Functionality difficulty: On the third spherical I get a lightweight hammer strike. I've tried using both H2 and H3 buffer weights. H2 I was only getting a single shot, H3 I now get two shots off. I have tried this on two uppers, 1 carbine and 1 pistol, but using https://landenndtix.thecomputerwiki.com/5833564/helping_the_others_realize_the_advantages_of_rare_breed_frt_trigger