Not a lot of if to it - be willing to bet there's a lot of handbuilt ought-six ammo used regularly that's easily 53K CUP. All it takes is a max safe load in the winter shot in +20 deg weather. You're talking 6% increase here - you can do that with .5 grs of powder, a primer switch, ammo left on the dash to heat it up, mixed brass, lots of things. Lots of people reload without using a chronograph and 100 fps ES equals easily over 6% pressure swings.
|