Wow a .50 that is a BigBoy. ...
Are you talking about , You may have to Neck-Turn the Brass ?
You might not have to do any Neck turning if you got the room. Sounds like about the same as sizing other brass. You can quickly check If you got access to the Reamer used to cut the Chamber ???. You can Mic. the Reamer Neck to see what the cut is. Then do-up a brass with a bullet in. To then Mic. the OD of the cartridge Neck and see how much expansion tolerance you got going on.
also, You can do a Sulfur Cast of the cut Chamber you got to see what the dimention is. Then Mic. the Brass with a round in check also.
I am in No Way an authority of the .50 platform and don't know what tolerance you need in the Chamber area for expansion/contraction of the brass neck. Normally I like to have at least few thousands but the BigBoy .50 might need Way more, Or maybe not ?. So you might want to find out from a person that is (in the Know) what a good # is for space for starters.
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