Purpose difficulty: Around the 3rd round I get a light hammer strike. I have experimented with each H2 and H3 buffer weights. H2 I used to be only having a single shot, H3 I now get two photographs off. I have tried using this on two uppers, just one carbine https://manueliapfu.scrappingwiki.com/1741697/the_rarebreed_triggers_diaries