Trim to what length - really

[Blackbrush]

My 308 chamber measures 2.044 and the books will have you trim to approx 2.015. My many times fired Lapua brass ranges from 2.019 to 2.034. I am happy to ignore the books and use what is best for my rifle. How much is to be gained by having all of my brass the same length v having my brass nearly/safely fill as much of the chamber as is prudent? The thing shoots 1/3 moa out to 600 with Berger 155s so it's no slouch.

Thanks guys.

 

[justinbaker]

Re: Trim to what length - really

the important thing is to have them all the same length. so maybe trim em all back to 2.019

and then from there, dont trim again till they get close to your chamber length

here is the thread i asked on this topic a while back

http://www.snipershide.com/forum/ubbthre...839#Post3061839

 

[Leaddog]

Re: Trim to what length - really

Why not just trim to SAAMI? 2.005 is minimum and 2.015 is max. No need to experiment outside of spec.

 

[justinbaker]

Re: Trim to what length - really

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Leaddog</div><div class="ubbcode-body">Why not just trim to SAAMI? 2.005 is minimum and 2.015 is max. No need to experiment outside of spec.



</div></div>

because you dont need to trim the neck more than whats necessary.

http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1696162#Post1696162

 

[Blackbrush]

Re: Trim to what length - really

Thanks guys. I appreciate your responses.

All due respect Leaddog, if all we ever did was go SAAMI, we'd miss out on a lot of successful (and unsuccessful) experimentation that leads us to improvements. Plus what's the fun in that!?!? Thank you for your service sir.

I will likely trim to 2.020 which still leaves me a long way from being too long at 2.044. At least we'll be consistent in length again.

 

[MitchAlsup]

Re: Trim to what length - really

If I remember correctly, you need at least 0.006" of longitudinal clearance on the case neck. This allows some room for the neck to expand longitudinaly under pressure and not run into the end of the throat--grab onto the bullet--dramatically increasing pressure.

Since you have a known measured length, you can leave the encks as long as you like.

However, I don't remember anyone stating that realy long necks add to accuracy. The necks only need to be a caliber in length for proper grasp of the projectile.