Shotgun rifling

ATOM

ATOM

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Doing some experiments and would like to get a surplus 12 ga Remington 870 barrel rifled with a special twist rate.

First off, is this possible? If so, who would you recommend?

Thanks.
 
Look for a barrel maker who does cut rifling and you may talk him into such a project. Since its a special situation and would probably require more time to set up it will be more expensive. Google Canadian barrel makers , there are a few that do cut rifling.
 
This sounds like a very expensive experiment... I think the bore of this 'surplus' barrel would be too large in diameter for a 'normal' rifling procedure. You would end up with weird bore dimensions. If anyone will do it...
 
guntech - You may be right, but I've an idea I want to try, something that's been itching for a while. Appreciate your thoughts, though.
 
Can I suggest that you experiment on something like one of the single shot H&R style single barrel guns?

Look up how the guys "Stub" the barrels to install a different tube on the cheap.

Might be a good experimental option for trying out an idea without having to commit to fitting the breech and retaining segments on to a replacement tube, only to have it maybe not work as well as you had hoped.
 
trevj - Thanks for that. Were I starting from dot.go, a single shot would indeed be the way to go, but I already have an 870 and a spare barrel (which I know fits as it is the original).

I know it's possible to rifle 870 barrels as Remington sells them rifled. What I am hoping is that it's possible to rework an existing barrel.

Cheers.
 
From my admittedly limited exposure, I think most rifled barrels are made from noticeably thicker barrels. I would think cutting rifling into an existing smooth bore might be flirting with disaster...




But anyway, what’s your expirament? I’m curious now.
 
kodiakjack - the barrel thickness issue has occurred to me. Obviously it could be a problem. Just brainstorming at this time, trying to improve sabot slug accuracy.

Rifle barrel are thicker as their internal pressure is much higher - 50,000+ PSI vs 10,000. Yet it's possible to launch 1 oz slugs at respectable MV from shotguns.
 
ATOM said:
kodiakjack - the barrel thickness issue has occurred to me. Obviously it could be a problem. Just brainstorming at this time, trying to improve sabot slug accuracy.

Rifle barrel are thicker as their internal pressure is much higher - 50,000+ PSI vs 10,000. Yet it's possible to launch 1 oz slugs at respectable MV from shotguns.
Click to expand...


Yeah I don’t think it would pipe bomb on you, but maybe deteriorate faster... maybe warp along the thinner rifling cuts... just a thought.

So custom rifling to increase sabot accuracy, eh? What kind of custom rifling did you have in mind? An increasing twist rate? An unusual trist rate? More grooves and lands? Less grooves and lands?
 
ATOM said:
trevj - Thanks for that. Were I starting from dot.go, a single shot would indeed be the way to go, but I already have an 870 and a spare barrel (which I know fits as it is the original).

I know it's possible to rifle 870 barrels as Remington sells them rifled. What I am hoping is that it's possible to rework an existing barrel.

Cheers.
Click to expand...

The problem with reworking an existing barrel is that the bore size has already been cut to the larger diameter.

When boring a barrel from scratch, the bore is created smaller, then the rifling grooves are cut out to approx the same diameter as the projectile.

Reworking an existing barrel, gets you rifling grooves that provide you with a really easy path for the gas to escape around your wad, maybe or maybe not to your detriment.

So, when Remington makes the barrel blanks for a rifled barrel, they make them with a smaller bore, to account for the material removed or displaced in the rifling process (if cut, or button rifled) or they size the mandrel that they rifle it on (if forged) to give an end bore size that is accounting for the correct end diameter.

Short version. You could pay to have it done, but it likely isn't going to work all that well. Not as well as buying a barrel from someone that makes them.

Personally, I would consider this a non-starter, as far as projects go. Money and time wasted.

I sorta doubt anyone that actually has the machinery to rifle a barrel would go for it, simply on the basis of that they would expect to end up wearing the blame if it didn't work.
The "Inventor" problem. No matter how bad an idea the Inventor has, when it doesn't work, it always seems to be because the machinist that built the parts was incompetent!
So machinists end up steering clear of Inventors, eh?

So. You have a theory to try.

What is your theory?

Like as not, it isn't a new theory that nobody has tried before. Like as not, someone actually makes the barrel you want, whether it's a fast twist, slow twist, gain twist, etc.
All of which are like to give more satisfaction for the buck spent than pounding money in to the original barrel and ruining it.

There is NO money to be saved by starting from what you have, IMO, unless you are doing all the work yourself.

But if you were doing that, you would not be asking the questions you are. Yeah?


Cheers
Trev
 
Trev - You may be right. On the other hand, I have already considered much of what you are saying and still think I may have something worth investigating. At this stage, it's just research, investigation and discussion.

Flare-stablized slugs have been marketed, using sabots, designed for unrifled barrels. Other sub-cal slugs have been made for rifled barrels, with reasonably good success. Having studied ballistics in school, i think it might be possible to improve in the accuracy seen to date using spin-stablized sub-cal projectiles. The problem is that the rate of spin from the commercially-available barrels is too slow for what I have in mind.

Anyway, I do appreciate your comments.
 
With the experience of doing things with Ron Smith who most know is a cut rifling barrel maker, Id say it can be done. But like most have said it will be dam expensive first off. Due to the fact a single point cutter has to be made to do the job, an it will probably never be used again. Then do to the fact your wanting rifling cut in an existing barrel it would have to be very shallow in order to have any effect which may or may not actually provide the effect you want. The job itself is no different then making any other barrel, basically taking a smooth hole an cutting the requested turn inside it.
At one time many years ago Ron rifled a cannon barrel which shot like a target gun, so anything is possible but be prepared to (anti up) after all experimenting is result of curiosity. I would think you could buy 3 or 4 rifled commercial barrel for the price of this experiment.
The other thing you could look at is building yourself a simple rifling machine an do it yourself experiment........ lots of info on the web ....... you might surprise yourself with what you can do........ But as you might know I am believer in REBAR rifle barrels which I have an they also were thought as a joke...... LOL
have fun.
tom
 
ATOM said:
Trev - You may be right. On the other hand, I have already considered much of what you are saying and still think I may have something worth investigating. At this stage, it's just research, investigation and discussion.

Flare-stablized slugs have been marketed, using sabots, designed for unrifled barrels. Other sub-cal slugs have been made for rifled barrels, with reasonably good success. Having studied ballistics in school, i think it might be possible to improve in the accuracy seen to date using spin-stablized sub-cal projectiles. The problem is that the rate of spin from the commercially-available barrels is too slow for what I have in mind.

Anyway, I do appreciate your comments.
Click to expand...

How sub-caliber do you want to go?

There are already .50 caliber sabot slugs and fast twist barrels available(1-24, IIRC for 12g), there are slower twist rate barrels available for the regular slugs.

Before I spent a bunch on trying to cut something, I would say that a long hard look at what is actually available might be for the best.

Sorta like the old adage about racing, where they ask how fast you can afford to go, how much money do you have to throw at this (plus the potential destruction of your barrel) for the sake of an experiment?

Won't tell ya not to, just that I wouldn't, eh?

The guys that have posted their experiences with Ron Smith reboring their rifle barrels were talking numbers on the order of ~$500 for the job, and that was for rifles in 'normal' calibers. Even at roughly half that, you are getting into the territory where you have more money into an idea than just buying a new barrel is, if you factor in writing off a barrel if it doesn't work when you cut it from your owned one.

Lots of pretty basic sine bar type rifling machine projects documented out there on the web. Again, with the time/money/effort equation though. How much of any do you wish to invest? I already own most of the machine tools I need to make a barrel, but frankly, won't, when there are guys around that can do a good job of it, for less money than I would spend on scrap and tools, trying to get to the end goal of a working firearm. They factor all that scrap, into the price they charge for knowing what they do now, eh.

Cheers
Trev
 
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