Just bought a new BG .380. I understand weapons need some break in time but I am concerned with the performance. Out of 50 rounds, had about 6 FTF and the slide fails to lock after last round is spent. I was using some factory reloads as that is all the shop had at the time. I will try some Federal as that is what the first spent round that came with the weapon was. The slide will lock with an empty mag, just not after the last round for some reason. Any suggestions before I send back to S&W? I love my M&P shield 9mm but this BG is something else!