I agree with taking it to a machine shop.
There are two options that I use.
1: Drilling it out on a milling machine with a carbide drill bit.
2: Coating the action ( around the screw) with Heat Stop (sold by brownells) and welding a small bolt (same size as the screw) to the head of the screw, which will allow you to get a hold of the screw to twist it out.
The heat applied by the welding loosens the loctite.
CPT USAR Ret
USAMU Sniper School Oct '78
Distinguished Rifle Badge 1071