.22 Mk 3 Target - rear sight walking

[Mk3-2020]

Folks, I am seeing the factory rear sight of my MK3 walking in the dovetail. I drifted it back to a centered point once. After about 150 rounds through the gun the rear sight has again moved to the right. I have attached a photo of the situation.

As I am not a machinist, how is this movement prevented/stopped?

Thanks in advance.

 

[arfmel]

You could remove the rear sight, put it in a vise, and dimple the bottom of the sight with a small center punch and a wee little hammer, then tap it back into the dovetail.

But-I might first try a drop of loc-tite in the dovetail before moving the sight back where it needs to be. Might work, and a lot less trouble, maybe.

 

[Dan in MI]

Some rear sights have an allen screw to lock it down, I 'm assuming yours doesn't. If that is the case look up ^ one post.

 

[Mk3-2020]

You could remove the rear sight, put it in a vise, and dimple the bottom of the sight with a small center punch and a wee little hammer, then tap it back into the dovetail.

Understand where you are coming from. I'll have to investigate Loc-tite grade properties, as again, this is out of my field.
Thx

 

[NikA]

Understand where you are coming from. I'll have to investigate Loc-tite grade properties, as again, this is out of my field.
Thx

Green for bearing install if you have it, but honestly any grade will do. I've even used superglue before.

 

[Mobuck]

As Dan mentioned: tighten the set screw

 

[Johnnu2]

Folks, I am seeing the factory rear sight of my MK3 walking in the dovetail. I drifted it back to a centered point once. After about 150 rounds through the gun the rear sight has again moved to the right. I have attached a photo of the situation.

As I am not a machinist, how is this movement prevented/stopped?

Thanks in advance.

Assuming that there is no set-screw (?) to hold it in place, I've stopped sights that are 'dove-tailed' in place by simply stuffing/wedging a thin piece of (any kind of) metal under the sight and gently banging the sight back in place. If you have an old feeler-guage, you could cut a piece (of the perfect thickness) and use it as a wedge.
J.

 

[Rich/KY]

The Numrich schematic for the MK III shows a set screw for the rear sight base. Might require a bit of disassembly to access it.

 

[sharpblade7777]

My mark 3 has a set screw.

 

[Actnbill]

Red Loc-Tite if the set screw isn't holding it..... I had very good luck in the past with it....

 

[WanderLust]

BEFORE you apply anything, the colors are there for a reason! Blue loctite is a thread locker, but removable with a reasonable amount of force using a standard hex wrench or allen wrench. Red will hold maybe 15% better, but it needs to be heated to about 350 degrees F to remove it!!
Green is a wicking solution, made to be applied to assembled parts. It is much finer/thinner as a result, and may bleed over into unwanted areas unnoticed. It is also very hard to remove once it sets. All of these set up in the absence of air, and will be firm in 1 hour. Best results are waiting 24 hours, but that is an extreme in my experience.

 

[hittman]

Red is for stuff you never intend to take apart

 

[Mk3-2020]

Folks,
Based on your suggestions over these many months the problem has been solved with the use of blue Loctite on both the dovetail and locking screw.

To me, this is solved, and something for future reference to new Ruger users.

Thanks to all.

 

[RC44Mag]

There's also purple loctite which is designed for very small screws, ie. screws like small set screws and scope mounting screws. Either blue or purple is your best bet as mentioned already by some in the know.