quote MedRiver: "Am I understanding that you are shooting the cast at the .413 diameter or resizing down to .410 or .411 from .413?"

Cast bullets work best for accuracy and non-leading if they are +.002" (greater) in diameter than the rifle barrel groove diameter.
Jacketed bullets and monometals work best at groove diameter or maybe even - .002" (lesser) than groove diameter.
Certainly a .410" diameter jacketed or monometal bullet will do very well in a .411"-grooved barrel.


"I have never resized before. Does it strip the gas check in the process?"

No. The gas check is actually applied and crimped into place as the cast lead bullet is sized by a base-pusher sizing die,
like LEE or CH4D. Very simple and easy. Even a caveman can do it.


"Will new properly sized gas checks be needed?"

Maybe, depending on the mould.
The Hornady .416-caliber gas check may do.
I got some .41-caliber gas checks from Bullet Swaging Supply, Inc. in Louisianna.
I use those on my .397" cast bullets for my .395-caliber wildcats.
I do not have a 41-400C mould form Accurate Molds ... yet.


"Also, for those looking to order QC brass, I just tried to order 5 bags (100 total from Grafs). At checkout they only had four so guessing now they have none.
May be worth a call to QC to let them know there is some demand. I plan to call tomorrow myself."

That is good to know.


Ron aka "Rip" for Riflecrank Internationale Permanente
NRA Life Benefactor and Beneficiary
.458 Winchester Magnum, Magnanimous in Victory
THE WALKING DEAD does so remind me of Democrap voters. Donkeypox.