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#1: Hornady OAL Gauge and Comparator Author: MacD, Location: Canada

Posted: Tue Jun 26, 2012 2:10 pm
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So I put down $100 for the straight OAL gauge and the comparator kit. The kit comes with 5 bushings of the popular bullet sizes from .224 up to .308. I got out my .223 Remington and 3 sample bullets. 50 G V-Max, 50 G Varmint Grenade and 40 G Ballistic Tip. Readings with the OAL were within .001 and .010 0f my readings with my homemade OAL gauge. I like the comparator. I believe that the LEE seating die engages the ogive to seat the bullet. I hope this means better consistency in seating depths. I currently measure 1 in 4 rounds for OAL and find some slight variances. When I measured 10 bullets of one type I found a +- .001 variance in their length. This could be my calipers but it also could be normal manufacturing tolerances. Since what really matters is where the ogive diameter is equal to the start of the lands setting up using ogive hopefully will make a difference. One note was the short 40 G ballistic tip would have only maybe 1/16" above the boat tail in the case mouth if I tried to load it to the lands. Obviously to have it held securely I have to allow substantial jump. This is also my least accurate bullet but it could be the rifle's 1 in 9 twist that is mostly responsible for this.

#2: Re: Hornady OAL Gauge and Comparator Author: PaulS, Location: South-Eastern Washington - the State

Posted: Tue Jun 26, 2012 3:24 pm
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MacD,
Just because a bullet jumps to the rifling doesn't mean that it will not be accurate. My A303 has a very long chamber lead (You cannot seat a 180 grain bullet to the lands) but it shoots everything from 110 gr to 200 grain bullets to less than 1MOA consistantly. Most of my aggregate groups are within .75" from center to center after load work-up.
It has a lot to do with consistancy in the loading process but it also has a lot to do with the barrel. It is an as-issued barrel but it is a good one. It is free-floated, has a Timnet 4 pound "hunting" trigger and I only neck size the brass and shoot loads that are below max by an average of 3%. My gun likes it but each one is different.

#3: Re: Hornady OAL Gauge and Comparator Author: Ominivision1, Location: Iowa

Posted: Tue Jun 26, 2012 10:03 pm
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I agree with Paul, my 340 Weatherby which are known for their generous "free bore" is a tack driver, and I also have an M700 30/06 that shoots MOA at 200 yards when bullet is seated .022" from the lands and with the same exact load in another M700 gives poor results using the exact same distance from the lands.

My conclusion: Each rifle, handgun is it's own individual. And that what makes reloading fun. Searching for the "Holy Grail" load for your particular firearm.

#4: Re: Hornady OAL Gauge and Comparator Author: Eremius, Location: Owosso, MI

Posted: Wed Jun 27, 2012 7:15 am
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PaulS wrote:

MacD,
Just because a bullet jumps to the rifling doesn't mean that it will not be accurate. My A303 has a very long chamber lead (You cannot seat a 180 grain bullet to the lands) but it shoots everything from 110 gr to 200 grain bullets to less than 1MOA consistantly. Most of my aggregate groups are within .75" from center to center after load work-up.

I've actually been playing with seating depth on my Rem700 .22-250. After initial testing, it seems to like some free bore. I want to run some additional tests but it really surprised me.

#5: Re: Hornady OAL Gauge and Comparator Author: fnuser, Location: S.W. Missouri, U.S.A.

Posted: Wed Jun 27, 2012 9:22 am
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Yeah I used to think you had to "cram it in straight" now I wonder if it don't hurt to "let it glide in natural".

#6: Re: Hornady OAL Gauge and Comparator Author: MacD, Location: Canada

Posted: Wed Jun 27, 2012 2:09 pm
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When I worked up a load for the Barnes Varmint Grenades I found that just off the lands was best. They are a copper filled bullet and are longer than other 50 G bullets. This experimenting is what makes rolling your own an interesting hobby . This is also the reason I am going to try casting my own starting with 9 mm and then for my .223 and .308. I sure hope my son gets interested or there is going to be some sale of reloading gear when I shuffle off this mortal world. Doubt there is much smokeless powder in the afterlife.

#7: Re: Hornady OAL Gauge and Comparator Author: Ominivision1, Location: Iowa

Posted: Wed Jun 27, 2012 2:18 pm
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MacD wrote:

I sure hope my son gets interested or there is going to be some sale of reloading gear when I shuffle off this mortal world. Doubt there is much smokeless powder in the afterlife.

#8: Re: Hornady OAL Gauge and Comparator Author: Dawgdad, Location: On the Prairie

Posted: Wed Jun 27, 2012 9:55 pm
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Eric stecker of Berger bullets wrote a nice article about jumping VLD bullets which everyone including him thought needed to be jammed into the lands to shooot well. i found this out by accident with 75 Amax in a223 where I mis read a caliper and jumped them .100 more and they shot great... here is the Berger article.

Getting the Best Precision and Accuracy from VLD bullets in Your Rifle

Background

VLD bullets are designed with a secant ogive. This ogive shape allows bullets to be more efficient in flight (retain more velocity = less drop and wind deflection). While this result is desirable for many rifle shooters the secant ogive on the VLD bullets produces another result in many rifles. It can be difficult to get the VLD to group well (poor accuracy).

For years we encouraged shooters to use a base of cartridge to end of bearing surface OAL (I will use the term COAL to represent this dimension) which allows the VLD to touch the rifling or to be jammed in the rifling. This provided excellent results for many shooters but there were others who did not achieve top performance with the VLD jammed in their rifling. These shooters were left with the belief that the VLD bullets just won’t shoot in their rifle.

Other groups of shooters were discouraged by our recommendation to touch the rifling. Some of these shooters knew that at some point during a target competition they will be asked to remove a live round. With the bullet jammed in the rifling there was a good chance the bullet will stick in the barrel which could result in an action full of powder. This is hard on a shooter during a match.

Yet another group of shooters who were discouraged by our recommendation to touch the rifling are those who feed through magazines or have long throats. Magazine length rounds loaded with VLDs could not touch the lands in most rifles (this is the specific reason that for years we said VLD bullets do not work well in a magazine). When a rifle could be single fed but was chambered with a long throat a loaded round that was as long as possible still would not touch the rifling.

Until recently, shooters who suffered from these realities were believed to be unable to achieve success with VLD bullets. Admittedly, we would receive the occasional report that a rifle shot very well when jumping the VLD bullets but we discounted these reports as anomalies. It was not until the VLD became very popular as a game hunting bullet that we were then able to learn the truth about getting the VLD bullets to shoot well in a large majority of rifles.

After we proved that the Berger VLD bullets are consistently and exceptionally capable of putting game down quickly we started promoting the VLD to hunters. We were nervous at first as we believe the VLD needed to be in the rifling to shoot well and we also knew that most hunters use a magazine and SAMMI chambers. Our ears were wide open as the feedback was received. It was surprising to hear that most shooters described precision results by saying “this is the best my rifle has ever shot.”

We scratched our heads about this for awhile until we started getting feedback from hunters who were competition shooters as well. Many were the same guys who were telling us for years that the VLDs shoot great when jumped. Since a much larger number of shooters were using the VLD bullets with a jump we started comparing all the feedback and have discovered the common characteristics in successful reports which gave us the information needed to get VLD working in your rifle. We were able to relay these characteristics to several shooters who were struggling with VLD bullets. Each shooter reported success after applying our recommendation.

Getting the Best Precision and Accuracy from VLD bullets in Your Rifle

Solution

The following has been verified by numerous shooters in many rifles using bullets of different calibers and weights. It is consistent for all VLD bullets. What has been discovered is that VLD bullets shoot best when loaded to a COAL that puts the bullet in a “sweet spot”. This sweet spot is a band .030 to .040 wide and is located anywhere between jamming the bullets into the lands and .150 jump off the lands.

Note: When discussing jam and jump I am referring to the distance from the area of the bearing surface that engages the rifling and the rifling itself. There are many products that allow you to measure these critical dimensions. Some are better than others. I won’t be going into the methods of measuring jam and jump. If you are not familiar with this aspect of reloading it is critically important that you understand this concept before you attempt this test.

Many reloaders feel (and I tend to agree) that meaningful COAL adjustments are .002 to .005. Every once in a while I might adjust the COAL by .010 but this seems like I am moving the bullet the length of a football field. The only way a shooter will be able to benefit from this situation is to let go of this opinion that more than .010 change is too much (me included).

Trying to find the COAL that puts you in the sweet spot by moving .002 to .010 will take so long the barrel may be worn out by the time you sort it out if you don’t give up first. Since the sweet spot is .030 to .040 wide we recommend that you conduct the following test to find your rifles VLD sweet spot.

Load 24 rounds at the following COAL if you are a target competition shooter who does not worry about jamming a bullet:
1. .010 into (touching) the lands (jam) 6 rounds
2. .040 off the lands (jump) 6 rounds
3. .080 off the lands (jump) 6 rounds
4. .120 off the lands (jump) 6 rounds

Load 24 rounds at the following COAL if you are a hunter (pulling a bullet out of the case with your rifling while in the field can be a hunt ending event which must be avoided) or a competition shooter who worries about pulling a bullet during a match:
1. .010 off the lands (jump) 6 rounds
2. .050 off the lands (jump) 6 rounds
3. .090 off the lands (jump) 6 rounds
4. .130 off the lands (jump) 6 rounds

Shoot 2 (separate) 3 shot groups in fair conditions to see how they group. The remarkable reality of this test is that one of these 4 COALs will outperform the other three by a considerable margin. Once you know which one of these 4 COAL shoots best then you can tweak the COAL +/- .002 or .005. Taking the time to set this test up will pay off when you find that your rifle is capable of shooting the VLD bullets very well (even at 100 yards).

Regards,
Eric Stecker
Master Bulletsmith

#9: Re: Hornady OAL Gauge and Comparator Author: Dawgdad, Location: On the Prairie

Posted: Wed Jun 27, 2012 10:02 pm
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also - most bullet makers can control the base to ogive measurment on a bullet to .001" within a lot but that number can be different between lots. If you really want to freak out take some high dollar hollowpoint match bullets and measure the base to ogive and then base to tip. Base to ogive will be dead on but ogive to tip will vary as much as 0.012" do not measure COAL to tip and expect any sizing die to get them the same overall length - but the jump will be the same for all.

If you plan to measure throat erosion be sure to keep a single bullet for that job as any change in the profile angle can result in a different dimension.

#10: Re: Hornady OAL Gauge and Comparator Author: slimjim, Location: Fort Worth TX

Posted: Thu Jun 28, 2012 5:21 am
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Thanks, Dawgdad! Your posts are always insightful.

#11: Re: Hornady OAL Gauge and Comparator Author: MacD, Location: Canada

Posted: Thu Jun 28, 2012 6:40 am
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Great info Dawgdad. I learned a lot. I am thinking of adjusting my load database to reflect COAL to ogive measurements. I can add to the remarks section of each Point Blank load. I have a sample empty round for all my best loads for ease of set-up of my seating dies. For me tweaking and tuning is what reloading is all about and now I have some more tests to run based on the article you quoted.

#12: Re: Hornady OAL Gauge and Comparator Author: MacD, Location: Canada

Posted: Thu Jun 28, 2012 8:49 am
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I am still reading and this is from the Barnes site. Scroll down to the Tips section and there is a short article on seating. They note that the Varmint Grenades like a close to lands position.

www.barnesbullets.com/...-bullet-n/

I also read some responses to the Berger bullet article. One point that was emphasized was not to use maximum loads when experimenting with deeper seating depths especially in smaller cases as pressures can change significantly and unexpectedly.

bulletin.accurateshoot...d-bullets/

#13: Re: Hornady OAL Gauge and Comparator Author: PaulS, Location: South-Eastern Washington - the State

Posted: Thu Jun 28, 2012 9:50 pm
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MacD,
there is another caution I would give to shooters working up loads with different seating depths:
Don't use minimum charges when seating bullets out further than the listed OAL...... I did that once with my 3006 and got a round that detonated after a 1/2 second went by from the drop of the firing pin. POP, sizzle and KABOOM! I thought I had destroyed my gun but after having it checked the gun was ok - the shell looked like it had a rim - if you can imagine a 3006 with a rim that sticks out like a 303 ..... scary.

#14: Re: Hornady OAL Gauge and Comparator Author: SingleShotLover, Location: Illinois

Posted: Fri Jun 29, 2012 4:50 am
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fnuser wrote:

Yeah I used to think you had to "cram it in straight" now I wonder if it don't hurt to "let it glide in natural".

With a "proper" chamber, you have a lot of leeway as to distance to the lands and still have good accuracy. Sloppy throats can let the bullet wobble a bit, making alignment problematic. A lot of custom chambers hold the throat to as little as .001" over bullet diameter making alignment a better bet. I think many of today's manufacturers might have actually tightened their tolerances. If so, good for them (and us!).

#15: Re: Hornady OAL Gauge and Comparator Author: MacD, Location: Canada

Posted: Fri Jun 29, 2012 9:18 am
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Good info Paul. I definitely want to avoid any kabooms.

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