Thru lug is a better recoil lug (more bearing on the walls of the adjacent hollow square) and what's this stuff about "easier to machine"? What happened to easier to bore out and file by hand. CZapper had the answer in post #2. Who gives a smelly crap about "markers" for best guns? Any such marker badly executed is just froth on some Spanish no-name (bushed pins, breech clips, seven pins).

jack