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neck sizing question
joes
Member Posts: 484 ✭✭✭
I have a weatherby mark v in a 308 that shoots ok but I would to try to improve the groups by neck sizing. I have read here that I can neck size the brass with full length dies by back off the dies. This is what I did, let me know if I did this correctly. I backed off about eight turns ( maybe 1/4 in) ran them through the dies and seen marks from the die about 3/4 of the way up the neck. I am using lee dies, and a Lyman all american press. Thank you! Joe
Comments
What your trying to NOT see is evidence of the die touching the body or shoulders of the case. Depending on how sloppy your chamber is, and how tight your die is, you may still see the body of the case being sized slightly, no matter how far up your adjusted.
Now, as far as how you adjusted your die, I'm a little confused. The threads are 7/8-14, so 8 turns up would be close to 9/16", not "maybe 1/4". From your "normal FL" setting, raise the die 1-2 full turns and lock it there (or get a couple 7/8" flat washers and simply place them under your locknut, that's the easy way when your using nuts with lock screws on them)
I measure how far into the case I am seating the bullet and that is as far as I neck-size.
Now I always use the same case in the same rifle, and often my bullets are seated quite a ways out in the neck in order to get closer to the rifling. I always single load, instead of using the magazine.
This is fine for target shooting but probably not so good for hunting, where recoil might move the bullet around in the case.
The theory behind doing it this way is two-fold: it may give better accuracy if your bullet does not have to jump as far to the rifling, and the unsized part of the neck will help center the bullet in the chamber.
This method is not suitable for hunting, I think I would follow the advice if the other responders, but it works well for me in punching holes in paper.
Sizing to depth of bullet base? Damn. Why didn't I think of that? I've thought about the advantage of the centering effect of the "second shoulder" but by force of habit just kept sizing to just shy of pushing back the shoulder.
Thanks