 It's got a lot of tolerances built in. And if you're in a mud hole or a rice paddy in Vietnam, you don't want anything gumming everything up. It's not like you're trying to make a 50-yard headshot with this thing. You just want it to go bang when somebody has jumped into your foxhole with you and you're fighting them off that way. If you're doing a custom target gun, you can tighten everything up.