[Kalos]

Sorry if this's ever been posted on before--the search seems to be 'disabled by the administrator' at the moment. During a trip to the range today I noticed that the rear sight on my Ruger Mk II seemed... well, a bit off center. It'd been a while since I'd shot this particular pistol, so I shrugged it off and did my shooting; as I was at 25 yards, I was just happy to be on the paper, and didn't notice any particular accuracy problems. When I got it home and was oiling it down, though, I discovered that I could push the whole rear sight assembly back and forth in the dovetail a good 1/4" or so either way. :P What's the fix for this? It's an adjustable sight model, so I just need to get it generally in the right spot and then I can zero it back in.

[jeff-10]

I always have the opposite problem, my front side is always loose. Even manages to wear lose after i loctite it.

[Kruzr]

It's not uncommon on Mark 2's with adjustable sights. Loosen the set screw and drift or push it out the right (starboard) side. Degrease the area under the sight and the bottom of the sight with alcohol or brake cleaner. Take some blue loctite and spread a little near the left hand edge (when looking from the back) of the bottom of the sight. Drift the sight back to the middle. Put a small drop of blue loctite on the set screw and tighten it down. Let it sit overnight.

If you want to avoid the loctite, then degrease as above and use a punch to put a dimple in the bottom of the sight. Just raise a little metal. Then drift it back in and tighten the set screw.

[DougCxx]

You guys should count yourselves lucky; my problem was the opposite. When I decided to try mounting a scope and wanted to remove the rear sight, I found that apparently the factory had cut the dovetail 1/32-inch too short, and then pushed the rear sight block in with a twenty-ton press. There were little curly slivers of metal coming off it where it had peeled back when it was pushed into the receiver.
~