22/45 rear sight keeps walking loose: any suggestions?

[bczrx]

I love my Mark II 22/45. I hate its' rear sight situation.

I am on my second rear sight [both Ruger-brand thought]. They BOTH will rattle in the notch until the screw is turned to lock it into place. No matter how tight the screw is, they still walk to the left. Both my local gunsmith and myself can't get this to stop.

The last time I 'shimmed' the rear sight up with some aluminum tape on the base and then inserted it and locked it. This held for the longest: 500 rounds before it gradually moved a tad to the left. Normally it would walk severly to the left in 350 rounds.

Keep in mind I do NOT want a scope, as I want this to mimic the sight picture on my other pistols. Thus, I want 'traditional' adjustable sights.

The question I am left with is if my sight groove/notch is too large? If so, do I send it to Ruger and they can weld it up/fix it? Or do they send me a new top end? I REALLY don't want them to send me a Mark III replacement.

What about the Volquartsen rear sight? Is it oversized to be filed down to fit the groove, or is it the same dimensions as the stock Ruger rear sight [which is TOO loose for my pistol]?

Any suggestions would be VERY welcome!

Oh, and my front sight seems to be bent about 2 degrees to the left: is this normal.

 

[Bullseye57]

Use some red LocTite (#271 high strength) on the dovetail slot. You can use some more of the aluminum tape to get a tight fit on the sight base, this will help the locking sealant set-up properly. Since Red is a high strength thread locking sealant, once the bond is made you shouldn't have any more walking issues. Just use a little in the dovetail slot. Do not use it in the sight base's locking screw or you will find it extremely difficult to remove that screw later if necessary. Mark a pencil line on the receiver where you want the base to center and on the sight base itself for a reference point. Put some sealant, a drop is all you need, on the inside of each of the downward sloping edges of the slot and insert the rear sight into the dovetail slot until you align your index marks. Let the sight sit for 24 hours before using and you're done.

I use the Red #271 LocTite all the time on loose Ruger front sight bases.

Hope this helps.

R,
Bullseye

 

[louiethelump]

If the sight "rattles" in the dovetail as you described, I suspect that LocTite will not do it. Sounds like a bad slot to me.............

 

[Mobuck]

One option would be to use a center/prick punch to raise some texture in the bottom of the slot, then use loktite. If you do this, be prepared to verify the sight setting before the loktite cures.

 

[bczrx]

I'll have to give a range update after the next time I'm out. That probably won't be until at least Saturday, if not next week. :(

However, I read a LOT of threads and started to tap the mounting area to rough up the surface. It didn't rough it up enough, and I actually bopped it so hard it dimpled the inside of the slide under the dovetail.


HMMMM.....

I flipped it over and dimpled the inside of the receiver area under the dovetail and was able to 'raise' a good section of the area within the dovetail. It was a PAIN to put the rear sight base back on [with blue loctite, of course]! :D This I take as a GOOD sign, as the sight base didn't want to go in without some FIRM tapping [not slamming, tapping] of the hammer on the side of it [no sight pusher].

After that I felt the inside of the tube that the bolt rides in and it was rough, so I used 200 grit sandpaper to smoothen the edges of the dimples I added to the inside. Once they were smoothened out I then used some metal polish and my felt tip on the dremel to finish smoothing that section. The bolt originally hesitated as it passed that section, but after my sanding and polishing it slides freely and smoothly in and out.

I realize I have to watch for crud build up in the shallows of the receiver/tube thing where I tapped it, but I clean my pistol with the bolt off after every range trip anyway.

After I verify it isn't moving [and I won't trust that until I fire 1000 rounds without it moving!], then I'll consider having the entire barrel refinished, inside and out.

Again, I don't KNOW that I've solved the problem [and no, no pictures were taken to document it], but I think I have, due to how tight the rear dovetail was when I put the sight base back in.

Hopefully I'll have a chance to find out before I am able to pick up my newest toy: I just ordered the SP101 .22lr and will be able to shoot it in about 2 weeks.

Otherwise I forsee an ALL .22, ALL THE TIME range trip in 2 weeks to go through a LOT of .22 ammo.


Thanks for all the tips!