Help in removing front trigger guard screw on my enfield no.4 mk1*

[flying pig]

Is the slot on the screw head toast? If the screw is shot you can use an easy out but on small fasteners like on a rifle it takes a lot of care to not cause a disaster in the drilling stage or actual removal. I've only ever used one once on a rifle and it definitely was a last resort. Also I have saved old screwdriver shanks and blades to use to give the screw a light tap on the head utilizing the slot to help break any corrosion up that may be binding the threads. Die grinders and heat I'd say would be two terribly bad ideas! Maybe penetrating oil could help?

[Patrick Chadwick]

If you've the padded vise jaws and a drill press, place a bit in the chuck , bear down on the screw and use either a strap wrench or some other torque multipler to attempt to turn the screw whilst it's secured. (Power disconnected to the press, please!) Generally best done with two people.

This is the best suggestion, if you can arrange the setup. A screwdriver slipping out of a slot will gouge the rifle, and maybe you as well.
There is one method not yet posted, and it has sometimes worked for me. After squirting a couple of drops (you don't want to soak the woodwork) of GOOD penetrating oil around the screw head, and having had the self control to leave it overnight, or at least while you make a cup of tea, try TIGHTENING the screw. Just a couple of degrees can be enough to break the friction. Even if you can hardly see the movement, tightening/loosening/tightening/loosening... can slowly "rock" the screw loose.

As to staked screws - the setup proposed by jmoore is capable of removing staked screws (it did on my M1917) if the screwdriver bit is a really good fit. Since when I know that staked screws are not a 100% guarantee that the rifle has never been dismantled.