I have shot about a thousand rounds through my xd-40. I usually shoot UMC, I've had about ten of those malfunction FTF. Then, the other day, I had to take my gun to GanderMt. and have their gunsmith teach me how to "fix" the newest problem. I had just oiled it up because it was starting to rust (hadn't shot it about three weeks) and went to put it back together. The feed ramp jammed under the foreward guide rail. The gunsmith said he had seen it before with free floating barrels. Will it do this when I need it to fire too? Also, what's a better amo than UMC?