When you're done with all fifteen test shots, you'll have a three shot group of each charge weight represented on its own target.
(A tip: For your individual targets, use 5 x 7 index cards with black squares drawn in the center with a Sharpie marker, each square in the identical location on each card. Use one card for each target. That way, when you're done, you can see which powder charge graduations hit the same POI by stacking the cards).
Now you're almost done. Look at the groups and determine which three groups all appear to be hitting the same point of impact on the 100 yard target spots. Let's say that 44.2, 44.6, and 45.0 grains all seem to hit in the 2 o'clock area, about an inch from center of the bull. Since all three of these groups hit the same spot (for the most part) then your choice for your long range load is going to be 44.6 grains.
At this time you've fired eighteen times, and spent eighteen bullets, eighteen charges of powder, eighteen primers, and you've diminished your barrel life by only eighteen rounds.
Yeah, but who's gonna really believe that 44.6 grains of W748 (in this example, remember) is going to shoot tight at long range? Folks, in all of the OCW tests I've done I've yet to find a recipe developed in this manner which wouldn't shoot well "way out there." You see, by virtue of the fact that you've chosen a powder charge weight from the center of a three shot string of graduations which impact the 100 yards target in the same location--you're choosing a pressure tolerant load, in the "sweet spot," if you will.
But let's shoot three bracket groups to be sure that 44.6 grains is indeed the Optimal Charge Weight. (Remember, this is an example--I'm not contending that 44.6 grains of W748 is an OCW load). For your bracket groups, you'll simply shoot one shot of 44.2, one of 44.6, and a third of 45.0 grains into the SAME GROUP at 100 to 300 yards (the longer the better here, but since some folks don't have immediate access to ranges longer than 100 yards that range would be fine). All three shots--even though they are of three different charge weights, should print together on the target. By "together" I'm speaking of MOA from rifles capable of such. Here is an example of an OCW bracket group fired for the .243 win at 100 yards:
If you shoot three bracket groups you've now shot a total of only 27 rounds. And if those groups land tight at 200 to 300 yards, you know you're in the OCW zone, and you can be all but certain that the 44.6 grain charge will perform very well for you at longer ranges.
So at this point, with less than 30 rounds invested, you very likely have a load recipe that's going to serve you well at the longer ranges.
What about velocity?
Notice, however, that I didn't mention anything about a chronograph just yet. For my part I don't get curious about the velocity of a load until I find an accurate load. Many folks "shoot for" a particular velocity when developing a load, but the truth is if you *****t a pressure tolerant load (or by definition an Optimal Charge Weight load) you cannot let the chronograph tell you where to take the recipe. There will normally be two distinct OCW zones with any given powder and bullet. The low zone is fine for close work, but it'll generally have a larger extreme spread (velicity differences from slowest to fastest shot) than the high node OCW will. And for a long range load, you'll *****t as much velocity as you can safely get. Generally, the OCW will exhibit tight velocity spreads from the get go, but you shouldn't simply shoot a bunch of shots across a chronograph and look for a tight velocity spread--that can lead you astray because some non-optimal powder charges may indeed show tight numbers so long as you're within .1 to .2 grains or so. That's not good enough, as you'll be "walking the tight rope to accuracy," and having to do meticulous case prep, weigh powder charges to the tenth of a grain, weigh cases and such--just to stay on that tight rope. Step slightly to either side and accuracy "falls off" noticeably.
So by shooting the round robin sequence through the higher charge levels (right up to the maximum) you will almost certainly find the high OCW zone. Once you've identifed the high OCW zone (by finding the three consecutive groups which have a common POI) you choose the center charge weight, and live with that velocity. If possible, you should chronograph the final product (44.6 grains of powder in this example) so that you'll have a rough idea of trajectory, and also the velocity at 1000 yards. You could shoot several strings across the chronograph just to see what the ES would be, but why not just shoot the recipe at long range and see what the vertical spread looks like? The target is the final arbiter anyway--regardless of what the chronograph says or doesn't say.
A 2600 fps 175 grain (30 cal) Sierra Matchking with it's ~.500 BC will make it very nicely to 1000 yards. And with a 24 to 26 inch barrel, you should have no trouble getting close to or a little above 2600 fps from the 175's with the high OCW of W748.
A final note: Could I have used IMR 4064 or another type of primer and gotten an even tighter shooting load? Very possibly, yes. Perhaps not. But the degree to which a load is more or less accurate is far less important than simply learning all about the load you have. A 3/4 MOA load made with W748 and Federal primers, and practiced with religiously is a far more formidable system than a 1/4 MOA load in the hands of a "fair weather shooter" would ever be.
Don't develop "a" load. Develop the load. www.clik.to/optimalchargeweight
Posted by Flint54 on Friday, May 13, 2005 (14:54:30) (13842 reads)
comments? | | Score: 4.87
| How do I "tune" a load to be more accurate?
|Each rifle is different and will usually like a specific load “recipe” to achieve best performance. There are several things which can be done to enhance accuracy of a load for a specific rifle. The following are tips in no particular order.
#1) Try altering the amount of powder used in the load. Move up from the minimum recommended load in your reloading manual in .5 grain increments until you either notice excess pressure signs OR you reach the maximum recommended load, which ever comes first.
#2) Try changing powders to a type of powder which will fill the case more. Most rifles like powder charges which fill the case 80% or more.
#3) Try adjusting the seating depth of the bullet. Most rifles will like the bullet a few thousands of an inch off the lands. This usually requires a Cartridge headspace gauge to measure but can be done by denting an empty, sized case mouth slightly and lightly inserting a bullet. Chamber the empty case slowly, letting the bolt act as a press and the rifling to seat the bullet into the case. Take an Gage OAL measurement of this case length and seat the bullet a few thousands more. Barnes X bullets usually like more freebore to the lands so try seating them deeper. *Note: when altering the seating depth of a cartridge, reduce the load slightly as the volume within the case is also altered as the bullet is seated at different depths.
#4) Get a primer pocket uniformer tool and make sure your primer pockets are uniform. When most brass is created, a small burr is left inside the case and can make for a non-uniform burn of the powder.
#5) Try different brands of bullets and even bullet weights. Some rifles are picky as to what weight of bullet they will shoot well. This can depend on the twist of the barrel rifling.
Posted by DallanC on Tuesday, May 10, 2005 (23:48:13) (12001 reads)
comments? | | Score: 3.95
| Terms and Definitions
|Reloading: The process of sizing, charging and assembling a firearm cartridge.
Reloading Manual: A manual produced by powder and componant manufacturers listing detailed data and steps to reload cartridges. Most manuals contain ballistics and energy tables as well.
Cartridge: A cylindrical, usually metal casing containing the primer and charge of ammunition for firearms.
Case: A brass container to contain ignition source, propellent and projectile into a single object for a firearm.
Bullet: A projectile which is fired out of a firearm.
Primer: An ignition source for a cartridge which explodes when struck by firearms firing pin, thus igniting the cartridges powder.
Powder: A propellent which when burned, produces extreem pressure to force a projectile down the barrel of a firearm.
Press: A device used to assemble firearm cartridges.
Reloading Die: A precision form the size of a rifle cartridge into which a case is forced thereby transfering the image of the die to the case.
Powder Scale: A precision scale used to accurately weigh powder by grains.
Powder Measure: A precision measure used to accurately measure amounts of powder.
Powder Trickler: A tool which trickles a slow amount of powder. Used to add fine amounts of powder to a scale.
Chamber: The area at the rear of a rifle barrel into which a rifle cartrige is placed.
Boltface: The face of the bolt into which the base of a case is placed. Contains a hole through which the firing pin is able to strike the primer.
OAL: Over All Length. Refers to the total length of a cartridge.
COAL: Same as OAL, stands for Cartridge Over All Length.
Gage OAL: A length, measured from the base of a cartrige to a point on the bullet of a specific diameter. Requires a specific tool.
Headspace: The volume left between the top of a cartridge shoulder or rim, and the chamber after closing the firearms bolt.
Freebore: The distance between the olgive of a bullet and the start of the barrels riflings.
Riflings: The grooves which twist down the inside of a barrel. Riflings are what gives a bullet it's spin.
Lands: The raised portion of a grooved surface.
Fields: The recessed portion of a grooved surface.
Rim: A recessed groove at the base of a case.
Belt/Belted Case: A circular protrusion at the base of a case to limit how far a case will enter a firearms chamber.
Primer Pocket: A recessed area in the bottom of a case into which the primer is placed.
FlashHole: A hole in the bottom of a case through which flame from the primer enters the case and ignites the powder.
Case Neck: The top of a case which holds the bullet in place.
Chamfer: To cut off the edge or corner of a case (bevel).
Case Lube: A special lubricant which aids the cases re-sizing process and to not get stuck in the die.
WildCat: A special Caliber for a firearm which is not available by a commercial manufacturer. Many reloaders create new and unique calibers and many current factory calibers originally started off as wildcat calibers.
Posted by DallanC on Tuesday, May 10, 2005 (23:48:02) (2112 reads)
comments? | | Score: 4
| What are the steps to reload?
|A common question which seems to arise frequently is “how do I reload”. Reloading rifle, pistol and shotgun cartridges is a fairly simple and safe process. Below are the steps to reload rifle cartridges. New reloader’s should purchase a reloading manual and read its steps to be more familiar with the process. A quality reloading manual is an absolute requirement.
(Pictures are coming very soon)
Step 1). Begin with a close inspection of the empty cases. Inspect the neck area and shoulder, looking for any cracks or signs that the case may be failing. On belted magnum cases, inspect the webbing just above the belt for potential separation. Inspect the primer area and look for signs of worn primer pockets, usually black sooty edges where the primer contacts the case. Minor dents and blemishes are ok but sharp creases in the case from dents etc are unrepairable. Discard any questionable cases.
Step 2). Clean the cases by using a tumbler or vibrating case cleaner. Brass polishing compounds are not recommended due to Ammonia which will weaken the case.
Step 3). Cases must be lubricated prior to resizing or they may become stuck within the reloading dies. Apply a thin coating of Case Lubricant to the case walls. Avoid lubricant on the case shoulder as this can case shoulder collapse when the case is resized. Lightly lubricate the inside of the case mouth with a case neck brush.
Step 4). Lower your presses handle thereby raising the ram to its highest position. Select the resizing and primer decapping Die for your rifle caliber. Screw it into your press until it contacts the presses ram. Return your presses handle to its upright position and tighten the resizing die another ¾ to 1 turns (consult your dies instructions if available for correct installation of the die). Tighten the dies lock-ring.
Step 5). Place the base of the case into the shellholder at the bottom of the ram. Apply pressure on the handle forcing the case up into the sizing die. Note the primer which is pushed out the bottom of the case. Apply pressure to return the press handle to it’s up position. The down stroke of the presses handle will force the case up into the die, changing it’s size and removing the primer. The up stroke of the presses handle will resize the case neck and mouth. It shouldn’t be too difficult to resize a case, if so there might not be enough lubricant on the case.
Step 6). Resizing of cases will cause the case length to grow. Using a set of calipers, measure the length of the resized cases. Use a case trimmer to return any cases which are too long to their original length. This length is available out of your reloading manual. Calipers are also reasonably cheap, I recently bought some locally for $14 so it’s something no-one should be without. Remove the die from the press when you are finished resizing your cases.
Step 7). Using a case-neck deburring tool, remove the burrs from both the outside and inside of the case mouth. This only needs to be done once after case trimming and not again unless the case has been trimmed. Also, you are only trying to remove the sharp edge of the case to aid in bullet seating so if your case feels “sharp” then you have removed too much material. Use a light touch.
Step 8). Apply the new primer. Follow your presses manual to install new primers or, if you have a hand priming tool, follow it’s instructions to install new primers. Be very careful to use dry, oil free hands when handling primers as any oil or case lube can render them inert.
Step 9). Consult your reloading manual to determine the correct amount and type of powder for your rifles caliber and bullet weight and type. Check and double check you are using the correct components as listed in the manual (example: H4831 is not the same as IMR4831 even though the numbers are the same). Using a quality, accurate measuring scale, measure out the amount specified for the load. Pour this into an empty, primed case and set it aside. Repeat for all your empty cases, placing charged cases in another location from empty cases to avoid confusion and accidental “double charging” of a case.
Step 10). Install your bullet seating die the same as in step 4 with one exception. Place an empty case into the shell holder and screw the die down until you feel it contact the case. Back off ¼ of a turn from this contact point to avoid crimping the case (note: if you desire a case crimp, follow the Die’s instructions, or your reloading manual for setup). Tighten the lock-ring for the die. Back off the Dies seating adjustment screw several turns.
Return the press handle to it’s up position and place a bullet over the mouth of the charged case in the die (hold the bullet with your hand to avoid it falling). Slowly lower the press handle until the handle is at it’s lowest position. Note: Stop if you feel the bullet contact the dies seating unit.
Step 11). Now we need to adjust the actual seating depth of the bullet into the case. We start off by having the adjustment screw backed off enough that it doesn’t contact the bullet on the down stroke of the press handle. We do this so we can increase the depth a little at a time until we achieve the correct depth.
The presses ram should now be in the down position and the case and bullet not contacting the die itself. Screw down the seating adjustment screw until you feel it contact the bullet. Raise the presses handle partially and screw down the seating adjustment 1 turn. Lower the handle and you should feel the bullet being pressed into the case. Remove the case and compare the length of the cartridge with the OAL (over all length) as specified in your reloading manual. If it’s too long, place the case back onto the ram and tighten down the seating adjustment another turn, repress and remeasure. When you have achieved the correct length as specified in the reloading manual, set the lock-ring for the seating adjustment screw. Press in bullets for all remaining charged cases.
**Note: A quick shortcut for beginners to achieve proper seating depth is to place a previously loaded “Factory” cartridge onto the ram, and adjust the seating depth until it contacts the “factory” bullet. Make sure that if you use this method, the factory round uses the same bullet type and weight as the ones you are reloading. Press a bullet into a charged case and double check the OAL.
Step 12). Wipe off all excess lubricant from the case.
Step 13). This is a very important point. WRITE DOWN ALL INFORMATION REGUARDING THE LOADS YOU JUST CREATED! Information such as Date, bullet type, bullet weight, powder type and amount, primer type, number of times the cases have been reloaded, seating depth etc etc are VERY useful down the road. I recommend buying a cheap pack of stickers, which can then be slapped on the outside of the ammo box. If you *****t a more professional look, Midway sells rolls of reload information stickers which are simple to fill out.
Step 14). We are all done! Clean up the reloading bench and head for the range! Go shoot and have fun!
Posted by DallanC on Tuesday, May 10, 2005 (23:47:49) (8678 reads)
comments? | | Score: 4.66
| What equiptment do I need to reload?
|The basic equiptment needed to begin reloading is as follows: An up to date reloading manual, reloading press, reloading dies, powder scale, case mouth chamfering tool, case neck brush and case lube. Additional but not required equiptment may include: powder measure, powder trickler, case tumbler, primer pocket uniformer, flashhole de-burrer, case neck uniformer, cartridge comparator, calipers etc.
Posted by DallanC on Tuesday, May 10, 2005 (23:47:37) (1391 reads)
comments? | | Score: 0
| What is the best way to get started reloading?
|The simplest way to get started reloading is to purchase a beginners kit which is offered by nearly every single reloading equiptment manufacturer.
RCBS offers a "Partner" reloading kit for around $125 which includes everything to get started as well a "Rockchucker" reloading kit which offers upgraded equiptment to the partner kit. Midway offers a terrific deal with light and heavy duty equiptment. Shop around to get an idea of what will satisfy your needs.
Posted by DallanC on Tuesday, May 10, 2005 (23:47:25) (7954 reads)
comments? | | Score: 4