Shotgun barrel bending jig... change POI

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rbertalotto
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Shotgun barrel bending jig... change POI

Post by rbertalotto »

Do you have a shotgun that simply does not shoot to POA?

I did and I needed to do something about it!

"Shotgun Barrel Bending to Change Point Of Impact"

A full report is now posted on my web site:

http://www.rvbprecision.com

or directly here:

http://rvbprecision.com/shooting/shotgu ... mpact.html

Image

Hope you enjoy it!
Roy B
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fordwannabe
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Re: Shotgun barrel bending jig... change POI

Post by fordwannabe »

Thank you for sharing that. Please let us know when you do more projects they are interesting. Used your ideas to solve a few issues when we made a takedown levergun.
a Pennsylvanian who has been accused of clinging to my religion and my guns......Good assessment skills.
.45colt
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Re: Shotgun barrel bending jig... change POI

Post by .45colt »

Excellent Job!! I followed Your thread over on Shotgun World, several of the Members there better find a good way to cook Crow , they are going to have some to Eat. :lol: :lol: .
Nath
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Re: Shotgun barrel bending jig... change POI

Post by Nath »

That's very professional.
My arrangements usually involve car scissor jack's and blocks of wood.
Actually my mass and the cut betwixt the turf and plow furrow in the field did it once!

N.
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GunnyMack
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Re: Shotgun barrel bending jig... change POI

Post by GunnyMack »

I applaud your efforts but question why you did not change the pitch of the gun? It's much less work to cut wood or install shims to change POI/POA. unless you are talking left- right changes then stock adjustable butt plate works as well. Or add cast on/off to move it.

Just for the record I had an air rifle with a severe UP bend, I bought it after the owners son wasn't able to get it cocked and the kid let go of the barrel. Being a spring gun the barrel flew out of his hand and slammed closed bending the barrel. While in 'smith school I showed it to my instructor. We can fix it. I took it apart and he proceeded to whack it against a block of babbet until it was within about .003-.005 along its length. Gun still shoot great.
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rbertalotto
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Re: Shotgun barrel bending jig... change POI

Post by rbertalotto »

Thanks for the kind words.....

This shotgun was so far off with everything set neutral that it needed to be bent to simply get it back to 50/50. With the comb all the way up (3/4”). It was ungainly and still only shot 40/60. Bending or custom, offset, choke tubes was the only way to go.

Yes, slamming barrels against tires, bags of lead shot, phone books and the arms of a sofa are all acceptable methods to many gunsmiths to change POI........but I wanted to take a much more controlled method....
Roy B
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GunnyMack
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Re: Shotgun barrel bending jig... change POI

Post by GunnyMack »

Again, a great solution. Before you get to bending that other barrel could you stick it between centers and check how straight it is? I'm curious just how far out it is!

What made you pick the mid point to bend? Was that where it out?
However I still think recutting the pitch would have been easier...
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piller
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Re: Shotgun barrel bending jig... change POI

Post by piller »

A few years ago 86er bent the barrel on my old 870 Wingmaster 20 gauge so that it shot to where my son looks when he mounts the gun. He also put some cast at the stock. My son is right handed and severely left eye dominant. Factory shotguns shoot several feet off to the left for him.
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Old No7
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Re: Shotgun barrel bending jig... change POI

Post by Old No7 »

Wow, that's a neat jig!

My twin brother has 8+ smoothbore fowlers or "smoothies" as he calls them, and his tool to adjust the POI to the point of aim -- since he has no rear sights on any-- is simply this...

Trees.jpg

Just find a "V" notch of the right size between 2 sturdy trees and bend away! :shock:

It does work -- but isn't as elegant a solution as yours though. I've personally seen him outshoot many percussion rifles in competitions -- and he's using a rocklock or "flinchlock" too! :wink:

Old No7
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M. M. Wright
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Re: Shotgun barrel bending jig... change POI

Post by M. M. Wright »

My jig pulls on the point on the barrel where you want the bend instead of pushing as yours does. Gets the job done though. Ran over an 1100 on a pheasant hunt once and bounced my weight on it while it was bridged on a wooden pallet. Straightened right out.

I find crooked or bent barrels less of a challenge than assembling and aligning an old Harley crankshaft. Mount it between centers and use 2 dial indicators and a big lead hammer. It can take all day.
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Old No7
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Re: Shotgun barrel bending jig... change POI

Post by Old No7 »

rbertalotto wrote: Tue Dec 04, 2018 8:42 pm "Shotgun Barrel Bending to Change Point Of Impact"

A full report is now posted on my web site:

http://rvbprecision.com/shooting/shotgu ... mpact.html
Hi Roy. I just took the time to read your full report -- very interesting and well done.

I'll reuse the word I'd posted earlier -- yours is a more elegant (and measurable) tool than the notch in a tree!

Very interesting how you did not see any "concentric rings of light" in the original factory barrel -- while you did afterwards. So I'd agree with your assessment the barrel was likely bent wrong when you got it, and now you've fixed it.

For sure, that was not an inexpensive 11-87 that you started with -- it should have been made right the first time.

So will you send your post to Remington???

Old No7
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rbertalotto
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Re: Shotgun barrel bending jig... change POI

Post by rbertalotto »

Hi #7..... no, I’ll leave Remington alone. They have enough issues to deal with at the moment.
Roy B
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Old No7
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Re: Shotgun barrel bending jig... change POI

Post by Old No7 »

rbertalotto wrote: Thu Dec 06, 2018 8:46 am Hi #7..... no, I’ll leave Remington alone. They have enough issues to deal with at the moment.
I understand...

I'm glad I got my Marlin 336CB/1894CB/1897CB back when it was MARLIN, and my Remington 700 when it was REMINGTON.

Barrels aren't the only things bent or mis-managed there these days..................

Old No7
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Chuck 100 yd
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Re: Shotgun barrel bending jig... change POI

Post by Chuck 100 yd »

Barrel bending is a pretty common practice among trap shooters. So far I have never had the need to bend one.
I once got a .22 barrel from Numrich that had a pretty obvious warp to it and I straightened it and ended up with a great shooting rifle.
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