The ultimate freefloat

[Double 30]

Had an idea. take a 12 gauge shotgun barrel , dont cut it off but bore it out as is and insert the new barrel. Leave the outside diameter of the new tube under the bore diameter of the shot barrel.If necessary , you could cut the outer barrel off at the end of the forend and perhaps drill the upper portion of the outer barrel to make cooling vents.In this way the true barrel would be as free floated as a Handi barrel could ever hope to be . The overall effect would be like the old German Gew 88 rifle or the Remington model 8 autoloaders with their barrel jackets.I had the idea of doing this to a 12 gauge smoothbore slug barrel ( if I can find one with the old style sights ). The .45 acp doesnt have the powder capacity to use a barrel much over 8-10 inches and I thought of using a barrel of 10 inches and leaving the rest of the shotgun barrel in place to act as a flash supressor ( of sorts ) and a bonk tube. A bonk tube , for those unfamilar, is used by some 22 rimfire shooters to quite things down alittle when shooting indoors.I got a first hand demo by a gunsmith who fired a high speed 22lr in a .22 smoothbore Remington that from the muzzle looked like a .410. Examination showd the .22 smoothbore portion of the 22 inch barrel was about 12 inches long and the balance was about .410. When he fired it inside a 20'x20' room it was no louder than a modern spring piston air gun.Gave me an idea...A .45ACP would be a dandy home defence and plinking barrel and using the previously mentioned 12 ga smoothbore slug tube I could get one with a properly efficient barrel length ( without going throught the whole short barrel rifle crap) and sights already installed.Most bang for the buck. What do you think? 

[jedman]

Double 30,  You kind of have me confused at the first part of your idea, but if you wanted to put a 45 ACP barrel inside of a 12 ga. barrel that can be done.  First off I don't know if it would be legal with the inner barrel being only 10" long ? I'll leave that to someone more up on firearms law.
You do not need to bore out the 12 ga. barrel to do this. You will need a 45 barrel blank that is a minimum of about 7/8" dia. to start with. Take measurements of the shotgun barrels true bore dia.
the chamber dimentions, forcing cone ect. Turn your barrel blank to .004 to .005 under the diameter of the chamber and bore sizes and leave enough diameter at the breech end of your blank to have a rim like a shotshell, when you get it to fit into your shotgun barrel where it's snug but doesnt need to be pounded or pressed in and stops flush with the breech face of your shotgun barrel your done with that part.  I'll leave it up to you if you want to chamber your blank before or after glueing it in the shotgun barrel. The way I have permanently joined the two barrels together is I use a 2 part epoxy with a 3500 PSI bond strength, clean both barrels to get a good bond , then I take length of threaded rod 1/4 20 or whatever fits your need and tape over the threads so not to scratch your rifling stick it thru the rifle blank and at the breech end use a flat washer and a hex nut and at the muzzle end the same thing but be sure your washer has clearance to go thru the shotgun bore without interference and leave the threaded rod long enough to extend out past the end of your shotgun barrel. Tape up everything on the outside of your shotgun barrel with painters tape to keep from getting epoxy on your bluing or anywhere you don't want it.  With the epoxy I use you have about 15 minutes of working time so have everything right in your mind before gluing.
You will need another flat washer that is larger on the OD than the muzzle end of your shotgun barrel and a hex nut to use to pull the rifle blank into the other barrel when you have the epoxy on it takes that mechanical pull of the threaded rod to squeeze out the excess epoxy and to be sure you get the liner barrel flush at the breech before the epoxy starts setting up.
Thats the process that I have used sucessfully many times, after that I will leave it up to you as to making the extracter / ejector work for you. I hope this helps, but not sure of the legality of it ?
        Jedman

Something I forgot to mention, I coat the outside of the rifle blank and the inside of the shotgun barrel both with the epoxy before joining them. A cleaning rod with a wool bore mop or something similar works for applying it to the bore of the shotgun barrel and a small brush to apply it to the OD of your blank.

[trotterlg]

Look up the 22 Hornet 12 gauge insert I made up for Quick.  Larry

[quickdtoo]

I thought it was in the FAQs, but it wasn't, is now!! Here tis....

Tim

http://www.gboreloaded.com/forums/index.php/topic,160165.msg1098710803.html#msg1098710803

[Double 30]

Jedman, sorry for the confusion.As the the method of measuring legal barrel length is from the muzzle to the breechface , the muzzle of the shotgun barrel would be the muzzle used to determine legal length.I'd have the shotgun barrel's chamber reamed to a consistent diameter and threaded and would modify the extractor to work with the .45 case.I would have the barrel insert turned to be about .050 under the bore measurement of the shotgun barrel.I want it to have no contact foward of the former chamber area.The idea is not to line the barrel in the traditional sense, but to have a barrel insert with the most efficient length for the cartridge.The longer , outer barrel if you will, is there to meet not only minimum barrel length but minimum overall length as well. The insert is not meant to be removed without tools. I think a 2 prong spanner would do nicely. As a home defense tool , its much more intimidating to look at a 12 gauge pointed at you than a .45 ( a smart crook would lay down right now to a properly aimed .22 ). The pistol ctg is fully capable of solving the problem but with less noise and recoil.Another point on the inner barrel length.A company , I believe named Cherry's, used to make aluminum rifled chamber inserts for shotguns to allow them to fire .38Specials, similar to the old Fourtenners. Sometimes I have too much time to think...

[bilmac]

I would worry more about some ATF man calling it a silencing device, I think the defination of them is pretty loose. But then sub caliber adapters have been around for a long time.

[jeepmann1948]

Check out this site :
http://www.mcace.com/shotguninserts.htm
 They make sorta what you are talking about

[jedman]

Got the idea now,   I think.   Jed