I have a M1899 US Krag receiver and cut barrel. I am looking to rechamber to 45-70, for low pressure, rimmed cartridge, large bore, and put a 16-20" threaded barrel to shoot suppressed subsonic, 500gr ammo. A real thumper. In theory, if you cut off the rim, created a small channel on the bolt body for the extractor to rotate on that is only if the rim could not be thinned enough to fit the 45-70, tweeked the extractor hook up to accommodate the larger rim, only .0315" higher and lower, as the rim is only .063" larger on 45-70, and kept the magazine box by either shaving down the floor plate and raising the bottom of the action .0315" to fit the rim or alternatively creating a small channel to feed the larger rim as the rim of the 30-40 is still .04" larger than the body of the 45-70. Can anyone fact check this in theory, I have no money into the action, which is in amazing shape btw, so I would be willing to spend some money on making this a unique piece