First, how many screws and cross slots are in your base? Sounds like you may have an Ultra base that they put on the varmint rifles. This base has three mounting screws in the rear and a standoff screw on the front with set screws on each side for the contoured barrels to strengthen the cantilever. This base is 6 inches long and has 6 cross slots, the standard base is 5 inches long and has 5 cross slots.
Is your USH a 12ga? Maybe they put the Ultra base on the 12ga since it is actually a 10ga blank. My 20ga USH has the standard base and it makes full contact over it's entire length.
Its hard to say whether you bent your base or not, but you could lay a straight edge such as a metal ruler or something lengthwise on top and check for any gap in the middle.
If that screw has set screws on each side of the base, then you have an Ultra base, that screw is just a standoff screw and there is no hole in the barrel. The three screws in the back of the base are the mounting screws. Hope that helps.