Operate problem:  Within the third round I get a light-weight hammer strike.  I have experimented with both equally H2 and H3 buffer weights.  H2 I had been only finding one shot, H3 I now get two photographs off.  I have tried out this on two uppers, a single carbine and 1 pistol, but utilizing the exact BCG.  I ordered an aimsurplus NiB BCG,