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Re: Shoulder set back 308
Posted: Sun Dec 25, 2011 2:40 pm
by EagerNoSkill
Neck turn noted :-; going slow with that
Will measure all first then decide
Primer pocket too late .... New tools had to be used blooded :shakeshout:
Re: Shoulder set back 308
Posted: Sun Dec 25, 2011 2:53 pm
by 20series
You shouldn't need to neck turn!!
The chamber should be a standard SAAMI spec otherwise it doesnt fall within the F-TR rules!! which is the intent with your rifle when you get it isn't it??
Re: Shoulder set back 308
Posted: Sun Dec 25, 2011 2:56 pm
by spud
valid point made alan
Re: Shoulder set back 308
Posted: Sun Dec 25, 2011 3:20 pm
by ovenpaa
That is not why you might neck turn in F/TR or even other disciplines.
There are slight differences in neck thickness from case to case, manufacturing tolerances and even the machine they come off will have an impact on this, it may be a few tenths of a thou but there will be a difference from case to case, this in turn will make a slight difference to neck tension which will impact verticals so you neck turn the absolute minimum to uniform the necks of the cases. This is usually a few tenths.
Re: Shoulder set back 308
Posted: Sun Dec 25, 2011 3:21 pm
by EagerNoSkill
Chamber is standard SAAMI
Primary reason to to get uniform neck thickness that helps lead to uniform neck tension on bullets
Buying lapua is intended to reduce the scope of neck wall variations but some variations may exist
Hence the check
Re: Shoulder set back 308
Posted: Sun Dec 25, 2011 3:22 pm
by EagerNoSkill
Oops just saw overpaa's answer
Better than mine sign92
Re: Shoulder set back 308
Posted: Mon Dec 26, 2011 11:42 pm
by alexham
EagerNoSkill wrote:To fl resize a case what is the goal 0.0010 inches from SAMMI spec
If you screw down the F/L resizing die until it bottoms out on the case holder it will get you very close to the SAAMI specification, but why do you want to do that? SAAMI specification rounds are meant to chamber in a smallest chamber, without causing excessive headspace in the largest. On first firing the case is fire-formed to the dimensions of your rifle's chamber and the best accuracy is achieved by only neck sizing. You can achieve that with a F/L die if you screw it down until it bottom out on the case holder and then turn it back half turn. Load a few rounds and check that the bolt closes easily, before proceeding to load a large batch.
Alex
Re: Shoulder set back 308
Posted: Tue Dec 27, 2011 9:38 am
by Christel
Alex, welcome to the forum

Re: Shoulder set back 308
Posted: Tue Dec 27, 2011 2:28 pm
by alexham
christel wrote:Alex, welcome to the forum

Thank you Christel.
Alex
Re: Shoulder set back 308
Posted: Tue Dec 27, 2011 10:13 pm
by EagerNoSkill
Hi Alex
Primary reason was that I had a variety of good (well goodish) brass that had NOT been shot in my gun but in various NRA club guns over the last few months.
I cant get myself to throw away good brass and for my training at 300 to 600 yards - well preped brass would suffice initially.
To accurately neck trim the brass (varied cases RWS and HPS brass in different guns)
the optimal process is:
1. FL resizing,
2. trim to uniform OL and
3. then neck trim to uniform neck case wall thickness.
Once this is done and the brass is fired in the chamber of my gun it should only require neck sizing (this I plan) with some shoulder press back after several loads