Another basic question. I shoot .308 through my M1A and am focusing on 600+ yard shooting.

Does anyone feel like giving their opinion on Neck Sizing versus Full Length? My observations and measurements prove that the FL sizing only runs down to within xxx" of the bottom of the case. I feel this is beneficial and have not bought any low profile shell holders since I believe leaving that bottom portion unsized it aids greatly in centering the round in the chamber.

I understand it will depend on chamber size but what is the real benefit with neck sizing? I might assume it may increase the longevity of my brass. Is this true? Does it help that much more in terms of centering the round? Would annealing be necessary more or less often to extend the integrity of shoulder area for safer, longer lasting brass? Any insight or elaboration on the pros/cons of the different methods would be appreciated.

Thanks,
XWind

Xwind,
Neck sizing is NOT recommended for autos, levers and pumps. They don't have the heavy camming that the bolt actions do. It is usually recommended that the use of "Small base" or "Ultra-small" base dies be used to eliminate feeding problems - especially in the Brownings. If your weapon tolerates the use of standard dies - so much the better for you.
In a bolt action, neck sizing only will give you a round that "fills" the chamber better than a full length sized case and if the neck is only sized two thirds of it's length then the round will center in the bore better than full length sized or neck sized cases that are sized all the way to the shoulder.

PaulS

PaulS, Thanks for the info. Doesn't resizing only the neck, and not down over the shoulder, change the headspacing on rimless rounds like a .308 and many others? Do the bolt gunners only resize enough to get their neck tension back? It seems to me that by not sizing down to at least the shoulder you will shift the datum line (.040") in my situaton therby altering the headspacing. Am I trotting down a bunny trail or is there some merit to my concerns? I really didn't realize I was fortuneate that my auto loader would accept rounds that didn't resize way down onto the base but I do fimd it advantageous in terms of centering the round as mentioned.

One of the things I'm struggling with is getting the most number of firings out of my brass (trying to reach 'break even' on my investment in reloading equipment). I can 'see' without measuring that my cases are larger after being fired than after being resized (FL). With all of the info I've read and heard about indicates that FL sizing will give you the minimum number of firings before the brass is wore out due to stretching, thinning etc. I have to trim to minimum after every two firings with my Win brass so I'm obviously losing metal in the process of FL sizing.

Do you or anyone reading this thread have any experience with the RCBS X-Dies? Maybe that's the way I should go to increase the life of my brass based on their claim to being able to maintain OAL. Again any thoughts or ideas are welcome and appreciated...

XWind

I gave up on standard dies, I have found that full length sizing with a die made for your chamber is much more accurate than neck sizing. You will be sizing that case to your chamber and can control neck tension with the bushings. Almost all of the bench rest guys are Full length sizing with bump/custom FL dies. Every round chambers the same, it reduces fliers. But these dies can be expensive, but I feel well worth the cost .

If you're shooting M1A, you need to get yourself a "Mo Gauge". It's a combination case length and micrometer head space gauge. You adjust your full length sizing die to your spent case from your rifle.

"Take a reading on the actual fired case and then adjust your sizing die to the .001" smaller than the reading you got on the fired case. (.002 for service rifles)." From: Highpower Rifle Shooting, pg. 53, Case preparation by M. Tompkins.

I use the "Mo Gauge" to reload .223 on LH Tikka Whitetail Hunter, which shoots ragged one holers.

All your trying to do is adjust your sizing die just enough so that there is no slopp when you chamber a round. The round will fit your chamber like a glove. Not too tight and not too loose. Just another idea that you might to try.

Here the address to get your own MO-Gauge: MCS, Inc. 34 Delmar Dr. Brookfield CT. 06804 Ph# (203) 775-1013

[ 01-03-2003, 08:57: Message edited by: CK ]

I found in many cases that FL sizing works the shoulder forward enough that if you don't come down enough and bump the shoulder a fired case that rechambers easily now will not at all.

The MO gauge is certainly a good idea, doesn't redding have something like that with a dial indicator on top or is that something else?

My MIA worked well FL sizing too. I never bothered with tightening it up though, just FLd them all.

One option that might be good is to partially size w/FL die. With my .30 Gibbs I size .250" of its .300" (don't bother sending posts that my Gibbs is .005" short, this was intential). For my hunting situations this enables easy chambering while enjoy a tight neck which in my rifle is well centered with the bore contributing to very good accuracy. I would think that this approach would help a auto chamber while still allowing a tight neck. If the round does not chamber well simply size more of the neck until it works (you have approx .003" of more neck than I do to play with). Can't comment on the head spacing aspect of the .308 though.

Deke.

X-Ring Give Neil Jones a call 814-763-2769 You will need to send some fired cases, he will make you a die for your chamber only. Tell him Frank Genovese told you to call him. These dies don't come cheap! But they are well worth it. Using his dies cut my groups almost by half.