I am aware of two different scope mounting systems for your pistol, made by Aimtech and B-Square. Of the two, I have used the Aimtech type on other pistol models (not the 622), and they seem to work well. You do have to use some Loctite or other screw-glue on the grip screws to keep them from coming loose under the stress/vibration of repeated firing, but other than that, I've seen no problems with the Aimtech mounts. Most models allow you to still see/use the iron sights under the mount.
Originally Posted by lbslures1
The B-Square system looks like it would work, but before I'd use it, I'd just take the gun to a gunsmith and have 3-4 holes drilled and tapped in the 622's top rib, and a Weaver-style base screwed on. The cost would be similar, but the mount would be a LOT stronger, and lower, too (many folks like the lowest possible mount for pistol optics). This type of system would block use of the iron sights, but I'd accept that trade-off for the strength/simplicity.
Links to the two different mount systems (I've not dealt with these companies, so I am not endorsing them, just using them to illustrate the options):
AIM APM11 MNT SW 422/622/2206 BLK
B-Square .22 Semi-Auto Pistol Mounts
"Placement is power" -- seen in an article by Stephen A. Camp
(RIP, Mr. Camp; you will be remembered, and missed)