Took some fire power to the range this week and one gun that I fired was my Colt Defender. I have fired this gun before without incident, but it was kickin shell caseings back at me. One hit my head and blood trickled down. What's wrong with this thing? Any ideas? Going to gun show in Atlanta this weekend and this one may go on the auction block. It's and otherwise great gun, has Crimson Trace laser grips, but I was crimson traced by it.