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longbow
09-27-2008, 08:46 PM
Has anyone here tried a rifled choke tube and round ball? If so, what sort of accuracy did you get?

I'm thinking bore size ball but a tight fitting ball in a shotcup would qualify too.

I ask because I like the idea of a modern Paradox style gun ~ smoothbore but with rifling in the last few inches of the barrel. This would also make the gun very versatile in that it could be used as a standard shotgun or with buckshot using standard choke tubes and round ball or other slug using the rifled choke tube.

I like bore size balls and slugs like the Dixie Tusker.

I have been working up loads for round ball and various slugs in a smoothbore slug barrel. It got me thinking of the Paradox idea but I think the modern choke tubes are rifled with too fast a twist.

A round ball or "square" slug wants a twist of around 1:110". I think a slow twist of 1:60" or less would do but the current sabot twists are much faster.

I borrowed a rifled slug gun at 1:38" twist and was surprised to find that with a 0.735" ball I got 2" groups at 50 yards ~ with open sights and whilst being slapped stupid by recoil, so it likely could do even better.

I'm thinking that even though the ball did well out of a fast twist it might be too much to ask a ball traveling at 1500+ FPS to pick up the fast twist in a short choke tube without stripping.

I don't have a gun with screw in choke system to try so was curious if anyone else had tried. I have been thinking about building a short rifling rack to make a slow twist choke tube but it is a lot of work if a commercial tube will do the job. I suspect it won't but...

If anyone has any answers please let me know.

Thanks,
Longbow

Dixie Slugs
09-28-2008, 08:07 AM
You are correct about the rifled choke tubes...they are a poor compromise at best. We tested one and it took a strap wreich to pull it from the barrel. Our hard slugs cranked it down very tight when hiiting it at muzzle velocity.
Think about the torque that a hard slug puts on the choke tube at muzzle velocity!
Round balls do work good enough in this fast twist...if they a slightly oversize to give more bearing surface in the rifling...and are hard.
Various people have worked with us to get a slow twsy choke tube...but none have come forth with one yet.
Regards, James

missionary5155
09-28-2008, 09:32 AM
Does anyone have any info about a Barrel company willing to turn out a 1-70 up to lets say 1-100 twist Mossberg 500 barrel to use RB in ? This would simplify the use of RB. Imagine a Gain twist.... Nothing to 1-80 (or so) ...

longbow
09-28-2008, 04:30 PM
James:

You bring up another good point with the torque winding the choke tube tight. A heavy slug roaring own the barrel suddenly running into rifling is going to put an opposite twist on the choke tube. Without a large bearing face to take the load it could bind up real good, maybe even strip the threads.

It wouldn't be so much of a problem with a 1:100 twist but there would still be torque.

What I have been thinking about is a system like the Cutts Compensator using a threaded barrel sleeve, expansion chamber and screw in choke tube with large flange bearing surface. I used to have a Cutts Compensator type choke on an old single shot, I think the choke was made by Pachmyr. I bought it incomplete with threaded barrel adapter and a set of choke tubes. I had to make my own expansion chamber and used stainless steel. I wish I still had it.

Brownells and Midway sell a Cutts but mine was a little different, the choke tubes were inside the expansion chamber like typical barrel mounted thread in choke tubes. I would still need a rifled tube and preferably at 1:60 or slower.

Just a thought. If I ever get to it I will try making a rifling rack. A short one for a choke tube shouldn't be too difficult.

Missionary:

You might try one of the black powder barrel makers to see if they could do a shotgun barrel. Anyone doing round ball twists for .50 cal and up would have equipment to make 1:60 or slower twists. They could tell you if they could hold a shotgun barrel for rifling. If not maybe a blank could be rifled then fit to the Mossberg. That would be getting into custom work though so maybe pricey.

Longbow

shotman
09-29-2008, 01:52 AM
why couldnt you rifle a reg shotgun barrel? the rifleing would not have to be deep if you used a plastic shot cup. The only thing you would have to size the round ball to match the barrel and NO choke just a thought shotman

missionary5155
09-29-2008, 06:25 AM
why couldnt you rifle a reg shotgun barrel? the rifleing would not have to be deep if you used a plastic shot cup. The only thing you would have to size the round ball to match the barrel and NO choke just a thought shotman

Now this is a GOOD thought. There must be a thousand old police cylinder barrels floating about... OR what if you was to get the last 3 inches of a choked barrel rifled to 1-80 or 1-100 ?? now this is a plan !

waksupi
09-29-2008, 07:51 AM
Rifled barrel = higher pressure. Sure you want to do that with a shotgun tube?

Dixie Slugs
09-29-2008, 08:07 AM
Excellent indeed! Now, a cylinder barrel will not work for rifling. By the time you rifled the bore, it would be too large in the grooves.
However, a Full choke barrel would work fine. I even think that was how the original Paradox guns were set up. The average full choke gun has a bore around .729"/.730" and a choke that runs .685"/.690".
If the grooves were cut out at bore diameter......you would have about the same as the original. But, remember the Brits used a hard slug/bullet with a very slow twist rate. A sofr slug/bullet just would not/will not work! The slug/bullet should be at least .730" and "squared" (diameter = length)....as is out Dixie Terminator.
Velocity should be held at what the Brits used with smokeless Cordite...around 1200'/" to 1275'/"...and that's plenty fast enough! You can see that damage a 1250'/" Terminator (.730"-730 gr,) did to a 2000 pound bull on Dixie's webpage.
What we are seeing is a growing interest in full bore loads vs pistipl bullets in a sabot.....at least in states other than Shotgun-Only-States...and that quite a few. The results we have seen on true wild hogs is impressive, as well as deer and other larger game in brush hunting situations.
The cast bullet folks are coming to undestand that a hard cast full bore slug/bullet in shotgun bores are the same as other cast boolits, just bigger indeed!
And it's also just pure fun! I have stated many times that the cast boolit folks are my kind of people indeed!
Regards, James

missionary5155
09-29-2008, 12:18 PM
OOOO KKKKKKK !! Now who can we get to do this rifling ? Waksupi is right about pressure being higher... But then there is gonna be no rifling until the last 3-4 inches... so that should be well beyond any HIGH pressure... And a 1-100 twist should not be any worse than a FULL choke getting whacked with steel shot I would think ???

Dixie Slugs
09-29-2008, 01:31 PM
Let's put pressur into focus indeed! Our Terminator (.730'-730 gr - 1250'/") and Tusker (.727"-600 grs-1500'/'- 1 3/8 oz)) are within the working pressure of 12 ga 3" Mag...tested by Ballistic Research! That's out of a 20" rifled barrel!
A solid does not have the pressure of shot load of equal slug weight/powder weightr, due to the difference in sidewall pressure. The original Paradox pushed a .730-730 gr hard solid at 1200'/" with Cordite.
We have people making speculation of pressure that has not had loads tested in a pressure gun....we do!
Now...an equal weight solid will have no more pressure than a shot load at the chamber and less at the nuzzle....if the powder burn is correct and the weight of powder tested.
There is no reason that a Paradox type load can not be done. It would mean doing a copy of the original rifling design and size....simple! In fact, our presnt Terminator, which is a modern copy of the origianl Paradox slug/bullet, would work. The Paradox barrel (amoothbore plus rifled choke) will produce less presure than the fully rifled barrel in use today. Our Tusker has also been tested in Italy by Pedersoli in their ML double 72. Our Terminator and Tusker have been tested in prototype slow twist rifled choke tubes already. The problem still remains of over-tight tubes after firing..all else worked fine indeed.
What more can I say!
Regards, James @ Dixie Slugs

Molly
09-29-2008, 05:10 PM
Nobody has addressed the vital question raised earlier: Who can we ship a set of choked barrels to and have them rifled?

longbow
09-29-2008, 08:12 PM
Molly:

I don't have an answer yet but I have passed the question on to a BP big bore rifle maker that does slow round ball twist for 20 ga. and 12 ga. rifles. I am not sure whether they will be interested but I thought I would try.

I woud be looking for a section of barrel about 6" to 8" long to make a rifled choke tube Paradox style but I also asked them about rifling a shotgun barrel blank.

I will post when and if I get an answer.

I'm thinking that anyone that has rifling equipment for muzzleloaders with round ball twists should be able to do this but maybe size does matter.

Longbow

missionary5155
09-29-2008, 08:29 PM
I have a thread down in "FRont Stuffers asking for a barrel rifler there...35 peeks but no info. I will post any info here also... Maybe it is Google time

waksupi
09-29-2008, 09:06 PM
Norm Johnson, maybe? He rebores and rifles barrels, and is a cast boolit nut.

Molly
09-29-2008, 09:09 PM
I'm thinking that anyone that has rifling equipment for muzzleloaders with round ball twists should be able to do this but maybe size does matter.

Yeah, you'd think that anyone with a cutter head ought to be able to do the job without a whole lot of trouble. Of course, he might have to make a new twist guide.

longbow
09-30-2008, 12:57 AM
Molly:

These guys do 1:104" twist for 12 ga. round ball muzzleloaders so they have the cutter heads. Other than tolerances it shouldn't be a problem as far as I can see at least for a round barrel blank.

They may not be interested but a barrel is a barrel if they get paid to rifle it. This could also work for Missionary's rifled choke idea too if the cutter was set just shy of the bore diameter for the final cuts. It should just cut the full choke portion similar to the old Paradox guns.

I'll see what they say anyway. Even if they will do it they might want to charge more than I want to pay. In fact that's pretty likely!

Longbow

Dixie Slugs
09-30-2008, 08:33 AM
Interestig and informative indeed! What one needs to do first is to decide just what he wants in these guns. Does he want to try to extend his hunting ranges with a sabot gun...or does he want to setup a "Smashdown" gun for close work on large and/or dangerous game. The two belong in a very different design concept indeed.
Ole' Dixie deals with the "Smashdown" concept! it would be very fine if there was some barrel smith that would wise up to the growing market for "Smashdown" guns, instead getting into the top heavy sabot fad. As these Shotgun-Only-States continue/begin to allow muzzle loading guns to be legal...the sabot thing will drop...just watch it!
But, on the otherhand, there is a growing demand for shotgun bores to be used in woodland hunting conditions where a shot is seldom out to 100 yards!...and most are in spittig distance! The South has always been smoothbore country...and in most cases buckshot hunters. They also like doubles and switch barrel guns. Looking at out order/reorder picture over four years proves that a modern multi-ball load like Trii-Ball is a runaway! These little doubles, with sights and slings,..or a short barrel Remigton 870 is a delight to use in heavy cover!
Regards, James

missionary5155
09-30-2008, 09:36 AM
Greetings DIXIE ! I have to remember that phrase "Smashdown" ... Now that is discriptive !
Another thought... does penetration change between a non spinning projectile and a spinning projectile from a rifled barrel ? I recon with 12 bore it is mute.. but when I get my rifled barrel I will try to compare RB at same velocities and throw in some lead mixes also.

Dixie Slugs
09-30-2008, 10:29 AM
When the testing was done at the John Linebaugh Seminar there was no obvious differece in a spinning bullet and a none spinning bullet if the impact velocity, weight, and caliber were the same. There was a slight increase in penetration if Tusker was fired from a smoothbore vs a rifled barrel due to less friction...but not much!
I will repeat the following that is based on many, many tests:
(1) Tissue Damage is a product of Meplat Area (expanded bullet or non expanding bullet) and Velocity.
(2) Penetration is a product of Sectional Density (not just weight) and Velocity.
The ideal cast bullet is a balance of the two, plus the amount of Recoil! Many want to subsitute Mass (bullet Weight) for Sectional Density, but it just does not work in the long run.
In the Famous (Infamous?) Linebaugh Bone Box....a cast bullet must not be brittle indeed! But, most of you knew all this already, didn't you!
Regards, James

Baron von Trollwhack
09-30-2008, 10:59 AM
Some of you may know that Robert Hoyt makes and relines and rebores barrels. And does lots of custom barrel work for friends shooting with the N-SSA.org. Things like making and specially breeching Whitworth style barrels to drop into a musket type rifle stock & hardware. Lots of 58 and 69 caliber work. Outstanding reputation. He even does gain twist rifling.

Freishutz Shop, Robert A. Hoyt, 700 Fairfield Station Rd. Watsontown, Pa, 1777seven, 570-538-156six. Fall nationals are here now so he will be hard to get for a while.

He would be a good one to speak with on turning serious speculation into a barrel. BvT

Dixie Slugs
09-30-2008, 11:33 AM
I just knew the fellows here would be in the 'Know"! Regards, James

missionary5155
09-30-2008, 05:35 PM
Thanks EVERYONE... I have EMailed a couple people and waiting for answers... LOOKING GOOD !!!

Molly
09-30-2008, 05:49 PM
One other thought gentlemen: Once (if) we have our 12 gauge double chokes rifled out, we're going to need the services of someone cabpable of regulating the point of impact. Or are we planning on using sights for one barrel, and kentucky windage for the second barrel?

Of course, we might install sights on EACH barrel, as is done with some double rifles - I believe the Kodiac BP double is so equipped.

longbow
09-30-2008, 08:23 PM
I'm currently only working with single barrel as it is all I have to play with but if the slow twist rifled choke tube works out (and is affordable) I have considered double barrel too. If the tubes are slightly (and I do mean slightly by only a few thou) eccentric with a locking collar so they could be rotated to change point of impact for each barrel then they should be "tunable".

With a tapered lead in to the choke tube it should make little if any difference to ball or slug and a slow twist should not be a problem for a hardened ball or square slug since it has been proven in the Paradox guns.

True enough, there isn't much room to play with a double due to thin barrels but I think it could be done. Maybe it would have to be shims or thin sleeves or even machining the locking face to allow more rotation to tune but I am pretty sure it could be done.

The outfit I wrote to is Pacific Rifle: http://www.pacificrifle.com/spc.htm

I haven't had a response yet.

There is also October Country who also do 12 ga. rifled ML with 1:104 twist: http://www.octobercountry.com/rifles.php

I haven't tried them yet.

I would guess that a thick walled barrel blank could be rifled full length then cut to choke tube lengths and machined from there. I have a lathe so not a problem for me to do that.

For single barrel I would go the Cutts Compensator style but doubles would have to be thin screw in choke tubes.

I let you know if and when I get a response.

Longbow

missionary5155
10-01-2008, 05:39 AM
I received a reply from THE GUN WORKS and they cannot help with barrel rifling..

Dixie Slugs
10-01-2008, 06:02 AM
I am at a loss as to why it's so hard to get a simple rifling job done on a slow twist choke? I know there are people that can do it! And..It's not that complicated. My good friend, Gregg Sappington, has been putting together custom rifled slug guns well before the present sabot fad. He has done some posting on the Slug Shooting forum of Shotgun Wolrld....but that forum is controlled by a poster that pushes the extra high doller Tar Hunt guns in Shot-Gun-Only states When anyone goes there with some other idea....thay get talked down to like they are Dopes!.
On the otherhand, Ole' Dixe (me and the Dixie forum) caters to the everyday hunter. That is why I really like this Cast Boolit group indeed. It seems like this group just enjoys what they are doing and this forum is very informative indeed!As I said before, I don't want the fellows here to think I am just pushing Dixie products. Rather, I am sold on well designed cast bullets and like to discuss their designs.
Regards, James

missionary5155
10-01-2008, 12:07 PM
Longbow... I have written to OCTOBERCOUNTRY.com... I will post result.

missionary5155
10-01-2008, 12:08 PM
Well I can see if and when we can get some rifling work done we better sign that feller to a contract ! He is gonna be a KEEPER !

Baron von Trollwhack
10-02-2008, 06:42 PM
It would seem to me that rifling. bore/groove, and twist data is historical and could be found. Then a smith to execute the barrel, and one to fit it to a simple platform like a break open shotgun. Then cartridge work, then single barrel repeaters, then the double. Eh? Are fully rifled barrel dimensions not already well known ? BvT

yondering
10-02-2008, 08:04 PM
Just a thought here, but it could be that it's hard to find a rifler because they don't want to try rifling a (relatively) thin wall barrel or choke. Watching my local custom barrel maker (Benchmark Barrels), he cuts the rifling when the barrel is still a 1" round bar (this is for rifle calibers). The barrel profile is not cut until all rifling is complete.
A thin wall of a shotgun barrel or choke may resist the rifling cutter, and distort and maybe cause chatter?

missionary5155
10-02-2008, 08:34 PM
Octobercountry replied they cannot help with this project. They did suggest calling "JOE" at GUNWOKS. I also tried to contact Mossberg... but I could not find any Email/WeB contact menas . They only have a phone # which is not a good idea from here.
Above YONDERING suggested maybe it is a "production problem". Maybe it is more feasable to hunt a 1-100 (or so) barrel linner and "line" a cylinder bore barrel ??

longbow
10-03-2008, 08:04 PM
I still have no response from Pacific Rifle so will try another BP barrel maker or two.

Longbow

missionary5155
10-04-2008, 05:58 AM
If anyone comes across a barrel liner who has slow twist liners in 12 Gauge post that info... may just be simpler to reline a cylinder barrel.