Head space and case trimming

[Thor2j]

I'm currently neck sizing only with Redding s type bushings. My questions are should I wait until I have tension while closing bolt before I bump the shoulder back with my body die?
After 5 firings with Lapua 308 brass, no problems with bolt.

I want to trim to a uniform length, using 2.008, but if the shoulders are not exactly the same, aren't I actually making different neck lengths, thus different tensions??

Would it be best to bump shoulder back .003 after I have bolt issue and use that as my new headspace??

Thanks, and I have had better luck with neck sizing only vs full.

 

[427Cobra]

Re: Head space and case trimming

Any and all benefits from NS only are negated when you show up at the range/match/hunt and your ammo won't chamber, a properly setup FL die that bumps the shoulder back .001-.0015 will produce ammo that is just as accurate as ammo that that was made from NS only.

As for trim lengths, Sinclair sells a chamber length gauge, you modify a sized case by trimming .100 off and insert the gauge in it, chamber it and it will give you your chamber length, I trim .010 from the reading, 2.008 is probably .030 or more from the end of your chamber. I don't know of any shooter that shoots Precision Rifles that can shoot the difference, ammo that is +/-.010 trim lengths all shoots the same.

 

[milo 2.0]

Re: Head space and case trimming

Your COAL will still be the same length, that is dictated by you seater plug, not case length.
Hope this helped.

 

[gunsnjeeps]

Re: Head space and case trimming

Depends on your trimmer. I trim with an RCBS. It is overall length, I think the Giraud sets from the shoulder.

 

[ksthomas]

Re: Head space and case trimming

Thor2j,

You're worrying way too much about your length. As others have pointed out, theres a pretty good bit of latitude here. It may, and I stress <span style="text-decoration: underline">MAY </span>become a safety issue if you let them go much beyond the 2.015" SAAMI max. As to its effect on neck tension, totally negligable, don't sweat it at all.

I'd suggest trimming to 2.000" even, and forget about it for the next several firings. And for what it's worth, I'm completely with Cobra427 about the Neck Sizing; it's an invitation to trouble, and Murphy will pretty much guarantee that it'll find you at the worst possible time. You give up nothing in terms of accuracy <span style="text-decoration: underline">or </span>case life by FL sizing, so long as it's done properly. And it will steer you well clear of Murphy, which is always a good thing.

 

[winxp_man]

Re: Head space and case trimming

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: 427Cobra</div><div class="ubbcode-body">Any and all benefits from NS only are negated when you show up at the range/match/hunt and your ammo won't chamber, a properly setup FL die that bumps the shoulder back .001-.0015 will produce ammo that is just as accurate as ammo that that was made from NS only.

As for trim lengths, Sinclair sells a chamber length gauge, you modify a sized case by trimming .100 off and insert the gauge in it, chamber it and it will give you your chamber length, I trim .010 from the reading, 2.008 is probably .030 or more from the end of your chamber. I don't know of any shooter that shoots Precision Rifles that can shoot the difference, ammo that is +/-.010 trim lengths all shoots the same.

</div></div>


Good points here about not being able to chamber! And yes you have to watch out when neck sizing. I usually run a few cases from that current batch through the rifle and that tells me if everything will be good. I never had a problem doing my reloads like I just stated.



Aron-