Drill And Thread For Vertical Adapter

[TheMedievalMan]

Okay, so I have one of those older style rails on my RT ULE. The one with the screw holes on the side, to attach the stamped steel sight rail and front grip mount. But I want my vertical adapter to be mounted directly onto the rail itself. So where can I find a guide that will show me exactly where I am supposed to drill and tap the holes to mount it? Or do I just drill and tap it to the best of my abilities?

[Smoothice]

You just need to drill a hole in the rail. No need to tap it. You may need to counter sink the hole so the head of the bolt sits flush.

[Newt]

You don't need any guide either. Take your VA, align it where you want, and use the tightest transfer punch you can easily fit to mark the rail for drilling. A drill bit will work as well, but it's not ideal. Next, set it on the drill press and put the holes through the marks.

If you've got a good mill, it's helpful to grab actual dimensions, but it's fine in high tolerance instances like this to just use the transfer method.

[TheMedievalMan]

Good idea with the transfer punch. That should give it good tolerances. For the bolt head clearance. I should get a milling bit so that the head of the screw will be flush, right?

You don't need any guide either. Take your VA, align it where you want, and use the tightest transfer punch you can easily fit to mark the rail for drilling. A drill bit will work as well, but it's not ideal. Next, set it on the drill press and put the holes through the marks.

If you've got a good mill, it's helpful to grab actual dimensions, but it's fine in high tolerance instances like this to just use the transfer method.

[Newt]

Yes, unless you're using flathead screws. Drill bit works fine from the top in that case.

[maniacmechanic]

Good idea with the transfer punch. That should give it good tolerances. For the bolt head clearance. I should get a milling bit so that the head of the screw will be flush, right?

it would be nice to have a flat cut " milling bit " for the "countersink" ( clearance for the body ), most all the bolts/screws for these are flatheads ,

[TheMedievalMan]

Yes, I did the drilling and everything. Its almost done, it looks perfect. I will take pictures of it soon. I just need the milling bit, so I can have stainless steel flat head hex screws to fit in flush, from the inside of the rail. I even did it the difficult way, and threaded for 10/32 screws. I did it so carefully to exact tolerances, that it fits perfectly flush. The screw will go in, and thread through the rail, and into the other holes of the vertical ASA. All I need now is the counter sink for the flat head screws.