T/C custom shop lists 38-55 as an available caliber in pistol and carbine bull barrels. I didn't ask, but suspect they will have the faster 1-12 twist of the 375 winchester and not the traditional 1-16 or 1-18 twist of the 38-55. If you are only shooting jacketed bullets, probably not an issue, if you are going to shoot lead it's not optimal.
regards,
Graycg