Functionality issue:  Over the third spherical I get a light-weight hammer strike.  I have attempted both H2 and H3 buffer weights.  H2 I was only obtaining one shot, H3 I now get two photographs off.  I've experimented with this on two uppers, a single carbine and 1 pistol, but utilizing the very same BCG.  I requested an aimsurplus NiB BCG,