Thank you for the detailed reply.Haven't stress relieved the cases yet...they have been fired 5 times at this point. After f-forming, the f.l. bushing die is adjusted to push the shoulders back .002 (measured from a fired case with primer removed). Chamber neck is .256 and the necks measure .253 across the base of the bullet. Flash holes are equalized with a fairly aggressive chamfer around the inner flash hole. Powders are Rl15 and Benchmark.
If you're lobbing heavies with lighter charges of slower powders, neck sooting may be more of an issue. May not mean anything on target. Or it might.
Good shootin'-Al
I am only bumping .0015 with stripped bolt method. I am getting the sooting on shoulder after 3rd firing, after the 2nd it was neck/shoulder junction.
I was getting the sooting shooting a long 55gr copper bullet with n150 - would call it a high pressure load as was at 3800fps
Also shooting 88eld with a heavy load of n160 as a compressed charge.
I assume you are shooting light bullets with the use of benchmark & RL15?
Sooting is causing an issue on target also with a heavy bolt on the worst sooting offenders.
The chamber neck needs cleaning to get the gun back on ‘ zero ‘
