So I took the fireformed cases and being anal, I decapped one, put in a new LR primer and fired it "pop".
Then another and sized it in the RCBS die, primed it and "click". No mark on the primer.
Then another and only sized 1/2 the neck, primed it and "pop".
Soooo even with the load I tried (30 gr TAC) the cases are still not fully fireformed. Sizing 1/2 the neck and not touching the body creates a false shoulder to hold the case against the bolt face. Hoping a 2nd firing will fully fireform the cases.
As the intended use is cast light loads, I may have to have NOE make me a takeoff on the old Hudson 32-40 bullet with a bore rider nose, three .312 band and three .315 bands.
Somewhere I have a Lee 160gr mold for the 7.62x54 that drops at .313. will give it a try also.