Putting a new scope on my Ruger #1 and found one screw not seating about half way down. I did not force it. Is running a 6-40 die to clean up the way to go? Before I buy something, is there a fine or coarse die to choose from? Thanks, Bob

If the screw is buggered just get some new ones from Ruger or Brownells. Might also need to clean up the hole with a tap.

1: First determine if it is the screw or the hole. It's probably the hole.
2: If it is the screw, get another one.
3. If it is the hole, try running a TAP. (not a die) into it, but that probably won't work. Ruger scope ring screws are size 6-40. I would just go too step 4.
4. Re tap to an oversize 6-48 screw, which Brtownells sells taps and screws for just this purpose.

Ah, thanks, It's the hole. First I should try a good clean with carb cleaner to see if that works. Hard to believe I cross threaded it long ago. DPCD, thanks for clarification, it's a tap, I'll remember.

Note. Ruger actions can be hard as woodpecker lips... retapping could be a few minutes of tense work

Jeff, thanks. It's the scope ring hole, not the action. Will update once I clean thoroughly. Will also get new Ruger torx screws.

If the screw is catching 3 or more threads, you could shorten the screw.

Be very careful to not put any side force on the tap.

Taps are every brittle, and you do not want to snap one off in the hole.

Use a little juice and a 6/40 in a Ruger hole, works or me, Ruger screws are 6/40 and it never hurts to cut all holes to a 8/40 on big bore rifles if your handy....