While I would not recommend it I can tell you that 72grs of Retumbo gets just shy of 3250 fps in my long throated chamber and a 26 inch barrel. 1800 rnds and still accurate.
I have shot this load in factory Remington .264 Win Mag chambers and have worn out them out in 1200 rnds. It is way over book loads and almost assuredly way over SAAMI max pressures. I am not saying it is a safe load, only that I have shot quite a few of them and never died.
I believe the throat geometry has more to do with the short barrel life than the high pressures.
John Burns
I have all the sources. They can't stop the signal.
