Abstract: A semi-automatic firing carbine anti-jamming cartridge loading system is provided wherein no feed lips or a portion of said feed lips are removed, wherein the cartridge to be loaded is fed to the carbine breech along a feed ramp. A bolt enclosing the firing pin includes a pivot plate mounted on the bolt nose, rotating about an axle. A recess formed in the bolt nose provides spacing for the pivot plate to rotate about said axle. If the firing pin protrudes through an aperture formed in the pivot plate, while the pivot plate is still in its collapsed state, then the weapon will jam by the firing pin hanging on the top part of a rim portion of the next loading round, thereby thwarting attempts at reconfiguring the weapon, that employs my novel system, to be re-converted as a fully-automatic weapon.