What load are you using to get 2820 fps with the 750 gr A-Max. I have shot alot of 50 BMG rifles with this bullet and in a 32-36" barrel length, all have limited out at around 2700 to 2750 fps with proper pressures for the 50 BMG, that being, being able to rechamber a fired round with no real resistance on the bolt when you close it on the fired case in the chamber.
I have run them over 2900 fps so far with decent results but thats starting to move the brass quite a bit and resizing takes some effort.
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