Stumbled on an EAA kit to convert a 12 ga shotgun to 45/70 via a barrel insert. I've wanted to do this to a Russian TOZ-66 I've had for thirty years This is a 12 ga dbl with 20" bbls and exposed hammers on a Greener action. I was going to buy two barrels and machine them to fit the barrels, but this is even better, it's actually made to fit their double barrel gun with screw in chokes, but as the inserts stick out the 20" bbls by about 3/4", I can just have two bushings made to fit under the barrel nuts to secure them in the barrels of the TOZ. I stumbled on one kit on Gunbroker.com for $100, the seller informed me that EAA still had the kits listed on their website. Went there an found another kit for $159 to do the other barrel. Can't wait to finish this project.

How do you intend to regulate the barrels? At what distance?
Pete.

__________________
"Only hunting and mountain climbing are sports. The rest are just games."

Double barrel shotgun barrels converge at about 40-60 yards.

The 45-70 inserts can be regulated by varing the powder charge and bullet weight. If the inserts are removed or turned in the bores the they have to be reregulated.

Your not looking at a long range rifle here, 100 yards would be a very long shot.

The forward bushings are offset drilled so that you can regulate the point of impact. But like jaguar stated, this is going to be a short range weapon anyway. Wasn't planning on doing any 1000 yard silhouette shooting with this gun.

Please note that MCA Sports have rifle inserts for shotguns. www.mcace.com

The reason that I asked about regulation was that I had little success doing it. I was using MCA barrel inserts - the longer barreled version, not the chamber adapters, and a lighter cartridge (.45 ACP).
When you write that regulation can be done by varying the load, do you mean that each barrel will have a load that will allow it to shoot to the same POA as the other or are you referring to the traditional regulation where both.barrels will shoot a particular load to the same POA?
I looked at the EAA website and could not find the item. Can you supply a link?
Thanks.
Pete

__________________
"Only hunting and mountain climbing are sports. The rest are just games."

Go back to the EAA website, click on "Shop", then click on "parts", then at the bottom of the list, you'll see"EAA side by side rifle barrel inserts" As I said before, their kit is made to fit their SXS double that has 20" bbls and screw in chokes, but after getting this kit in, it doesn't look all that hard to adapt it to any SXS with 20" bbls, all it'll take is to machine their barrel bushings to do it. "Regulation" meant that you could tailor the velocity of the load to hit a certain point of aim to match the sights on the gun. (elevation) In terms of windage, regulating the barrels meant altering them to get them to hit as close as possible at a certain range, that's why SXS double rifles were/are so expensive, it took a master craftsman many hours of work when asssembling the barrels (brazing or welding them together) to come out with a finished product that attained those goals. Those old doubles also had multiple flip up rear sights to give the shooter correct sights for various ranges. It's far easier with this kit using offset bushings to get the point of aim of the two barrels regulated where you want them. I'll never be able to afford most of the real double rifles, this is just an inexpensive way to get what I want and give me more use out of this sxs shotgun I rarely shoot without it. Actually I was toying with doing this to a wildcat caliber based on cut down 300 win mag and 7 mm rem mag belted brass, cutting them back to the forward edge of the shoulder, then opening the shoulder out to seat 458 bullets. At one time I wanted to do this but chambering it to 50-140. The 458 would allow me to use up the couple hundred (if not more) rounds of range brass I've been saving in those two calibers. Maybe I'll just sell that stuff now.

What meant is the same load for each barrel. Not different loads for each barrel, that would be nightmare.

British double rifles were regulated for a set load for both barrels, i.e.
600grain bullet and xxx grains of cordite. Today owners of those rifles are using modern smokeless powders from our suppliers and have to adjust the loading so the gun will shoot the same point of impact.

That's basically what I said. It's just as hard to achieve the same point of impact for the same loading from two barrels. It's actually harder to do that to get a rifle to get the tiny groups that some try for in a single barreled rifle.

Ok, got the 45/70 barrel kit in a few weeks ago, got around to installing them in my TOZ-66 Russian made (late 70's) 12 ga. This is a Greener action gun. I ordered what I thought was a single barrel kit from EAA, but they sent two barrel kits and charged me for one. Maybe they figured to get rid of stock that wasn't moving ? That worked out fine as the single barrel I'd bought off a GunBroker.com auction was missing the extractor and they no longer (EAA) sell the individual parts. The kit is made for their doubles with screw in chokes so it was up to me to find a bushing to fit between the barrel nuts and the barrels. I found the pictured bushings in my shop, they're big block Ford head bolt block bushings, and while they don't look kosher, they do work for the purpose of test firing. I'm gonna have my Brother in law machine two of the EAA bushings to fit my barrels or make new ones from steel. I fired several loads, all handloaded that are hotter than the low powered factory loads available for std 45/70's. Everything went fine, accuracy at 100 yds leaves a lot to be desired, especially since there's no sights other than the single bead up front and the barrels aren't regulated (that will change with the new bushings) I hit the backstop though. I shot some black powder loads (410 gr bullits) some tri ball loads (three 457 cal round balls over 29 grs of IMR 4198 ) Some 520 gr FNGC ( RCBS bullet over 41 grs of AA2015) and some 410 gr FNGC (RCBS bullet over 50 grs W-748) The 520's were clocked out of my 1886 Browning at 1550 fps (26" bbl) and the 410's are at 1600 out of the 1886. Overall I was thrilled with the result, even though the accuracy isn't there (yet) I've ordered a set of sights from Midway to install on the gun, next will be getting the bushings made.

Attached Thumbnails

         

OK, got the sights installed now. Next are the bushings and getting the sights dialed in.

Attached Thumbnails