It wasn't the frames that cracked, it was the barrel at the bottom rear, where it is clearanced for the cylinder gas ring. Some .44's did this as well. Hasn't been a problem for a few years. But the cylinder walls on the .45 are very thin, especially at the bolt notches so shooting mild loads is definitely recommended regardless of cartridge case (45 Colt, 45 Shofield, 45 Cowboy Special)