Make A Recoil Proof Scope Mount
For A Contender

Copyright 2012 by Junior Doughty
(7-23-12 & 11-13-12 updates at bottom or Click here.)
Ready-to-install 92A recoil proof scope mount for sale at the very bottom. Click here.

On the top right see my Contender 10" bull barrel 7mm TCU. Below it see my Contender 14" bull barrel 7mm TCU.

I never liked hunting with the 14" barrel due to its awkward weight-forward handling. But the 10" barrel handled naturally and easily. After hunting with it during the 2011-2012 season, I started looking for a 10" bull barrel in 30-30.

Why 30-30? Well, I had 14, 30 caliber bullet molds. I had several boxes of ammo loaded for my 30-30 Model 94 Winchester rifles. Plus, I had thousands of 30 caliber cast bullets in every stage from as-cast to Ready To Load.

But let's face facts—mainly, I wanted a 30-30 barrel for my Contender. I wanted a 10" bull barrel like my 10" 7mm TCU barrel, and I wanted it set up exactly the same. I liked hunting with the 10" bull barrel and 2X scope.

So I found one in 30-30, used but like new. When it arrived, I left the iron sights on it and started running rifle loads through it and over my Chrony. My 20" barrel, rifle-load deer hunting bullets were the Lyman 311041 @ 178 grs, the Ranch Dog TLC311-165-RF @ 176 grs and the RCBS 30-180-FN @ 195 grs—all in acww alloy and twice-lubed with Lee Liquid Alox and Lee push-through sized .309".

The 20" and 10" velocities with the same loads were:

  • Lyman 311041 @ 178 grs. . . . . 20" = 1725 fps; 10" = 1396 fps (light hunting load)
  • TLC311-165-RF @ 176 grs . . . 20" = 1750 fps; 10" = 1488 fps (light hunting load)
  • RCBS 30-180-FN @ 195 grs . . 20" = 1973 fps; 10" = 1655 fps (heavy hunting load)

Through the scope-less 10" bull barrel, the RCBS 30-180-FN load kicked hard—too hard for me. It certainly wasn't a load I'd want to use on a beer can unless the can was in the mouth of a bear. No, I would deer hunt with the other bullets. With them, subsequent heavier loads using Varget increased the 10" barrel velocities to 311041 = 1686 fps and TLC311-165-RF = 1729 fps.

Those recoil levels were tolerable. Increasing the pistol's weight with a scope would make them even more tolerable. So for the 30-30 barrel, I ordered a 2X Burris pistol scope and a Weaver 92A scope mount, both exactly like on my 10" 7mm TCU barrel. (Except for the "Made in the Philippines" sticker on the new scope.)

For rings, I ordered Leupold PRW steel rings # 54149 Medium Matte. They would be heavier than the aluminum rings on my 10" 7mm TCU barrel and, therefore, help decrease the recoil level. (Note: 2-25-13: They would also increase the recoil stress on the scope mount as you will see later in this article.)

My scope stuff finally arrived.

First step, I removed the iron sights from the 30-30 barrel. The six screw holes in the barrel were clogged with thread locker, so I spent several minutes cleaning them. Then I installed 6-48 slotted plug screws in the two front sight holes.

The rearward plug screw fit flush, but as you can see in the "Before" and "After" photo of the front screw, it stuck up a lot, probably due to the slight taper of the barrel.

Click for full size popup photo

 

I easily shortened it with a file and one of the screw shortening jigs I sell here.

This photo shows the front of the jig and not the rear with the paint scraped off by several files over several years. It has a 6-40 hole, a 6-48 hole as you see here, and an 8-40 hole. This jig has shortened dozens of screws and plug screws.

You see the shortened 6-48 slotted plug screw on the left and a new one on the right.

Click for full size popup photo

 

Next I turned my attention to the four scope mount holes.

The factory tapping job had left little rims around the holes much like tiny bomb craters. As I wanted perfect mating of mount to barrel, I used a file on the hole rims and made them level with the surface of the barrel.

My intentions were to glue those mating surfaces together with a very thin layer of epoxy. I wanted a tight fit. The 195 gr RCBS load kicked. Kick = recoil = loose scope mount potential. By golly, this scope wasn't shooting loose!

The barrel finally nice and smooth around the scope mount holes, I placed the mount in position on top of the barrel. I then held it up to a light and looked at the mount/barrel junction to see if maybe I'd missed a crater rim. Lo and behold the sight on the right greeted me. It was an Oh, Shiite! moment.

As I couldn't capture the sliver of light with my camera I drew it in with a "Paint" program. If you'll notice, the gap is about 3/4 the size of a 30-30 case rim.

The mount, the proper Weaver 92A, would have perfectly fit the curvature of a barrel smaller in diameter than my .804" diameter 10" bull barrel. It was made as a one size fits both Contender barrels and Rossi single shot barrels. It would not work on an application called, "By golly, this scope wasn't shooting loose!"

Hand cannon shooters take note!

I stopped the mount installation process and pondered my options. Option #1 = fill the gap with epoxy; option #2 = make it fit.

I chose the latter.

Click for full size popup photo

 

I took a piece of emery cloth, wrapped it around the barrel, then began sanding the aluminum mount bottom to perfectly fit the top of the steel barrel.

Yes, this process scratched the barrel bluing a little.

As the aluminum mount was much harder than expected, the process took about thirty minutes, maybe more.

I used "Fine Grit" emery cloth, but I think "Coarse Grit" would have worked better and faster.

Update 3-21-13: Use the shank of a long 3/4" bolt instead of your barrel. The thickness of the coarse emery cloth added to the bolt diameter almost perfectly matches the barrel diameter.

Click for full size popup photo  

 

 

Here's a look at the bottom of the mount just before I stopped sanding.

I stopped sanding when the emery cloth started scratching the inside center of the mount.

 

Click for full size popup photo  

 

 

Finally, a check showed this—a perfect fit of surface to surface.

There was no to almost no sliver of light between mount and barrel.

With a thin layer of epoxy between the mount and the barrel, I had a recoil proof scope mount—or so I thought.

 

 

 

Click for full size popup photo Later, I put the mount back on the barrel and admired my handiwork. Only this time my finger pushed down not over the rear of the mount but over the front of the mount.

Notice the gap in this picture vs no gap in the picture above it. You can see it clearly in the full size photos. Something was wrong, obviously.

I fiddled with the mount atop the barrel. My finger over the mount's rear ring slot, the gap disappeared. My finger over its front ring slot, the gap appeared. The reason hit me—the barrel tapered starting just past the forward screw holes. The mount moved up and down like a seesaw with its fulcrum just past the forward screw holes.

Due to Newton's first law of motion about an object at rest wanting to stay at rest, the pistol recoils backward and the scope effectively recoils forward in relation to the pistol. The result is downward recoil force on the front scope ring and upward recoil force on the mount screws.

As the front scope ring is supported only by the aluminum mount and with a gap beneath the mount, the effect is like the recoil force of every shot hitting the top of the front ring with a hammer. In other words, a loose mount is inevitable without filling in the gap.

Here's a "Paint" picture for a better explanation. The red dots represent the mount screw holes. The blue triangle is the seesaw fulcrum, i.e., it's the point where the barrel taper starts. Beneath the front scope ring, the barrel diameter is .786" vs .804" beneath the rear scope ring.

The white arrows show the recoil force on the pistol, bottom, and the effective recoil force on the scope, top. Imagine the stress on the scope mount screws in the expected forward direction and in the unexpected upward direction.

Without eliminating the seesaw fulcrum shown here, i.e., filling the gap beneath the front scope ring, this scope would eventually shoot loose.

Click for full size popup photo Look at this almost-in-proportion drawing which represents 1-only thread of a 6-48 scope mount screw. Look what upward recoil force indicated by red arrows does to the screw thread. Think of the upward recoil force like the blow of a hammer. As you can see, the force works to loosen the screw.

Click for full size popup photo  

Here we see the final results—a recoil proof T-C Contender scope mount.

Click for the full-size version and you can see where epoxy has oozed from beneath the mount.

Not shown, and of more importance, is the epoxy which has oozed from beneath the mount's front, non-elevated edge.

I also assigned each of the four mount screws their own hole in the mount/barrel. Prior to smearing a thin layer of epoxy between the mount and barrel, one by one I tightened each screw through its hole in the mount and made sure it did not bottom out in the hole and leave the mount loose. I wanted no surprises like I recently encountered with partially-tapped old Redfield rings.

Click for full size popup photo Here's a look down at the mount and an explanation of something I wish I had done from the viewpoint of 20-20 hindsight.

Muzzle to the left, A & B mark the mount screws. C marks the mount slot against which the front PRW ring locks. The fulcrum lies just to the left of B. Just left of the C slot at the red X, I wish I had drilled and tapped a hole and installed a 10-32 x 1/4" hex head set screw. (Sold here.)

I would have put Loctite® in the threads and snugged the tip against the barrel through the wet epoxy already there. The circa .025" thick layer of epoxy filling the gap beneath the front of the mount would have had failure insurance. The hex screw would have shared the downward hammer blow-like recoil force.

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For those with recoil concerns, like me, here's the Recoil Energy numbers with the three bullets above, average powder weight of 25 grs, and a final total pistol weight of 3.8 lbs.

  • Lyman 311041 @ 1686 fps = 14.5 ft.lbs
  • TLC311-165-RF @ 1729 fps = 14.8 ft/lbs
  • RCBS 30-180-FN @ 1655 fps = 16.1 ft/lbs
As a comparison, the Recoil Energy of my 10" bull barrel 7mm TCU ( total pistol weight of 3.7 lbs) with the heaviest load I shoot in it, a 175 gr Hornady or Nosler bullet @ 1600 fps, is 13.5 ft/lbs. That's pussycat recoil level compared to the three cast bullet 30-30 loads shown above. However, I suspect it will eventually shoot loose the non-reinforced scope mount. When it does, I know how to fix it.

In conclusion I repeat, Hand cannon shooters take note!

Update 7-23-12  

Muzzle to the left, below is a look at the Weaver 92A scope mount on a new-to-me 222 Rem 10" bull barrel. Let me start by saying, A 222 Rem Contender isn't a hand cannon!

Click for full size popup photo When I received this barrel, with a scope mounted, all 4 of the scope's ring screws and the 2 clamping screws were barely hand tight. I tightened them, and I thought nothing about it until I got ready to shoot the pistol. Then, beneath the scope, I noticed the silver spot you see here at screw #3. Off came the scope.

There was no screw in hole #3. A previous owner had wallowed out the #3 hole with an electric drill, probably to remove a boogered screw. Screws #1 and #4 were barely hand tight. Screw #2 was tight.

The fulcrum effect and years of tightening and retightening loose screws by probably several owners had nearly ruined this mount. It's a miracle none of the 6-48 holes in the barrel weren't stripped. I almost ordered a new mount, but my tinkering instincts took over. So I spent several hours working on this mount and its screws.

  • I installed a 10-32 x 1/4" set screw (sold here) at the #5 position in order to stop the fulcrum effect. The 1/4" set screw fit perfectly, stopping even with the top of the mount. A thin daub of JB Weld on both sides of #5 helped stop the seesaw. I installed the 10-32 x 1/4" set screw last, and I just snugged it against the barrel.

    Note: Make sure the set screw's trailing edge is forward of the mount slot!

  • I did some wallowing of my own in hole #3. I mangled the wallowed-out aluminum sides of the hole with a screwdriver blade used like a punch until a new 6-48 Weaver screw (sold here) would seat and clamp down the mount with no wiggle. I tried several different lengths until one clamped the mount down without bottoming in the hole.

    I almost filled in the wallowed-out hole with JB Weld and re-drilled it, but the screw as you see it here had good purchase on two opposing sides of the wallowed-out hole. So I left well enough alone.

  • Screw #2, the only really tight screw as this project began, was bottomed out in the hole and doing zilch to secure the mount, which wiggled with #2 tightened hard. I replaced it with a shorter 6-48 Weaver screw and stopped the wiggle.

Unlike the 92A mount described above, this 92A mount perfectly matched the contour of this .804" diameter 10" bull barrel. Weaver needs to explain that fact!
When I received this barrel, this mount had only 2 of 4 screws clamping it to the barrel—#1 and #4. And they weren't fully tightened. But that wasn't all.

Every one of the scope mount screws had boogered heads from repeated tightening and retightening. The threads on all the screws were clogged with rock-hard thread locker, which a stainless steel brush wouldn't completely remove. That and the boogered heads is why I replaced them all. With a pin, I had to clean the thread locker crust from the four tapped holes in the barrel, and I had to chase the threads with a 6-48 bottom tap.

Then when I removed the rings from the scope, some sort of sticky tape was on the inside of both rings. All this on a low-kick 222 Rem! The previous owners of this Contender barrel probably scratched their heads in wonder of why the scope on a pussycat 222 Rem kept shooting loose. You and I know the reason—the fulcrum effect.

The Recoil Energy of this 222 Rem is only ~ 5 ft/lbs. If over the years it almost demolished a scope mount due to the fulcrum effect, what does the mount on your 44 magnum look like? I repeat, Hand cannon shooters take note!

If the scope on your Contender changes zero or shoots loose, you probably have a fulcrum problem.

  • First, check all four scope mount screws to see if one—or more!—is bottoming out in the hole. The hole could have trash in it or could be too shallow. If one is too shallow, you can trim the screw with the screw jig sold here or replace it with a shorter screw. Align the mount screws on your bench in some way so you can easily put them in their own holes.

    Tighten a screw in its hole and check the mount for wiggle. Then remove the screw and check another one in its hole. Don't be surprised if at least one screw is tight and the mount wiggles.

    If the mount wiggles, you're a victim of "Tolerance Stackup." (Google it.) You have a screw on the long side of its length tolerance in a hole on the shallow side of its depth tolerance.

  • To stop the fulcrum effect you'll need a 10-32 x 1/4" hex set screw also sold here. I suggest buying a 10-32 x 5/16", a 10-32 x 1/4" and a 10-32 x 3/16" in case your mount is thinner or thicker than mine. To install the set screw you'll need a 10-32 taper tap and a #21 HSS drill both sold here.

  • You'll need a trace of JB Weld or epoxy on the bottom of the base. Just a trace, please. And de-oil the base and the barrel, please. Don't forget thread-locker on the base screws and epoxy on the added set screw threads.

Good luck!

Update 11-13-12  

Sad to say, but my 70-year-old eyes suddenly couldn't see the fiber optic sights on my 10" octagon barrel T-C Contender 357 Mini-Max pistol. So I installed a 2x20 Leupold scope on the barrel. As I shoot a 190 gr cast bullet @ ~1700 fps in the pistol, I wanted the mounts & rings as recoil proof as possible. This barrel is a hand cannon in anybody's book.
This third 92A Weaver mount was almost as small in diameter as the one I used on the 30-30 barrel above. Out of 3, 92A Weaver mounts used in this article, only one fit properly.

I used a new 92A Weaver mount, and it required lots of emery cloth work. I also used an old set of Weaver clamp-on rings from my junk drawer. The picture below shows the old rings mounted and tightened down.

I replaced the 4 original 6-40 x 5/16" Fillister head ring screws with 4, 6-40 x 1/2" T-10 Torx Fillister head screws for recoil insurance. (Sold here) That required cleaning out all 4 tapped ring screw holes with a 6-40 bottom tap. (Sold here.)

Click for full size popup photo Luckily, the holes were all drilled deep enough for 1/2" screws. Each hole now has (1) a Torx screw capable of much greater clamp-down torque; and (2) about 9 extra threads purchase. In other words, all 4 ring screws now have much greater recoil insurance.

The red X marks where I installed a fulcrum effect stopping 10-32 x 5/16" set screw through the Weaver mount and touching the octagon barrel. The smaller diameter octagon barrel necessitated using a 5/16" set screw instead of a 1/4" like on the bull barrel above.

The blue line marks the fulcrum point. It's easily visible without the blue line because
it's the point where the octagon flats start. Plainly visible is the gap under the bottom of the mount to the left of the blue-marked fulcrum point. Without a setscrew at the red X this entire scope/rings/mount system would seesaw with every shot.

Not visible is the 4, 6-48 T-10 Torx Weaver head screws I used to install the 92A mount. That step wasn't easy and probably wasn't necessary. But the added torque plus the extra thread purchase gained via perfectly fit-to-length screws made the work worthwhile, I believe.

As I did with the two mounts above in this article, I assigned each of the four mount screws their own hole in the mount/barrel. Only these 4 mount screws were Torx screws.

Image is full size Sitting on a screw shortening jig and on the left in this photo, see one of the slotted Weaver 6-48 x 3/16" screws which came with the 92A mount. On the right see a new T-10 Torx Weaver 6-48 x 1/4" screw like the ones I shortened and used to install the mount.

Notice the tapered tip of the slotted head screw. The tip is tapered for an easy start in a hole, but the taper removed about one full thread. A screw in a hand cannon barrel needs all the threads it can get.

I used a screw jig, a micrometer and a file, and one by one I shortened each Torx screw for a perfect flat-tip fit in its own hole. When a screw seated deep enough that the mount didn't wiggle, I filed an extra .004" off the screw. That gave each screw about 1/4 turn bottom-out clearance. As mentioned above, align the removed screws somehow so you can positively put each screw back in its own mount/barrel hole.

Note: A bottomed out scope mount screw might as well not be there!

I spread a thin layer of epoxy on the bottom of the 92A mount, then installed each screw in its own hole, then torqued them down with all the strength in my wrist. This scope isn't shooting loose.


The mounts for sale below were altered for recoil resistance as described in the article above. They are as recoil resistant as possible without going to high-$ 6-hole mounts and drilling & tapping two extra holes in your barrel. The bottoms were sanded down for a perfect to near-perfect match to a ~.804" diameter Contender barrel contour. Then a fulcrum effect stopping 10-32 set screw was installed near the front of the mount.

Detailed Instructions

USA sales only!      

Weaver 92A recoil resistant scope mount for old model Contender 10, 12, and 14 inch bull barrels. $25 + $3 shipping and handling.

Weaver 92A recoil resistant scope mount for old model Contender 10" octagon barrels. $25 + $3 shipping and handling.

1. Important! Make sure the four 6-48 mount screws do NOT bottom out in your barrel as described in the article above!

2. De-oil your Contender barrel in the scope mount area. I use rubbing alcohol. Consider this installation as permanent!

3. Put a VERY THIN smear of epoxy on the bottom rear half of the mount in the area which touches the barrel behind the fulcrum point. DO NOT get epoxy close to the 6-48 holes.

4. Put thread locker on the 6-48 mount screws and install the mount on your barrel.

5. Put a touch of epoxy on the 10-32 set screw threads and snug it against your barrel after the four 6-48 mount screws are tightened. I said snug and after! Do not tighten the 10-32 set screw! Snug it!

6. Wait 24 hours and install your scope. Choose both scope and rings for light weight. Push the ring recoil lugs forward against the front of the mount slots, not back against the rear of the slots!

7. If you perform the installation correctly and your mount shoots loose, return it to me for a 100% refund of the $25 purchase price.


Parts & Tools List

  1. Emery cloth & a micrometer & a file & epoxy & thread locker.

  2. Screw jig.

  3. 6-40 bottom tap for your rings maybe.

  4. 6-48 bottom tap to clean out the barrel hole threads and for your rings maybe.

  5. #21 HSS Tap drill for the 10-32 tap. A center punch is nice for making a start dimple.

  6. 10-32 taper tap for the fulcrum effect stop screw hole. Clean the oil out of the tapped hole!

  7. A 3/16" a 1/4" and a 5/16" 10-32 set screw. You'll need a 3/32" hex wrench or bit.

  8. 5 new slotted Weaver 6-48 x 3/16" screws if you use your old mount. A new 92A mount comes with 4. You only need 4 but get an extra for Murphy. They're little tiny things and hell to find on the floor.

  9. 5 new T-10 Torx Weaver 6-48 x 1/4" screws if you plan to go the Torx route. You'll need a T-10 Torx bit.

Except for #1 all items are sold on this site here and here.

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