[kwg020]

Installed 1911 recoil bushing on the back end. Gundoc's medium gas block bushing. Shooting medium hot loads (24 gr. IMR 4895 CCI primers and Sierra 65 gr. Gamekings).
At end of the magazine last round, the bolt failed to lock back on numerous occasions.
Any advice?

I have found 24 grains of 4895 to be a minimum round. With 55's and 60's in my Mini's they are hit and miss locking the bolt back. The good thing is only .2 more of a grain seems to be the fix. I doubt the 1911 bushing at the receiver end is a real problem but you can take it out to elimiate a variable.

Also keep in mind 4895 does not meter as well as ball powder. You may be getting some loads lighter than others. I like AA2230 and 2460 in my Mini's. kwg