I use an RCBS 45-300 FN. I have one cavity hollow pointed the other is a FN, both GC. The 45-90 originally used the 300 gr. bullet as to get higher vel. I would think that up to 2100+ would be doable, remember a 405 Win. is 2150 full blast w/a 300 gr. Pretty sure that the cast GC bullets can be pushed as fast as any jacketed.-Muddy
