Check with Ace or other hardware stores for allen head set screws of the proper thread size. They come in different lengths that should fit your needs.

 

The screws used to mount those Ruger rails or to fill the empty holes are most likely #6-48 or possibly #8-40.

Neither threading is going to be available at your local hardware store. You will have to find them at a gun shop, gunsmith or a specialty industrial fastener.

 

I took the top rail off my Mark IV 22/45 Lite and installed an Outer Impact M.R.A. adapter for a Burris Fast Fire II which left one exposed threaded hole on the top of the barrel shroud just in front of the adapter plate. I called Ruger (Phoenix Arizona) customer service and spoke with a very nice lady named 'Beth'. I explained it to her and she asked whether my barrel shroud was stainless or blued? (that was the only two options that Ruger had). I told her blued (I can touch it up later to matte black). She asked for my name and address and said that a few 'filler screws' will be in the mail the following day. That was two days ago so I should be getting them in he mail early next week. Call Ruger and they will take care of you. Great customer service! :bthumb:

 

Um, Ace Hardware has a selection of gun screws. It's not a great selection but you can find the screws for what the OP wants to do there. Since I only wanted one the manager gave it to me. Because of that nice gesture I've purchased a few things there since.

 

Howdy,

I did (almost) exactly what you did... I bought my Mark IV Tactical, and removed all of the rails. I bought a Burris FastFire III red dot (with special base for the Mark IV) and wanted to fill all those open holes on the top and bottom of the barrel.

The easiest way to do this is to simply go to eBay and search for something like "RUGER MK I II III IV SCOPE BASE FILLER SCREWS" and find the most suitable combination of screws and shipping for your needs.

For me, I think I found two packages of three screws for $15 shipped. That was a great convenience. The screws were a perfect fit.

I hope this helps.

kourt

 

That's great! I took the cheap way out and emailed RUGER. Once I certified i was a U.S. citizen (really), Ruger said it would send me what I need.

 

Ruger sent me a few upon request (no charge). I got them yesterday.