hossdaniels,
This usually happens when a "buggered" up allen wrench is used in the first place.
I would carefully set up the rings in a drill press or Bridgeport type mill, drill out and re-tap.
Depending on the size of the screws, the EZ-OUT method can be tried.
In any case, when you replace the screws. use a new wrench to avoid problems.
Carefull with metric versus U.S. stuff also as some metric sizes are close enough to U.S. as to cause a problem.
Respectfully, Zeke