Really, another variable, turning necks?

[coblenblueface]

Ok, first off I am a competition shooter in Germany. I shoot a 1941 Husky M38. That said I have been told to turn necks both here and at the range. On many forums I have gotten the same but not a single person has said why. WHY turn necks? I understand it has something to do with neck tension but I have seen enough posts that say, 'don't bother', to be a lil confused. Can someone give and a clear (and its ok if it a bit technical) answer? Anything that can increase my score is worth hearing about.

 

[BoydAllen]

First of all, I have an M38 that is in good shape and very accurate, so I am familiar with your rifle and its caliber. Secondly, American brass is, on average, not as good as the best from Europe (Norma, Lapua, RWS) so for some of our brass, in some of our chambers (if the neck clearance on loaded rounds is not too great) there may be an advantage in making necks' thickness more uniform, to promote more consistent grip on bullets, as judged by seating force. I would expect that these sorts of improvements would show up as reduced velocity spread. Based on my experience, I suspect that there would be little go gain by turning necks for your rifle, but there may be some small gain to be had at long ranges by doing some careful annealing. I say this not so much because of my 6.5x55 experience, but because of experience that I have had helping others with their rifles. The trick it to not over soften the necks. What kind of loads have you been using, and what kind of accuracy? My best results have been with IMR 4350 and 100 gr. Sierra Hollow points, as well as with H4831 and Hornady 160s. loaded to the cannelure.

 

[GPat]

Here's some reasons to turn necks:

1) If your chamber requires it. For example: a 6mm PPC with a .263 neck diameter chamber requires you to neck turn for clearance in the chamber.

2) To uniform the neck wall thickness. This has a few benefits:

a. Uniform necks yield better concentricity in your loaded rounds since one side of the case neck is
not thicker, the bullet is not being pushed to one side of the loaded round more than the other.

b. Uniform necks yield more consistent neck tension, basically an extension of "a".

c. Uniform necks yield a cleaner and more consistent bullet release when fired.

3) To be able to use and get the most performance out of bushing style sizing dies. Neck turning
along with using bushing style sizing dies lets you eliminate the button in your sizing dies,
reducing case stretch and also improving concentricity.

All of those should add up to better accuracy in nearly every bolt action rifle. I'm sure some of the guys here can add to this, but those are (in my personal opinion) the main reasons.

 

[treeman]

turning necks can help neck tension be more consistent but annealing necks may help even more especially if they have been sized several times