Scope Stops and Gunsmiths

[lizzie]

I recently acquired a vintage R1 in .20 caliber, and I LOVE the gun! (Thank you Geoffrey!)

As most of us know, air rifles in the "magnum" class are scope killers, and besides being killers, they are also scope migratory enablers- haha.

This gun has the capability of being a One-Ragged-Hole classic, as I can tell, having only had it for a week tomorrow, and most of that time, having been out of town for the fun shoot.

The trigger is light and crisp (actually a little lighter than my preference), and she's heavy and solid.
No complaints about the gun at all.

The problem I am having is nothing new to most of us, but seems worse on this gun than most of my others. The scope migrates appreciably and gradually, in spite of having a nice one-piece mount, which I have tightened several times. It still wants to move.

One of the things I like about the old Dianas with the T05 trigger, is the scope rail...it facilitates locking down the scope with minimal effort.

Okay....now to the question-
Can a gunsmith drill scope stop hole(s) on the scope rail without causing any damage to the gun itself?
I've never had any work done by a gunsmith, and I know that they can do so on PB's (I remember the hubs having that done at one time many years ago), but I am also aware that the steel used on air rifles tends to not be quite as hard or tough as that of PB's...at least that is my understanding, based on multiple sources I have read over the years.

Is there something else I am not thinking of that would be a good fix or solution?

I retightened the scope mount down, took it out to shoot just a few shots, and I could already see that is has moved.
Sigh.....

[mentolio]

Be careful, my experience has been that "gun smiths" (at least in my area) see air guns as toys, and don't take them seriously at all. One way ticket to a botch-job and heart-ache, this I learned the hard way...Try to stick with guys who do actual air gun repair. Plenty of guys 'round this here forum. Best of luck!

[lizzie]

Excellent advice Jeff- thank you!

[Taso1000]

Lizzie,

There are these:



But without a stop hole I don't think they'll be better than what you already have.  Is your scope rail removable?  I'm not familiar with your rifle.

Taso

[Privateer]

Don't take an Air Gun to a GunSmith that never worked on Air Guns!
It's 2 different Worlds.

[lizzie]

Lizzie,

There are these:



But without a stop hole I don't think they'll be better than what you already have.  Is your scope rail removable?  I'm not familiar with your rifle.

Taso

No- not removable.
The scope rail on the R1's is very similar to dealing with one of the Gamo scope rails.
Slick and smooth as can be, and no stops of any kind cut into the steel, as I have seen on a few guns.

The photo below of the entire gun isn't mind- it's just to give you an idea of what the gun is.
The other two photos, I took a few minutes ago.

[SagaciousKJB]

I've heard of some people using loctite on the rails where the dove-tail attaches and between the scope tube and straps  I'm not sure how this would actually work, I'm guessing in the same way it locks threads down.  Superglue might do the same work, but I wouldn't trust it between the scope straps and the tube.

I don't think you'd have a problem with drilling a hole as far as structural integrity goes.  That steel may not be as tough as PB's steel, but it's still tough enough to hold the spring in under compression with pins bolted through it. 

On the other hand, I've seen the screws themselves take some damage, get bent, jump out of the hole and gouge up the receiver.  So they may not really be the solution you need. Maybe ask nced, I know he posted some pictures of a gouged scope stop on one of his Beeman R*s and his actually has 3 holes in line.  I'm not sure if that was because it needed 3, or if it was just for more configuration options.

[lizzie]

Thanks SKJB! Great idea! (to ask nced)

[dv8eod]

Have you measured the rail? It might be smaller than the rings can clamp. Another thing to look at is how fully the clamps seat in the grooves. A little file work to make the clamps fill the grooves completely should give more surface area to allow friction to keep them from sliding. I mean filing on the clamps and not on the gun, jic...
Just some things to look at. Rings are cheaper than a new gun. Hope this helps.

[lizzie]

It does help, Terry. Thanks!

[dv8eod]

I had a similar problem with my first break barrel/scope combo, only it wallowed out the stop hole. The rings were only clamping to the center and top of the grooves. I took me a couple of weeks to file them to fill the whole groove, but when I finished they didn't slide. I left the filed areas slightly rough to let the marks dig in and help with the holding. I spent too much time on that tomato stake before I found this site and realized there were real airguns out there... 😁

[lizzie]

Hahahah

[Taso1000]

Lizzie,

Maybe these Millett Tip-Off rings may work:



The only problem is getting them centered as the left and right sides adjust independently.

Taso

[lizzie]

Interesting Taso! I've not seen nor heard of those before...I will check around on them. It would be great if they worked for this particular problem!

[Roadworthy]

There are 3/8" rails and 11 mm rails.  They are dimensionally close but quite different.  One is cut at 45 degrees and the other at sixty.  Many scope mounts have one removable side plate.  If you have one of these see which projections fits better into your dovetail.  That is the one to use for scope mounting.
My Diana 35 was plagued with a wandering scope.  As I'm sure you're aware that was made before Diana began using the add on rail so there is no place for a mount with a toe and of course no scope stop holes.  I cleaned the grooves and the mount well with a degreaser (or maybe just alcohol, I don't remember), applied Loctite in the grooves, and installed the mount.  I then torqued it to thirty inch pounds.  My scope has stayed put ever since.
One key part of the procedure is to use a torque wrench to tighten the mount making sure all screws are tightened evenly.  I start at the center and work out tightening five to ten inch pounds at a time, kind of like torquing the head on an engine.

[redtrucker610]

I had used red loctite on the scope rail on my HW90. I never had a problem with the scope moving after I did that.

[Robert Skelton]

I would use super glue (it's clear) or lock tight, but also have used finger nail polish. Lot's of color choices there.

[lizzie]

So, you guys are saying you just put loctite down into the dovetail groove, and place the scope mount, essentially "bedded down" into it?

[Novagun]

Lizzie, looking at your photos there is no scope rail on your gun, just grooves. The only way to put a stop pin on that gun is to drill into the compression tube. Please don't do that. The steel is not thick enough to be effective, apart other obvious bad points.
The add on scope stop that you have been referred to do work, better on a two piece mount because you can put one behind each mount. In your case it may not work too well because you might have to move the single piece mount too far forward to get room for the additional scope stop. Maybe not.
 
Gamo make an alloy scope rail that goes on the grooves in the compression tube and it can be drilled for a stop pin where ever you want it. The rail clamps on and the mounts clamp on top of it. It is good and does not move. It raises the scope about 5 mms/ 1/4 inch. I think other outfits make them as well as an accessory. Gamo and Weihrauch have 11 mm groves so it should fit.

I am going over to Wainuiomata for some Gamo bits in the next couple of days and will see if Mr Gamo has one lying in the treasure bin.

Some of the stop pins on scope mounts are too thin and I have had them break off but it is easy to put in a more substantial pin.

[lizzie]

Lizzie, looking at your photos there is no scope rail on your gun, just grooves. The only way to put a stop pin on that gun is to drill into the compression tube. Please don't do that. The steel is not thick enough to be effective, apart other obvious bad points.
The add on scope stop that you have been referred to do work, better on a two piece mount because you can put one behind each mount. In your case it may not work too well because you might have to move the single piece mount too far forward to get room for the additional scope stop. Maybe not.
 
Gamo make an alloy scope rail that goes on the grooves in the compression tube and it can be drilled for a stop pin where ever you want it. The rail clamps on and the mounts clamp on top of it. It is good and does not move. It raises the scope about 5 mms/ 1/4 inch. I think other outfits make them as well as an accessory. Gamo and Weihrauch have 11 mm groves so it should fit.

I am going over to Wainuiomata for some Gamo bits in the next couple of days and will see if Mr Gamo has one lying in the treasure bin.

Some of the stop pins on scope mounts are too thin and I have had them break off but it is easy to put in a more substantial pin.

Thanks! And you're right....I realized after having posted, that I had misspoken and called the dovetail grooves a rail- not thinking!
I prefer a rail, as it's much easier to deal with, and superior in performance (imo).