[Milsurplus] set screw question -

[Tony Snider]

method that works for me EVERY time on old Mil gear

soak them good,

use a good made in USA straight shaft Allen with a nice fresh cut/new end
(like an Xcelite set )

 use a small adjustable wrench to put a little pressure the way you want to
turn the set screw,

 give the butt of the Allen shaft a few taps with a little brass hammer,
jewelers version of an impact gun!!  gets even the super rusty ones.

the shorter the shaft better it works. It was worth it to me to buy a set
and cut them down.