Solution: Sharply tap the base of the magazine to assure it is properly seated in the gun and then rack the slide. This seats the magazine, clears a defective round and chambers a new one. There is one major caveat to this technique: If you get a "pop" or a "poof" instead of a "click," the primer did not ignite properly and that bullet may be lodged in the barrel as a squib load. Or, if you rack the slide and an empty case comes out, you have the same thing. Do not fire another round! Stop and inspect the bore for any obstruction. Firing into an obstructed bore can result in gun damage, personal injury or both.