If the KROIL fails to loosen it enough, place a hot soldering iron tip on the screw head for about 30 seconds. Be careful not to touch the plastic. The heat should expand the screw and the "nut" just enough that when they cool the rust weld should be broken. I've done this on many firearms and it always worked.
Terry
Terry

![[-]](https://www.alpharomeo15.org/images/roundo/collapse_collapsed.png)
