Bolt face issues will not create lack of concentricity as such. Unless cartridges are loaded to such maximum dimensions that they are jammed into a chamber, the fit between bolt-face and cartridge head head is somwhat loose due to extractor issues and etc. The chamber controls alignment. If a bolt face is off-square it might create a support problem, which would probably cause accuracy issues, but not alignment. Even assuming a"perfect" chamber, a bullet that is even slightly out of perfect alignment will enter the rifling at a slight angle causing the bullet to not be centered in the bore. Granted, this is a miniscule amount, but effects down range can be dramatic.

The only problem I've noticed with Lee dies is the seaterplug. It dosent fit all bullets. Some, it will leave a ring close to the tip. Lee will make a custom plug to exactly match your bullet, but I havent went thru that trouble yet. It may be worth it though. With my '06, I only have 1 so I could use my Lee collet dies and just neck size. That wouldnt over work the brass. I used to neck size my 270 brass, but now I have 2 rifles, so I'd have to keep the brass seperate. That may be my next experiment, see if there is any difference between neck size'd and FL resized groups. 300 yards should be long enough to see any difference. Maybe I'll get rid of the flyer once in a while.

Well stated SSL. I will add two things. Every time you fire the case, it becomes concentric again as it expands out in the chamber/bore. Its the reloading process the gets it out of alignment. Size the neck down, expand it back out (if not an S-type die), and seating the bullet if not held in alignment. The case can become and issue. Over time the neck thickness will begin to vary by more than a couple thousanths (thick sections do not stretch as much as the thin parts). Once the variation exceeds 0.003, it might be worth tossing it and starting with a new case.

DSlayer, the over-work brass occurs when the case goes into the die then the expander ball enlarges it. Take your expander ball out and run a case through. Measure the neck and see how much undersized it is. Now you see how much the expander ball has to expand the neck back out. With a Redding S-Type die, you buy the bushing the will size the case neck down to what you need - the minimum required. I'd be interested if you would post your numbers. Do you know how to adjust your FL resizing die to fit your chamber? My 130gr GMX load groups best with neck-size only ($20 Lee hand loader). My 129gr LRX groups best with full-length resized.

Slim, yes I do know how to adjust the FL die for my chamber. I'll have to measure a case and get you the numbers. On another note, my chamber, well throat actually, is so long that 130 grain bullets or smaller will NOT touch the rifling. Even 135 SMK's wont. 140's and 150's will. Just kinda odd if you ask me. Thats a remington 700. My browning x-bolt and winchester 70 has very short throat's.

All I can talk about is my own experience. I have been loading since 1971 but the first two years I used the Lee loaders in the box. Even with the little Lee loaders I made ammo that was sub- one inch groups at 100 yards. (this in a sporterized 03A3). Once I got my press and started into reloading I had a heck of a time getting small groups until I started neck sizing again. I started neck sizing because I got a few "J" splits (body splits that ran up and down the case) and realized that my chamber was so big (military) that I was working the brass too much sizing it. That helped but I started just partially neck sizing - size just the first 60 to 70% of the neck and leave part of it expanded so it fits the chamber better - that's when my groups dropped to 9/16" to 5/8" at 100 yards. I shoot five shot groups instead of the "normal" three shot groups just because I use five shot groups with my revolvers. I like everything "standardized" I guess. Anyway the partial neck sizing keeps the bullet better aligned with the bore than when it is resting on the bottom of the chamber - at least that's the reason I use. The case is expanded to fit the chamber and the rear of the neck is too. It just makes sense to do it that way - especially when it works so well for me. I load the same way for all my guns - bolt action and break-open. I hear stories of having to "push" the shoulder back so the cartridge will chamber but I have never had to do that and I believe that would be a sign of excessive pressure. The brass will only expand to the size of the chamber and the harder the brass gets the better spring it is - right up to the point of cracking. I've not had any problems even after loading a case 20 times and more. I don't experience heavy bolt lift and my fired cases will fall into the chamber under their own weight. I never exceed maximum listed loads and I rarely use maximum loads. Most of my loads run at 95 to 97% of maximum listed charges. I load for accuracy and the velocity takes care of itself. I don't use my chronograph until I have an accurate load worked up already. Then I use the chronograph to get the velocity so I can work out my 1" point blank range. I use ballistics software - like Point Blank - to approximate my adjustments for extended ranges but I shoot at those ranges to find out where my bullets are actually impacting at those extended ranges. The software gets you close but I have seen deviations as high as 2.5" at 300 yards.

Every rifle is different and what works for me may not be necessary or even of any value in another gun. Target chambers, by design, do the same thing that partial neck sizing does because clearances are held so much tighter. I just don't have any rifles that have target chambers - or even tight chambers.

When you do find something that works then keep doing it. Going from full length sizing to neck only sizing takes a few firings to get the case where it is an ideal fit in the chamber so try it for a while before you decide it doesn't improve anything. You may even have to adjust your loads due to the extra space in the swelled case.

Have fun with it, take your time to se what works to improve your groups and enjoy!

Paul

OK, measured brass necks with and without the expander plug. The difference is .006" with a Lee FL die. I dont think that is too bad.

DSlayer, my .308 brass would be neck-sized down 0.005" with an S-Type/Bushing die (that distance depends on the individual chamber, some more, some a thou less). With a standard expander-ball die that would be neck down 0.011" then expand back out 0.006". The numbers may be small but the relative magnitude is, IMO, significant (3x) and work-hardends the brass more. If you don't anneal your case necks, this adds up.

Slim, how do you aneal your cases? I've been told to chuck it in a drill and heat the neck with a propane torch until it just starts to turn red. Then quench the case in ice cold water. I do this in a dark room so its easier to see when the brass starts to get red. It makes a nice discoloration just past the shoulder. If you do it too long, the discoloration gets really close to the case head, and that case gets tossed.

Donut Slayer wrote:

Slim, how do you aneal your cases? I've been told to chuck it in a drill and heat the neck with a propane torch until it just starts to turn red. Then quench the case in ice cold water. I do this in a dark room so its easier to see when the brass starts to get red. It makes a nice discoloration just past the shoulder. If you do it too long, the discoloration gets really close to the case head, and that case gets tossed.

Here ya go DS...put your mind to building this machine mate...

Case Annealing

Personally, I use the warm fingers approach...hold the neck of the case in a propane flame and when the base of case get a bit hot around the fingers it is pretty much right. Ity's slow, but it works well.

Vince wrote:

Personally, I use the warm fingers approach...hold the neck of the case in a propane flame and when the base of case get a bit hot around the fingers it is pretty much right. Ity's slow, but it works well.

Same here. Plus it keep you from over-heating the brass. That can cause damage too. I have also heard of people standing cases in a shallow pan of water, heating the necks with a propane torch and then tipping them over to quench. Haven't tried it, but might be a way to prevent blistered fingers!

SSL, that works OK. I use a small aluminium pan I found in an old fridge (to make ice-cubes). For me it works best when I deprime the cases before annealing, so that the water can enter inside the case. Easier to dry them afterwards also. A tip: don't use the blue innerpart of the propane flame. The flame is the hottest about 1/2" before the blue innerpart + somehow that blue unburned propane likes do perform a chemical reaction with the brass.

Donut Slayer wrote:

Slim, how do you aneal your cases?

I do not anneal my brass. I use a Redding S type bushing die so I don't work harden the brass.

Sorry, was in a big hurry, well not me but the other more important half. But, I saw and read the above site and found it very interesting. Not that the automated systems were not cool, But, I like simplicity. I have some more questions and comments about alignment of projectile to cartridge, and especially about the squareness and perpendicularity of the bolt face to the center-line of the bore, but don't have the time today.

With the cost of LPG or propane these days, I want to use only one burner, which means rotating the case. I like the idea of the rotating holder... Wonder if a case turner could be incorporated? Hmm, food for thought.