The 4 molds I have for my Blackout AR are - 311365 PB, 311291 GC, Lee 312-155 GC, 311413 GC.
I've casted and sized to .310 A LOT of these boolits. Plan was to use them for blackout and an M1A.
I made some dummy rounds for the blackout just now and struggled to get any to cycle. My manual lists COAL for all at 2.000 and above. There's no way that's happening. I was able to get a 311365 to chamber and eject at around 1.980". These fit and drop from a Sheridan gauge.
I'm using a Lee Taper Crimp.
Any ideas what could be the problem? Do I have to load these deeper? What about taper crimping? I run the bullet up in the ram and turn the crimp die until it stops, lower ram and then add a quarter turn.
Maybe size them to .309? I'd have to order a new sizer as I polished mine out to .310.
The 311291 did not chamber from the mag well either, it was awfully short. I think it's a good round for the M1A.