A cartridge that has been fired in a "fat chamber" can be squeezed back down but their will be an excessive working of the brass. The problem increases when the cartridge is a belted cartridge. The belt will swell and cannot be sized back down. I cracked two quality bushing dies because of the swelled belt. In non belted cartridge, one could just neck size but that is just covering the real problem. The real problem is a bad chamber, and having a die made to fit that bad chamber is not the route to go. Get a new chamber that will fit regular dies. Been there and done that. Just my 2 cents, or maybe 3.