I didn't realize how much of a pain it is to scope a double rifle. I want to put a 1.5X5 leupold, or the like, on my 9.3X74R chapuis. Unfortunately, there is not an american company that makes a scope mount for a Chapuis double that I can find. I was told I could order one, but that it would cost close to $400.00. I was also told that it might mess with the regulation.

Can anyone here give me some info. with regards to finding a scope mount for the Chapuis? And, will it actually affect the regulation, or is that just wrong?

SHOWBART- Thanks for all the help with this. I'm looking to see if anyone else has any ideas or has done this themselves.


Thanks fellas.

Like this?




Do a search, there's probably a good dozen times this has been answered in the past 6 months.

My apologies. Haven't been around that long. An answer would have been better though. Thanks.

Order the pivot mount and rings from JJ Perodeau at www.champlinarms.com

Yes it will be fairly pricey, but they do go back to zero 100%.

Those are the ones in the above picture.

Yep, Wales, this is the place and 450 NE No2 always gives sound advice. Like I said I'd never heard here of one needing reregulating except for JudgeG and I forget why on his.

Yes, JJ may have them in stock. If Recknagel they'll still be like $385. Don't know if EAW or who else may make a setup. Those I spoke to about it said there's always the chance it needs reregultaion. That's of course shooting irons with new mounts and the scope removed. The scope regulates itself. Mark at NECG said he had a customers gun need reregulating after installing a recoil pad! More scare tactics, it's always a worst case scenario.

quote:

Originally posted by Showbart:
Those I spoke to about it said there's always the chance it needs reregultaion. That's of course shooting irons with new mounts and the scope removed.

No, it isn't. It's shooting it with the scope attached.

quote:

The scope regulates itself.

No, it doesn't.

maddenwh:

No, mounting a scope on double properly isn't cheap, and sometimes it's an expensive headache. The pivot mounts for the Chapuis are pretty cheap. The best way to mount a scope on a double is with claw mounts, but those will run $1000 or so.

Although it probably won't, adding a scope CAN throw regulation out. "Regulation" is the process of adjusting the convergence/divergence of the barrels so that they shoot to a common point of impact. What governs regulation is the recoil arc away from the point of aim during barrel time (recoil movement while the bullet is still in the barrel). Put another way, double rifle "regulation" is slaved to this recoil movement. When adding a scope and mounts to a double that was regulated with irons, you're adding considerable weight in the most critical spot. That weight dampens recoil, potentially changing recoil movement during barrel time enough to cause a materially adverse effect on regulation - the barrels don't print together anymore. When that happens, you have to make a choice of scope vs irons. You can leave the regulation alone so that it's accurate with irons and zero the scope to one barrel (and use it like a single shot when using the scope), or re-regulate it for the scope.

I've never heard of the addition of mounts alone causing a problem. It's the combined weight of the scope and mounts. When adding a scope screws the regulation, it should still shoot as well as before with the scope detached. Nor is the scope "self regulating" in any way. If the regulation changes, there's no adjustment on the scope that will move the barrels back together - only re-regulation can do that.

Given the why of it, you'd think regulation would always change when adding a scope. The reality is that you get away with it most of the time - but sometimes you don't, and there's no predicting which it will be. I remember a .450 Nitro that came with claw mount bases, but no rings or scope that Bill Reinie at Champlin's then made rings for. He got teacup size groups with the sights at 100 yards, but with the scope attached the groups grew several inches. Another poster here, 308Sako, had a similar experience with a .30-06 double rifle.

You probably won't have any trouble with it, but sometimes it does happen.
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"Serious rifles have two barrels, everything else just burns gunpowder."

I was thinking scope adjustment might bale one out of a minor change in regulation. I can see that that is a flawed way of thinking about it.

I have scoped 5 doubles over the last few years,four 9.3x74r and none required re-regulation. Just lucky I suppose. Two were Valmet O/U's with factory mounts. One was an Otto Geyger in 8x60RS and originally had claw mounts. Removed front dovetail base and made custom bases for Leupold Dual Dovetail rings. Not a big job at all. Scopes in all cases were Leupold VariX-III 1.5x5. Chapuis UGEX had blocks removed and portions of Ruger No1 Ribs inserted using same screw holes. Used Ruger Rings. Again not a major job and I believe you MIGHT be able to just remove the Chapuis blocks and machine the thumbnail cuts and the cross slot for Ruger rings. I wanted to be able to restore to original easily. Merkel 141 8x57JRS I currently have has MAK pivot base that I installed in a measured 15 minutes. Cost of mount/rings $520. Delivery one week. This rifle puts 2 lefts 3 rights in .630. Swift 200grs. I actually liked the Ruger setup on the Chapuis. As far as being quick removal it required a small 'T' wrench I made or a S&W keychain screwdriver they used to make. Went back to zero perfectly. I believe I would just remove the blocks and mill the thumbnails in the side and mill a cross slot for the Ruger rings. Any GOOD gunsmith should be able to do that for a reasonable amount. I have NOT scoped any doubles other than 9.3's so can't speak with any experience with them.-------- Poor memory,had a Winchester 101 O/U in 30-06 that had factory mounts on it. Shot very well. It was a pivot mount.

Let me add some detail to the excellent post by 400 Nitro and the follow-on by Zimbabwe. Having bought a .350 Rigby No. 2 ex-Australia I had it scoped by adding a WARNE rail and WARNE early version quick detachable rings. The scope was a Leupold compact in 4X. To get proper eye relief the gunsmith put both rings on the front barrel of the scope; in other words, ahead of the turret. He used the back sight as recoil stop using the front ring. No problem with regulation.

Some years later I tried to change to a Leupold Vari-X III. The longer scope enabled me to put the rings on either side of the turret, a good idea for all the reasons we know. Still had the front ring up against the back sight as recoil stop. Problem was the barrels now printed 10 inches apart. I put the 4x compact back on.

Lesson learned: where you put the nodes on which the new mass (of the scope/rings) rest can be vitally important in the regulation equation.

Regards, Tim

I have heard of someone buying a ruger quarter rib and cutting out the ring attach sections, fitting to the chapuis quarter rib, then using ruger rings. I don't recal where I came across the post however it may be another option. I would suggest however that since you have a rifle worth several thousand dollars, spend the money and get the pivot mounts...I think you will be much happier with them in the long run.

Thanks to all for the info. I'll holler at JJ this week and see what he has/recommends. Thanks again fellas.

Showbart- I'll pick her up from McBrides then Call J.J. McBrides ought to be able to do the work. I wouldn't want to hassle you with it. Thanks anyways.