Full length resize or neck size only for y'all long range hunters?

[Old teacher]

I neck size almost all of the cartridges I reload, but have never worried much about the shoulder bumping issue. The whole idea, as I see it, of neck sizing is to produce a case that fits perfectly into your chamber. I have three 300 Win mags, and the differences in chamber size and shape among the three is significant. Full length sized cases with RCBS dies produces a case which will work in all three guns, but obviously fits none of them well, hence the neck sizing. I keep all cases in boxes labeled for each rifle. The 300 WM sized full length headspaces on the belt; neck sizing produces a case that headspaces on the belt AND the shoulder. Bumping the shoulder back affects that and you lose the added cartridge stability in the chamber, thereby affecting accuracy. As long as the case fits nicely in the chamber when the bolt is closed, why would you want to bump the shoulder back? I set my neck sizing dies to stop right where the neck and the shoulder meet, and I have never had any problems.

 

[gebhardt02]

I too have a couple different rifles for the same cartridge, but I FL size them all. I set my dies up differently than some folks though as I set the die to FL size but only bump the shoulder back 0.002" or so. I set the die for the rifle that needs the shortest case after sizing and then use some machine die shims to get the proper height on the other rifles cases. This way I take the time to set my die and just annotate in the log books which cases need the shims, and never have to worry about cases getting too tight in the chamber when neck sizing only and I also don't overwork the cases. One FL die for each cartridge, minimum bumping of the shoulder, and the cases aren't exactly a "sloppy" fit in the chamber either.

Geb

 

[COBrad]

I reload my 22-250 on a Dillon progressive press. The progression is; 1. neck size and deprime. 2. powder charge. 3. bump shoulder .002. 4. seat bullet. Dies are Redding, and the neck sizing and seating die are competition dies.
The gun still shoots .5 MOA. A few thousand rounds ago, when the barrel was fresh, it shot in the .3's.

 

[LDHunter]

Yep.... I've got a Dillon XL650 and have loaded some scary accurate ammo on it...

 

[Marlinproud]

I neck size almost all of the cartridges I reload, but have never worried much about the shoulder bumping issue. The whole idea, as I see it, of neck sizing is to produce a case that fits perfectly into your chamber. I have three 300 Win mags, and the differences in chamber size and shape among the three is significant. Full length sized cases with RCBS dies produces a case which will work in all three guns, but obviously fits none of them well, hence the neck sizing. I keep all cases in boxes labeled for each rifle. The 300 WM sized full length headspaces on the belt; neck sizing produces a case that headspaces on the belt AND the shoulder. Bumping the shoulder back affects that and you lose the added cartridge stability in the chamber, thereby affecting accuracy. As long as the case fits nicely in the chamber when the bolt is closed, why would you want to bump the shoulder back? I set my neck sizing dies to stop right where the neck and the shoulder meet, and I have never had any problems.

How many times have you fired this brass in these rifles? There comes a time when it becomes difficult to close the bolt on these cartridges and then youre forced to bump back the shoulders.

 

[LDHunter]

I can tell you that I normally just toss brass when I reach the point I'd have to bump shoulders... Of course it varies but usually between 4-10 loadings and by then I'm usually thinking I want to toss them anyway.... I think the number of loadings I usually get out of brass is 5-6.

I currently don't load for any super mags or wildcats where brass is very expensive or hard to find so I may be annealing, and bumping and neck turning in that scenario... Fortunately I have never had to and that's part of why I'm not much of a wildcatter. I just have the time for all that "stuff".... LOL

Bob

 

[Old teacher]

Marlinproud: most of my .300 brass is in the fifth or sixth loadings. (Nosler brass) I have never had a cartridge labeled for a particular gun not fit into the chamber. Perhaps the neck sizer is set low enough that I am bumping the shoulder back a little without knowing it. It is difficult to get a really accurate measurement on a shoulder, but I will measure a few and see if I can notice any discernible difference. I do know that my accuracy increased in all three guns when I switched from full length to neck sizing. The whole point, I assume, of neck sizing is to create a case that fits perfectly into your chamber with no slop anywhere. One of the knocks on belted cases is that they headspace on the belt, not the shoulder, making them a little unstable in the chamber prior to firing. Necksizing, if you do not bump the shoulder back, creates a belted case that will headspace on the belt and the shoulder, creating a very stable situation in the chamber. Bumping the shoulder back creates a space between the shoulder and the front of the chamber, negating the advantage of necksizing . But, you are right about the fit. If the bolt won't close, the whole process becomes pretty moot.

 

[COBrad]

Except for rounds I load on the progressive, I don't bump shoulders until the bolt gets stiff upon closing. I can tell you bumping the shoulder one or two thou. does not adversely affect accuracy. Case in point; I bump the shoulders on a custom 7 mag varmint rifle .002 when necessary, and those rounds were used last weekend to take a marmot at 1332 yards. The have been used to take over a dozen more at ranges between 900 and 1200 yards.
Another thing I do when I neck size is only size about 80% of the neck. I leave the remaining bit above the shoulder untouched and it will fit the chamber perfectly.

You can accurately measure base to shoulder length by using tools from Stoney Point or Sinclair made to measure from the datum line... but you probably already know this.

 

[Marlinproud]

Marlinproud: most of my .300 brass is in the fifth or sixth loadings. (Nosler brass) I have never had a cartridge labeled for a particular gun not fit into the chamber. Perhaps the neck sizer is set low enough that I am bumping the shoulder back a little without knowing it. It is difficult to get a really accurate measurement on a shoulder, but I will measure a few and see if I can notice any discernible difference. I do know that my accuracy increased in all three guns when I switched from full length to neck sizing. The whole point, I assume, of neck sizing is to create a case that fits perfectly into your chamber with no slop anywhere. One of the knocks on belted cases is that they headspace on the belt, not the shoulder, making them a little unstable in the chamber prior to firing. Necksizing, if you do not bump the shoulder back, creates a belted case that will headspace on the belt and the shoulder, creating a very stable situation in the chamber. Bumping the shoulder back creates a space between the shoulder and the front of the chamber, negating the advantage of necksizing . But, you are right about the fit. If the bolt won't close, the whole process becomes pretty moot.

My 308 Lapua brass did 10 firings with just necksizing but got really hard to close the bolt. I had to fl size them to bump the shoulders back but then accuracy changes. Im looking at getting a Forster body die in the future. I also thought by necksizing the whole neck with my redding necksizer im bumping the shoulders but thats not true. I also now only size 2 thirds of the neck when necksizing, then you have a nice fit and no blowback on the cases.

 

[4bycamper]

. I also now only size 2 thirds of the neck when necksizing, then you have a nice fit and no blowback on the cases.

Really? Thanks, I'll try it.

BAM - Learned something !

 

[Ridgerunner665]

One of the advantages of of the 30-06 shoulder angle...I resize to .000"-.001" headspace, no bumping the shoulder...brass lasts a little longer.

Learned that from an article by German Salazar...

2. Headspace. The longer a case is, and the more tapered it is, the more it will grow each time you resize it; and the more it grows, the sooner you will run into a case head separation. With modern case designs such as the .308 or the 6BR both of which have moderately sharp shoulder angles and straight bodies, you need to set the shoulder back 0.002" or so in order to ensure easy bolt operation and to avoid galling the locking lugs and seats. The .30-06, however, with its mild shoulder angle of 17.5 degrees and it's long, tapered body, works just fine with a 0.000" setback. This isn't the same as neck sizing, because you're still sizing the whole body. However, if you work carefully, you can set your die for 0.000" to 0.001" setback, extend case life a little (I get 11 to 13 firings from most of my brass) and maintain reliable functioning.

 

[Clever]

I use the the Redding FL sizing die then the Redding neck sizeing die without the decaping rod removed. Been getting great results.

 

[Old teacher]

What advantage do you gain by FL sizing and then NS? Once you have run the case through the FL die, the neck has been sized. The whole point of just neck sizing is to create a case that exactly fits your chamber. If you stretch a case to the point that the bolt has trouble closing, then you bump back the shoulder about .002. Full length sizing merely creates a case that the die manufacturer may or may not have created to match the "official" specs of the case. "Not" is most often the situation. I have had to send a half dozen or more dies back to the manufacturer to be adjusted to be the correct size, and then the case may still, or rather will not match your chamber. Neck sizing guarantees that your case will exactly match the chamber of your rifle, and the only issue is stretching cases requiring the bumping. Since a neck sized case exactly fitting your chamber has no where to go when it tries to stretch, bumping the shoulder back on a regular basis makes neck sizing a moot point. You have lost part of the advantage you have tried to gain by neck sizing in the first place. I have never had to bump a shoulder back in my life,, but you do need to make sure you keep your cases trimmed to the proper length. I not only do not bump shoulders back, but I set my neck sizer so that it leaves about .002 or .003 of the neck unsized. Even doing that, I have had no problems closing a bolt. It is just logical common sense that the tighter the chamber of your rifle holds the case, the more accurate the rifle will be, especially if the case is belted. Lots of guys have said that their rifles are just as accurate if they bump the shoulders back on their cases, and many have more experience than me, but I would bet that if we measured groups into the thousandths or maybe into the ten thousandths, the non-bumped cases would be more accurate. Now, does that small a difference make any difference in the real world? No.

 

[Clever]

What advantage do you gain by FL sizing and then NS? Once you have run the case through the FL die, the neck has been sized. The whole point of just neck sizing is to create a case that exactly fits your chamber. If you stretch a case to the point that the bolt has trouble closing, then you bump back the shoulder about .002. Full length sizing merely creates a case that the die manufacturer may or may not have created to match the "official" specs of the case. "Not" is most often the situation. I have had to send a half dozen or more dies back to the manufacturer to be adjusted to be the correct size, and then the case may still, or rather will not match your chamber. Neck sizing guarantees that your case will exactly match the chamber of your rifle, and the only issue is stretching cases requiring the bumping. Since a neck sized case exactly fitting your chamber has no where to go when it tries to stretch, bumping the shoulder back on a regular basis makes neck sizing a moot point. You have lost part of the advantage you have tried to gain by neck sizing in the first place. I have never had to bump a shoulder back in my life,, but you do need to make sure you keep your cases trimmed to the proper length. I not only do not bump shoulders back, but I set my neck sizer so that it leaves about .002 or .003 of the neck unsized. Even doing that, I have had no problems closing a bolt. It is just logical common sense that the tighter the chamber of your rifle holds the case, the more accurate the rifle will be, especially if the case is belted. Lots of guys have said that their rifles are just as accurate if they bump the shoulders back on their cases, and many have more experience than me, but I would bet that if we measured groups into the thousandths or maybe into the ten thousandths, the non-bumped cases would be more accurate. Now, does that small a difference make any difference in the real world? No.

I have tried many different ways of sizing my brass. I agree with you and have not ever bumped the shoulder Where I don't agree is the total neglect of neck tension in your protocol. Fire forming and just neck sizing I agree is normal practice. In my case the brass fire forms in a different way. In my chamber the brass becomes larger towards the rear and the shoulder does not move. No matter what powder charge I use low or high the outcome is the same. So I FL size and deprime then neck size without the rod. I trim to my chamber dimention rather than SAMMI, and let the brass for for 24 hours as it will snap back. Since my brass swells towards the rear my bolt would stick. I would still follow advise from people like you. Besides the obvious I noticed that the to maintain proper FPS I would need to increase my powder charge. It only got worse as I refused to think outside the box and my Rig is a Sako TRG 42 338 Lapua Mag. I only use the best: Lapua brass, Scenar Projectiles, Federal Magnum Match primer and Redding Competition Dies. In conclusion I determined that my brass is fire forming in a way where normal sizing practice did not work. So I FL size then remove de-capping rod form neck sizer and neck size for proper neck tension. Trim to my rifles dimension and let them sit for 24 hours as they will snap back.
Just a word of advise: Don't jump the gun and criticize other reloading procedures. As you should know and have been around for a long time not all rifles are the same. They will produce different results depending on your approach.. My rifle shoots lights out!! Period!! And I am the one that figured out what it takes.. Normal reloading procedure is NOT always the best way to achieve long range accuracy.. Sometimes thinking outside the box an a good attitude towards trial and error WORKS. Keep in mind there are people learning from us..