.308 win Length for NK Sizing

[l115a3]

Could you please suggest how long should be NK Sizing for .308 win brass?



Most FL dies will nk sizing all the neck length but some article suggest only 1/3 of nk long.

I found that Redding Competition NK Sizing Die can adjust the nk sizing length by their Micrometer. So, how far should I resizing?


My fired brass measure .341" - .342" nk

My bushing was .336" nk


So, sizing nk diameter down .005" - .006" can be done within one step?

 

[Deadshot2]

Re: .308 win Length for NK Sizing

I don't bother with partial neck sizing. Even though I can adjust the amount of the neck that's sized I found that leaving that so called "centering collar" doesn't add anything to the accuracy.

When the cartridge is chambered the ejector on my rifle pushes the case against the shoulder area of the chamber and this centers the bullet in the freebore. Tests of partial and full neck sized cases showed absolutely NO difference in accuracy.

As for the proper bushing size, for a "tactical" or "field" load, I would use a bushing that gives .003" of neck tension. Any more and it just makes for more bullet seating pressure and the bullet acts like an expander. No gain from tighter necks beyond the .003" area.

To find the right bushing size, take a case and seat a bullet. Measure the outside of the neck and then subtract the amount of neck tension you want. For example, if I seat a .308 bullet in a case and measure .338" (common for my cases) and I want .003" of neck tension, I use a .335 bushing. If you haven't annealed the cases recently, and you get more "spring back" just go one size smaller.

To make sure my cases have uniform neck tension I then follow up with a mandrel type expander die. This insures an exact fit for the bullet and only minimal working of the case neck for increased case life.

 

[l115a3]

Re: .308 win Length for NK Sizing

I found that Redding Type S FL Die work my fired brasd too much on body.


Any choice for just nk sizing and bump the headspace without sizing the body?

 

[thespecialist]

Re: .308 win Length for NK Sizing

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Golfy Sniper</div><div class="ubbcode-body">I found that Redding Type S FL Die work my fired brasd too much on body.


Any choice for just nk sizing and bump the headspace without sizing the body? </div></div>

Forster makes a die that'll do just that

http://www.midwayusa.com/product/481804/...-308-winchester

 

[l115a3]

Re: .308 win Length for NK Sizing

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: thespecialist</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Golfy Sniper</div><div class="ubbcode-body">I found that Redding Type S FL Die work my fired brasd too much on body.


Any choice for just nk sizing and bump the headspace without sizing the body? </div></div>

Forster makes a die that'll do just that

http://www.midwayusa.com/product/481804/...-308-winchester </div></div>

Thanks, but seem like they only accept their bushing. Not for my Redding Ti Bushing.

 

[littlerascal56]

Re: .308 win Length for NK Sizing

Just back your Redding FL die out 1/2 turn and lock it down. It won't size the body..just the neck!

After a few firings, or when you can start feeling the bolt close hard, turn it back down and size the body.

 

[l115a3]

Re: .308 win Length for NK Sizing

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BigBore56</div><div class="ubbcode-body">Just back your Redding FL die out 1/2 turn and lock it down. It won't size the body..just the neck!

After a few firings, or when you can start feeling the bolt close hard, turn it back down and size the body. </div></div>


I would using Redding Competition Bushing Die for do only nk sizing.

But will use Redding Type S FL die for sizing the whole brass and also bump the shoulder back for .001"