I have a set of Tech-Sights on order. I spoke to Larry over there, and he didn't indicate any backlog at the moment. I expect them to arrive within a week after I order them.
But even when they arrive, I'll still be looking for a more precise target-style peep / aperture / diopter sight set-up. I don't know of any good rear sight made for real rifles that would just bolt-on to a 10/22. They seem to involve drilling and tapping your receiver, if your gun wasn't originally made for a specific rear sight. The bolt-on sights by Tech-Sights, Zephyr, and Williams seem a little too casual. They're field sights, not target sights.
I do know of a good rear peep / aperture / diopter sight that is made for AIR RIFLES, $300- $400 airguns that teens and adults compete with and train to become real marksmen with. An airgun supplier has these sights for sale. But now the challenge is to find a front sight of the correct height and style to work. It has to easily attach to the rifle, but it also has to be tall enough to line up correctly with the rear peep. I'll see if the supplier of the rear peep can help me locate the right kind of front sight, and maybe I can talk him into stocking it as a regular item.
If you find out anything, let me know. I'll do the same and post the results here, if not in this specific thread maybe in another thread about Ruger 10/22 aperture sights here at FirearmsTalk.com
Tech Sights came in and I put them on my standard factory Ruger 10/22 with the skinny 18" barrel.
I easily zeroed the rifle in at 25 yards, and it was quite a bit more accurate with these sights than the standard factory sights. I felt that the Tech-Sights were more comfortable to use, too, since they sit up a little higher. I hate having to crush my cheek against the stock to get my right eye down low enough to see the factory 10/22 sights.
But I could not zero the Tech-Sights at 100 yards. I was hitting low. The rear sight unit was not adjustable for elevation. (It's only adjustable for windage, and easily adjustable with that handy-dandy AR-15 /M16 tool).
I screwed the front sight down as far as it would go, but it didn't go down far enough to get me in the black at 100 yards. Even with high velocity ammo I was hitting 8" low. So I will either take a file and shorten the front sight pin, or I will cut a spacer out of leather or rubber and install that spacer under the Tech-Sight rear sight, to lift it up a bit. (But that may require extra-long screws-- tiny little screws only about 3 mm wide and having 40 threads-per-inch.)
Oh, I know the original poster was looking for a rugged field/ military type peep sight, but I just wanted to toss this out:
I got an Industry brand match-quality rear aperture sight. It's click-adjustable, has a .040 aperture, a soft rubber eye cup or shade, etc. It looks like a $200 unit, but it only costs $69 from Archer Airguns. It will mount to a tip-off scope base about .42-.44, such as the Weaver T-09 scope base ($8 available many places).
On a factory tapered 10/22 barrel, the only front sight that is tall enough to work is the Tech-Sight front sight unit, with the M16 type front post turned to a high setting-- about as high as the tops of the protective "ears" on either side of it. That will put it about 1.25 inches above the center of the bore, which will work well with the tall air rifle rear aperture sight.
On a Ruger 10/22 with a .920 bull or heavy barrel, it looks like the best thing to do is get a Tech-Sight dovetail adapter, and then order a Lyman globe-style front aperture sight with interchangeable inserts. The front sight needs to be about .87 tall, and Lyman makes one that's .85, which should work.
Here are pics of my 10/22 with an A.T. "fiberforce" Dragunov-style stock and the Industry brand rear sight from Archer Airguns and the Tech-sight front sight unit.