I have a Ruger M77 Hawkeye All-Weather that I haven't gotten around to setting up. (Before I spent too much time here at P-F, I used to spend too much time over at 24HourCampfire.) I decided to check out the rings awhile ago, and found one of the screws had damaged threads when I removed it. Got another ring, went with a low so I could mount the scope a little lower, rather than just replacing the high one that was damaged. Well, the replacement also had damaged threads on one of the screws when I removed them. Some of the other screws felt a little gritty, as if the problem was blast media left in the threads when the screws were installed. (The rings are matte stainless.)
I procured new Ruger scope ring screws and a #6-40 tap to chase the threads. Both items were delivered today, so I proceeded to chase threads this evening. Which gave me time to handle and inspect everything a bit more closely. On one side of two of the rings, both thread sets were angled relative to the holes, so they started out uniform at entry, but by the bottom, one side of the hole had really deep threads and the other side had really shallow threads. And the tap that followed the existing threads was obviously not perpendicular to the machined surface that faces the machined surface on the top strap.
The worst thing, though, is that I realized the inside saddle surfaces, at least on the top straps of the rings, appear to be as-cast, with very significant casting flaws on the surface that bears against the scope tube. I had initially thought these surfaces were just grit blasted to "matte" them after machining, but no machining process could leave the defects present on the parts I have here. These defects could/would cause serious damage to a scope tube if the rings were tightened, which would almost certainly not be handled by a scope warranty (with the possible exception of Leupold's).
On the basis of these parts, and assuming they are representative due to the uniformity of their condition, my opinion is that Ruger factory scope rings should not be used without serious rework. At a minimum, correcting the flaws to make the rings serviceable would require filing or stoning the lumps down, then heavy lapping or even reaming the rings to ensure they are straight, round and smooth so the scope will not be damaged.
It would probably be cheaper and easier, and likely yield a better result, to just buy quality rings from another supplier, such as Leupold, and drop the factory rings in your recycle bin.
I believe the rings are essentially the same for the big revolvers, so this would apply to those parts as well.