Mitchell, a bunch of Sportster shooters had to send their rifles back to H&R because of failure to fire, the culprit was bad transfer bar timing. Dunno what H&R does to fix it, but they came back working fine.....I haven't tried to figure out how exactly it works other than I know there is a direct relationship with hammer movement and trigger position. Maybe Fred can tell us.... :wink:
The transfer bar is designed to not allow the firing pin to be hit if the trigger isn't pulled.