hey john! i've been following your post closely, and have start my own underhammer build, also. starting with a solid block of aluminum, i'm at the point where the hammer and trigger have been installed in the roughly machined reciever block, but i feel like the half cock notch is interfering with normal operation. do you normally need to "tune" the operation of these parts? (by the way, you have succeeded in impressing me very, very much)