MKII Target Rear Sight

[Highstandardguy]

I'm refurbishing a SS MKII (1985 vintage) and needed to get the target rear sight off. BIG PROBLEM. It required a large brass punch and a large hammer to get it off. What I found was the metal on the dovetails was seriously distended. The base was clearly too large for the receiver slot. I'm not sure how they ever got in on in the first place. I ordered a new base from Ruger and was able to get it about a 1/3 of the way on. When I removed it, it was doing the same thing.

I had a sight off another SS MKII (1986 vintage) that had been replaced a number of years ago. It showed only normal scuffing of the bluing but no distended metal. It tapped right on with I would consider a normal amount of force. I called Ruger and explained what was going on. They assured me that nothing had ever changed with the spec for the sight base even though I had a clear example of a difference. They did offer to install the base if I would send them the gun.

Anyone encounter a problem like this?

 

[rugerguy]

only when someone tried to put an adjustable rear sight in the rear of a 'standard' auto and tried to "hand cut" the dovetail , to make it oversized enough to 'fit"......the use of a dovetail file, "safe" on two sides of the triangle, and you can touch it up enough to make the original sight go in a bit further....hope you unloosened the smalll "set screw" that is located in the sight body,off to the side and in front of the elevation screw..........makes things really tough to remove...............
never know what some guys can and will do to the 'dovetail' slot , to try and modify it to make the sight "stay in place"......... :roll:

 

[Highstandardguy]

rugerguy,

Thanks for the response. This is a KMK-10, not a 'standard'. I'm not clear how filing the receiver slot would make it smaller. As I indicated, the old target sight from my 1986 KMK-512 (which I bought new) fits perfectly, but the new ones are too big for the slot.

Since an 'original' sight fits fine I'm reluctant to file the receiver to match a new sight. I'm just confused why Ruger insists there has been no change when I can clearly see there is a difference.

I called Ruger records to verfy this was in fact originally a KMK-10 which they verified. Shipped 6/85.

HSG

 

[Pinecone]

Highstandardguy, Understand that when guns get machined at the factory, they don't put on a "new" milling cutter for each gun. You would be paying a lot more for those guns if they did! Chances are, the dovetail cutter used on your gun was getting pretty well "worn", that being the reason for your smaller slot. As rugerguy stated, it's real easy to open that dovetail slot with a "dovetail" file. Just a stroke or two on both sides then try the sight. I have done that on many a gun over the past 44 years. Try to get the slot where the sight needs to be tapped in with a neoprene punch just moderately and your good to go!.................Dick :idea:

 

[Highstandardguy]

I hear what you're saying Pinecone, but if the problem was the milling in the receiver, why does the sight off my other gun fit it just fine. These guns were manfactured roughly a year apart.

The only way one sight will fit and another one won't is that they have to be different. Does that not make sense?

 

[Pinecone]

Highstandardguy, I see no reason for Ruger to give you erroneous info on their manufacturing of sight dovetails. As I mentioned above about "dovetails", the same holds true for "sights"! Sights are mass produced and you can measure a half dozen of the same kind/type and come up with 6 different measurements within .0005 to .004 thousandths. I discovered this many years ago to my "surprise" also. Just the nature of manufacturing so fortunately dovetail files with two safe sides are made to take care of adjustments. Years ago I made my own. You can get these from Brownell's. The 60 degree file is for standard slots and the 65 degree for the some newer style sights. My suggestion would be to "decide" one way or another which sight you want to use and make the necessary adjustments for "that" sight! It is "not" a good idea to keep changing sights as that dovetail "will" eventually "open" up to where the sight will be too loose and you will have to take other corrective action such as a set screw or tightening the dovetail itself through various methods...............................Dick :wink:

 

[rugerguy]

yes, besides, if you "repair" ( fit) for the "new" sight provided, thats the sight for the gun from now on, no need to be swapping them back and forth, once on, they should be there for the duration...as said, there can and will be variations ( plus & minus) for production ( or vendor/maker variation), and the NEW parts, being NEVER on a gun, can be over sized and just "maybe" need to fit the angles of the sight body itself, we have done it BOTH ways over the years, but as to what you said the old dovetail was "boogered" or such, and we were just trying to get the dovetail, back up and in place ( proper looking and fitting) as I said in my origianal post we have seen guys do more harm and damage trying to tap down the metal, punch metal one way or another, to try and make the 'repair" so without seeing just what needs to be "fitted" and by "how much" needs to be done to one or the other( the dovetail or the sight body itself on the "new one"........) hard to tell or "see" it without the gun in front of us or at least a GOOD picture...........
I would be willing to bet that there may be an oversized ( wider) sight body available for just this case where the dovetail may have become "oversized"???????nothing surprises us anymore....look how many years it took for Colt 1911s to have available, an "oversized" stock bushing from all the guys stripping them out over the years.......... :roll:

 

[Highstandardguy]

For some reason I don't seem to be able to make myself clear on this issue. I'll try one last time.

1. The slot in the receiver is not oversize, it's too small for the currently available sight bodies. I can see no evidence that it is in any way damaged or modified.

2.The sight that came with the gun was so tight that I had to use a large punch and hammer to get it out after striping it down to just the base. I don't know how they got it in there in the first place. When I tried to install a new sight base from Ruger, it was too large for the receiver slot as well.

3. I tried a sight that had been removed a number of years ago from a similar vintage pistol and it fits perfectly. I bought the gun that it came off of new so I know that the sight had not been modified in any way. It has some minor imperfections but I'm going to live with it because it fits and the current run of Ruger sights don't.

4. At one time Ruger did make sights that fit my pistol. I have two of them, the one that's on this pistol and the one that replaced it on my other pistol.

 

[flatgate]

It seems to me you just need to adjust the size of the rear sight to fit your gun's dovetail.

Sights are cheap.

JMHO,

flatgate

 

[rugerguy]

thats what we said...........???? I used the word "boogered", for YOUR word "distended"..........
as we said above, possibly the new sight being "brand new, NEVER in a gun previously, thus NOT fitted..." would need to be, to install it, either modify the sight 'body' dovetail angle, OR run a file (a 'safe" dovtail file) in the existing dovetail, located on the top of the guns receiver....sorry , but I can't get any "simpler" than that...............

when you put an "older sight", that has already been fitted for another gun, it should go in rather easy, the "distending" has already taken place :wink: