So I was putting on a clamp mount on a rifle and while tightening the screws, the bit (allen screw) broke off in the screw. There's a 1/10'' sticking out, but not enough for me to pull it. Normally I would take a hammer and a nail and hit it until it comes loose, but the clamp is still attached to a scope. How does one go about removing this? I just want the screw off the clamp so I can get my scope back.