Glock has a reputation for being a safe, reliable and pervasive fire arm. I purchased a Glock Model 19 9 MM and discovered a characteristic that I found concerning. With in my first 100 rounds I had one jam and one failure to feed. I discussed this issue and was told by the dealer that the issue was my hand grip. He explained that the Glock needs to be held with a stiff wrist to provide blockage so the slide will be forced fully to the rear to complete the ejection and reload cycle. I changed my firing stance to place my left hand on my right wrist and the problem has not recurred. I have had more than one dealer tell me about this so I assume this is true. I have never encountered this issue with a Colt 1911 or my wife Walther PPK .380. On the range a failure to feed or jam is an inconvenience. In a gun fight it might make the difference between coming in first or second. Coming in second in a gun fight it not a good thing.