Welcome to the forum, Guy! A lot of H&R owners think the screws are too long, but usually the culprit is thread locker in the threads that prevent the screws from tightening. On over 30 barrels, I have yet to find a barrel that didn't have a bunch of thread locker residue in the bottom of the holes. The holes should have shiny bottoms, if it's dull, it's still plugged up.
Dodd3 fitted his FP sight with thumbs screws to eliminate the need for a screwdriver to make adjustments. I'll se if I can find his post on it.
Tim