SAAMI specs call for a maximum of 40,000 CUP or 36,000 PSI for the 44 Magnum. Do not exceed these limits. I don't care if it is a Redhawk, Super Redhawk, Super Blackhawk, or lever action carbine. These limits are not always the limits of the gun, but are limits of the brass. Exceeding the maximums will eventually get you hurt.