If you have a spare screw, you can save the breech and destroy the screw instead. You should be able to carefully drill the center of the little Allen head screw with a 1/8" drill bit and when the drill reaches the shank of the screw, the head will pop off. After you get the breech off, grab the screw with a pair of pliers and turn it out. If you need a spare screw, I can post one in the mail to you. Either like the factory one or a slotted one. Let me know.