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View Full Version : want to Paradox a bbl.



Harter66
03-17-2013, 11:35 PM
The paradox bbl isn't a new idea to be sure I've an older shotgun that as it stands is neither valuable nor terribly useful. Its and old JC Higgins w/the "beer can"compensator screw in chokes modified only. W/o the "beer can" its just a cylinder bore w/a rib and no bead. After much reading it seems a tight imp/cyl is about optimum for heavy buck . It only takes a little spin like 1-48-60 for a round ball.

So if I make a mandrill ,generally, .720 tapered to .710 w/4"flats"at .700 ,arbitrarily ,over 4" w/something resembling a 1-48 twist. Could it be placed in the bore and the bbl be shock cooled w/dry ice to form the bbl around the mandrill or should I resort to some more conventional means?

Willbird
03-19-2013, 10:49 AM
The dry ice will not do it for you IMHO. Back when rifled shotgun barrels were as scarce as hens teeth and very expensive to buy an aftermarket I always wanted to make a cast iron lap, maybe along the lines of a marlin microgroove form, and lap rifling in standard 12 gauge smooth bores.

First order of business though will be to slug the bore and see what size it is, and if there is taper, or tight and loose spots, etc. That will give you an idea what you have to work with.

What about making a sleeve with rifling on the inside of it, say .003 smaller on the id than the OD of the shotgun bbl, then heating that up (red warm) and slipping it over the muzzle end, when it cools and shrinks it will close the bore up and you SHOULD have a sort of rifling on the inside.

Also how thick is the muzzle part of the barrel ?? They do make rifled screw in choke tubes, not sure how well they work really.

flounderman
03-19-2013, 12:08 PM
It has been my experience, buckshot works a lot better with choke. If you have any rifling at all, you are going to spin a shot charge. the pattern will be in a ring from my experience shooting a 410 in a trapdoor 45-70. I don't know if you have an adjustable choke or screw in, but if it is a screw in, I would try to find another one and cut rifle it if you want a rifled shotgun. The modified tube would work with steel and could be a good buckshot choke. Every barrel is different. Just have to try it.

Willbird
03-19-2013, 12:23 PM
It has been my experience, buckshot works a lot better with choke. If you have any rifling at all, you are going to spin a shot charge. the pattern will be in a ring from my experience shooting a 410 in a trapdoor 45-70. I don't know if you have an adjustable choke or screw in, but if it is a screw in, I would try to find another one and cut rifle it if you want a rifled shotgun. The modified tube would work with steel and could be a good buckshot choke. Every barrel is different. Just have to try it.

The original paradox guns had a short section of rifling near the muzzle, with the shot charge at full velocity at that point maybe it did not pick up much spin ?? My old 870 police 20" rifle sights (box was marked for slugs and coarse shot) is an IC choke.

Harter66
03-20-2013, 04:07 PM
Well w/this 1 it is a safe bet anything resembling choke is gone. While I might dumb luck into a choke set there is a visible air gap through the "compensator" between the bbl and choke. The bbl is pretty heavy walled but I would not "cut" rifle the whole bbl.

Screw ins are 1 option Brilly makes up tooling kits and chokes in .001 constrictions from back bored 10s down it 410 extra full w/straight and spiraled grooves....... just $450 w/3 chokes. In this age I don't want to buy another gun.

I did see an a post somewhere that a fellow pressed a swaging tool over a bbl to make a polygonial rifle/choke section but it scarred the outside,very ugly. Also this guy has a rib I don't want muck that up.

I guess what I'm after is to create a predictable .002-005 oval or quaded constriction that has a a 1-60 twist.

H&H did 1 that I've seen a write up on. It gave modified patterns w/bird shot and grouped well w/RB. It was is a S by S w/a full choke. I'll look around some more there's bound to be an inexpensive way to do it .

Cap'n Morgan
03-20-2013, 05:40 PM
Make a hardened steel slug with the proper dimensions and twist and shoot it through the Barrel [smilie=1:

Okay, I'm kiddin' here, but I wouldn't be surprised if it actually would work.

Mk42gunner
03-20-2013, 11:01 PM
I don't know how well this would work, but what about finding or making an external choke tube that will match the threads in your adapter, and then rifling it? I don't know if tubes for the Lyman Cutts Compensator will fit or not.

I remember reading several years ago that the original Paradox guns had very slow rifling, 1:120 sticks in my mind. This may or may not have been in an article by Ross Seyfried. I have kind of thought about doing it with an internal choke tube over the years, but havn't gotten around to it yet.

Robert

longbow
03-21-2013, 12:33 AM
There seems to be a variety of opinions or possibly in fact there were a variety of rifling twist for Paradox guns but a 12 ga. round ball only wants about 1:110" or so. Somewhat faster certainly wouldn't hurt but is not required.

I shot a few (30 IITC) 0.735" round ball loads through a rifled Remington 870 and grpoups ran about 2" at 50 yards and that with a flinching punch drunk pilot. I had had a long day of shooting some heavy recoiling guns and finished up shooting 12 ga. slugs! DOH! The gun was light and the recoil pad was just hard rubber so I took a pounding but more to the point, the rifling was quite shallow and ran 1:36" twist. I figured it would be too fast for the round ball especially due to small contact area in the bore but they shot very well.

I have been planning to get around to making a rifling bench with the intention of making a deep. wide grooved choke tube with slow twist of around 1:72" so faster than what a 12 ga. ball needs but slow enough it shouldn't strip when whacking into that tube at top velocity.

Some folks claim good accuracy with modern factory rifled choke tubes and all I can find are quite fast twist so... it looks like the idea is not far fetched and with proper fitting components could work well. If I have a gun with barrel threaded for a choke tube I would have bought one and tried it by now. As it is I am planning to make a muzzle brake Cutts Compensator style and do exactly what Harter66 is thinking of. If I make a rifled choke tube I would go cut rifling though.

Longbow

Harter66
03-23-2013, 11:05 AM
I guess this comes down to giver' a try and see.