He chuck on my hammer drill is shot. Took it to the only repair shop I know of and they specialize in Milwaukee and couldn't fix it. I've looked up ways to remove, but this chuck doesn't have a retaining screw inside of it. The key won't tighten the chuck. Me and dad tried to tighten with a vise n pipe wrench but we couldn't tell if we were helping or hurting it. Any experience out there with this?