Yep, overtravel adjustment screw. I don't mind a bit of overtravel, so I have mine adjusted pretty shallowly. For a bullseye shooter they are a must, for general plinking and field use I think they are more smoke and mirrors.

BTW, nice gun, Now I understand the handgun ammunition questions on the handloading board. You'll want to shoot that honey a LOT, and handloads are the only way to go.