I have a glock 19 gen 3 and a 17 gen 4 today was shooting the g 17 now at around 600 rounds on the first shot today got a jam the first one using brazer brass fmj 115 the spent cartrige flipped was backwards poped the clip racked it and was back in business the week befor I had just cleaned it & this was the. First shot could it be the oiling ? I went on a nother 50 rounds worked great. Could it be something I did?