I took my 10 out this week and put about 50 rounds through it. It shot perfectly as it always does. However, when I was cleaning it I noticed the cylinder was hard to get open. I really had to pop the backside of the cylinder to get it to come open, and it didn't always open on the first whack. When closed, it turns and functions like it should. It doesn't seem to bind on anything. What is wrong with my poor little 10?