View Full Version : Epoxy scope bases?

December 20, 2010, 03:52 PM
I know this smacks of bubba gunsmithing, but I have a "sporterized" M1917 Enfield that I paid $100 for. I would like to put a scope on it, but it's not drilled & tapped. I was thinking of epoxying the bases on. I hate to spend $100 to have it drilled & tapped. It might actually cost more as the "swimming pool" was never filled in when the ears were ground off. Also some gunsmiths run screaming when you mention drilling & tapping a M1917 Enfield. Any thoughts would be appreciated, but no comments about my mother.


December 20, 2010, 04:31 PM
The problem with expoxy to mount scope bases is finding the right stuff. You need a very tough material to withstand the forces, standard "Walmart two-part epoxy" will last a good while, and then your scope will fall off due to brittle failure. If you're lucky, it's during the hunt and it will land in mud, if not, it will land on the concrete base of your range.
The second issue is to find a base that is truly conformal with your receiver. Adhesives do well at a given very precisely held thickness, and fail miserably if your base sits metal to metal on the sides and is hollow in the center. This greatly enhances your issues of thermal expansion mismatch, your receiver will expand differently from the epoxy and, worst case, the aluminum bases. And for a gun with conceivably a 200 F difference between cold winter and hot barrel, these thermal issues are huge.
We've experimented here with some really high strength stuff that gives you 4000 psi in shear, but that stuff is $50 a jar from specialty stores selling to marine equipment makers to glue in fiber reinforced masts.
Oh, and the problem of getting the glued bases aligned to +-10 MOA so you can still center the scope.
I'd say the gun smith is the easier option.

December 20, 2010, 07:41 PM
The short answer is: Epoxy will not hold a scope on a rifle.
The mount would probably pop off with the first or second shot.

If adhesives would hold a mount on, manufactures would be using it instead of expensive drilling and tapping of holes.
They don't because it won't.

December 20, 2010, 08:49 PM
I know you're right, but I want to try it with Gorilla Glue. I need to find a cheap gun and scope, I have the glue.

It would be a mess to look at considering how much the stuff foams up, but I'm impressed with its holding power after using it for a few years.

The Gorilla Tape is almost as good, but will come off if need be.

December 21, 2010, 07:53 AM
The problem with glue to hold base and rings and scope is that glue is not made to with stand the shear force on firing.
The gun fires and moves but interia cause the scope to stay in place.
Of course with screws it does the same but the screw has a mechanical joint


December 21, 2010, 07:56 AM
I have used both for bigger kicker and light weight guns and heavier scopes.

Ideal Tool
December 21, 2010, 08:41 PM
Red Green woulda used camo duct tape!

Ideal Tool
December 22, 2010, 02:04 AM
Sorry about that last crack...couldn't help myself! On a more serious note...I'm at work, and for some reason kept thinking of your problem...Have you thought of soft-soldering steel bases on? I'm thinking low temp. silver solder would more than likely require too much heat in this critical area..but a good strong solder shouldn,t hurt. I know the Germans used to solder ribs &
claw mounts on their sporters. And of course the British used it on their double rifles. Best of luck!

December 22, 2010, 03:24 PM
I have tried the epoxy alone. The scope pops off with the first shot.

I have drilled and tapped ~100 rifles. You may be able to do it yourself.

December 22, 2010, 07:06 PM
No, no, not duct tape!
Hose clamps.

But seriously, as has been said, glues and epoxys are pretty good in tension, but not so good in shear.
For something as hefty as a scope and mount, mechanical attachment is best.
Does anyone make a receiver side mount to hold a scope for this gun?
Preferably one that uses existing pins or screws?
Just a thought.

December 22, 2010, 08:26 PM
Gorilla Glue is no where near as strong as a good epoxy.

If you absolutely must try it, buy a high grade epoxy from Brownell's.

December 23, 2010, 05:08 PM
Although using hose clamps intrigues me, I took my Enfield to a gunsmith for drilling & tapping. It will cost $60 ($40 to drill & tap; $20 to fill the swimming pool). I can't wait to see how it does at 100 yd. once I mount a scope.


December 23, 2010, 11:22 PM
A late friend of mine serviced helicopters in Vietnam (in Thailand, actually, but for the war). He told me the skin of helicopter rotary wings is held onto the frame with a Boeing adhesive. There are some tough glues out there, but they are mostly industrial products with a specific bonding requirement. For example, we all know what super glue is. Get an industrial super glue catalog and you'll find you've got twenty or thirty to choose from. One's best for rubber on glass, another does aluminum to PVC, etc. You'd want aluminum to steel, but I'll bet you'd have to scrape the profiles to a fit before it would work.

December 24, 2010, 12:12 AM
but I want to try it with Gorilla Glue.

Gorilla glue does not work well with non-porous, smooth surfaces.

December 24, 2010, 03:02 AM
The wing skins on later B-52's are epoxied on as well.

My guess- a bolt action probably flexes too much. Drill and tap.

December 24, 2010, 08:19 AM
The wing skins on later B-52's are epoxied on as well.

The skins do not see the kind of shock loading a scope mount does.

December 24, 2010, 08:57 AM
Once upon a time I used epoxy to help me locate the bases on a 98 Mauser for home drilling. I mounted a factory new (and therefore centered) scope and clamped the bases to it at the correct spacing. I then clamped the rifle in a vise and 'bore sighted' the scope and bases so they were correctly aligned and then epoxied the bases in that position.

After it hardened I removed the scope and just drilled through the holes in the scope bases. It seemed to work OK.

December 24, 2010, 11:27 AM
After it hardened I removed the scope and just drilled through the holes in the scope bases. It seemed to work OK.

As a way locate for drilling it works.

It also can be used to fit bases to a less than perfectly machined action, but the screws are doing most of the real holding.

December 24, 2010, 04:52 PM
JB weld :p

Bill DeShivs
December 24, 2010, 06:48 PM
I was waiting for that! :rolleyes:

December 25, 2010, 01:10 PM
Brazing might of worked but looks bad.:barf: J B Weld would work if you got them cleaned up good,,,,,,you're not serious really?,:rolleyes: Totally DO NOT GLUE ANYTHING TO THAT RIFLE!!!!:mad::(:rolleyes: (unless its a picture of your girlfriend);)

December 29, 2010, 03:29 PM
My Dad glued everything with JB Weld and epoxy, but for this purpose it would fall off and likely ruin an optic.

January 5, 2011, 02:58 PM
IF you use any type of adhesive put a short length of nylon cord around both the scope and the rifle. A short leash will keep the scope from hitting the ground too hard.

January 12, 2011, 08:31 PM
Why not just bust out the tig wielder it would work alot better

January 13, 2011, 05:36 AM
B-Square Scope Base & Rings for US 1917 Enfield (http://www.gunsamerica.com/903612485/Non-Guns/Scopes/Mounts/Rings-and-Optics/Mounts/Traditional-Weaver-Style/Flat/B_Square_Scope_Base_Rings_for_US_1917_Enfield.htm)

I think this is the one I was going to buy for mine a few years ago. There was no drilling or tapping involved.

I don't think it would be all that stable; it seemed to be held by the single screw holding the ladder sight on.

January 13, 2011, 12:40 PM
M14, let's get back to the original issue: why is it going to cost $100 to have it drilled and tapped? You could probably do the job yourself- the only way you could screw up is if the spacing is off. What I have done is to find a tube (hobby metal- ACE hardware) that fits inside the tapped holes in the base. I then "tack" or temporarily glue the base in place and drill the holes. They should be dead center. These may have to be expanded just a little with the proper drill for the tap but generally you'll be right on the money. You'll need a regular tap and a bottming tap.
Question: what about one hole drilled and tapped and the other hole with a steel pin and everything epoxy glued (putty type epoxy) I've never done it but it might hold. If it would hold- that could be an option if you screwed up on the spacing for the second screw on a base.
I've never done this, I always knock off the base after drilling with the tubes and then tap but I suppose you could tap one hole, put on the base and then run the tap down the threads of the second hole on the base and right into the second hole you drilled- that ought to cut a perfect tread- alignment.
Anyone ever do it that way?

January 13, 2011, 02:03 PM
You can drill & tap it yourself. the hard part is making sure you are lined up correctly.