how many times until a case trim?

[Recusance]

Originally Posted by N310toN170

If shot from an AR, brass needs to be completely full length sized every time at the increased risk of failure to feed correctly, stuck cases and at worst...slam fire.

Neck sizing only applies to bolt actions.

As for trim length...the subs don't need it as often because of case stretch but are much more sensitive to neck tension variances, so I trim to 1.355" every time but especially if using a Lee Factory Crimp die. Changes in length directly effect neck tension when the FCD's are used.

Your primers look like they are flattening but the test will be how they feel trying to press in a new primer after sizing. If they are loose, then your pressures are definitely too high.

Lastly...I'm assuming you have an adjustable gas block to lessen the pressure of shooting hyper-sonic through a pistol length gas system?

I do, but I also was having issues with this as no matter the load, or adjustment, I was not getting lock back on an empty mag and was having periodic cycling issues, I have a thread on this in the other 300 category (rifles and pistols)on this web board. I am having the gas port up sized to .125 and gas block realigned again.