John Taffin has data for a 385 LBT in 50AE clocking 1,325-1,450 in a 7.5 FA 83. He claims to have loads in the 83 with the same bullet at close to 1,600. I'd bet the case would run a 400-440 in the 1,200 area in a BFR 50 AE with nose foreward without too much powder gymnastics above SAAMI.
Can't imagine the 50AE doing the same at less pressure than a 480 Ruger with same weight bullets, since a BFR/Freedom 83 have been platforms that house much more aggressive cartridges, bore and pressure wise and both cases are the same length.
Its like the boring but true comparison of 44 Mag to 45 Colt, in this case the bore increase being a bit more substantial and pressure range less.
The non custom 5.5 JRH barrel IS a big plus, but a 6.5 isn't out of line.
Maybe the 50 AE is a crimp jumping liability, but I didnt see any indication of anyone using a cannelured (cast) bullet conjoined with mentioning a roll crimp, profile crimp or LEE FCD, despite the fact the taper crimp was (fairly recently) historically a product of consistent feeding in autos with smooth sided jacketed bullets and cast wadcutters, NOT as a solution to lacking headspace.....yes, auto reloading dies for decades were ROLL crimp dies. Ross Seyfried's own championship 45 ACP loads specified a "slight ROLL crimp".
A tight fitting bullet to the throat also helps eliminate any headspace issue, again something a deep seated (auto magazine length), undersized jacketed bullet is more succeptable to in a wheelgun, but rarely encountered.
"Case mouth" headspacing is so dire 90% of 45 ACP reloaders trim cases about as often as the Pope picks up a hooker in broad daylight...
