Short Magnum rounds present their own issues for T\C frames. It's not just the pressure the full house rounds produce but also the cross-sectional area of the cartridge. Combined, these produce a certain amount of thrust on the breech, which is almost all taken up by the locking bolts and the barrel lug/hingepin connection. That's why you can shoot .223's in the Contender @ 50,000+psi, but the .444 based rounds need to be held to under 45,000, and the 30/30 based rounds under about 47,000 - 48,000.
Short mags - fat cases - high pressures - too much thrust= Frames that grow. Not a good thing.
Dave.