I personally prefer weight in the barrels balancing ahead of the knuckle for more accurate offhand shooting, while others want the rifle to balance at the knuckle or just behind, on the water table.

I'll see what I can find on the various .45 ctgs. as per pressures at velocities. I know that older Lyman 300gr. from the 3 1/4" was in the 2,200fps to 2,400fps range, at what was hinted at, as being 35,000psi. They declared it OK for the modern made Sharps, however I'd not shoot that load in a big firing pin rifle without VERY carefully working towards it.