MGM isn't using one of my reamers, but they did base their throat length off one of my dummy rounds that was sent to them by a friend last July/August.
Unless something has changed, they are using a 25 WSSM reamer to cut the body and a .358 neck reamer and throater. Nothing wrong with that in the least, other than maybe some minor variation in throat length between barrels.
They've generally been throating them on the long side, which is good - more throat = more room for powder. A good friend has one, he can seat the 225 Nosler out to a little better than 2.425", as I recall.
In that setup, it really maximizes the 57g of water capacity the cartridge has (incidentally that's exactly the same as a 358 Winchester).
No problem in using the preformed brass and dies.
The 358 Grant uses shortened and necked down WSM brass with an "improved" shoulder, its a great cartridge as well - but a little more work in my opinion.
Unless something has changed, they are using a 25 WSSM reamer to cut the body and a .358 neck reamer and throater. Nothing wrong with that in the least, other than maybe some minor variation in throat length between barrels.
They've generally been throating them on the long side, which is good - more throat = more room for powder. A good friend has one, he can seat the 225 Nosler out to a little better than 2.425", as I recall.
In that setup, it really maximizes the 57g of water capacity the cartridge has (incidentally that's exactly the same as a 358 Winchester).
No problem in using the preformed brass and dies.
The 358 Grant uses shortened and necked down WSM brass with an "improved" shoulder, its a great cartridge as well - but a little more work in my opinion.