500grains

I've said it before in response to
"I see the primary advantage of the .500 AHR being that it does not have a rebated rim,
so it is a lot easier to get to feed reliably than the .500 Jeff."

The only reason that Custom 500 Jeff's didn't feed is because the Gunsmiths
who built the guns didn't bother to work out how to get them feeding correctly.

It's got nothing to do with the Cartridge.

I know of about 6 - 8 guns here that all feed 100% reliably including mine.
Some are built on M98's, the odd one on Brno's.

500 Nitro