As jeepman has mentioned there are many other ways to end up with a shootable handi barrel. I have done several dozen barrels for handis and other brands of break action rifles / shotguns. I will list some of the ways I have done them and they have all worked fine.
Starting with a stub of about 3 1/2" long, drill / bore or ream the stub thru to a common size then using a tap thread the front side of the stub then turn your barrel to fit.
Doing the same way except with the stub chucked up with the breech end out, Drill, bore , or ream thru then tap the breech and make your barrel to fit. This would work if you are working with a slim profile barrel that does not have enough diameter to blend into the stubs 1.1 " front side diameter. On these I have simply turned a piece of steel with a inside diameter to fit the barrel OD and mate up to the front side of the stub and can be epoxied, soldered or welded in place and then finish turned to blend into the stub and taper forward until it matches the barrel profile.
The method that jeepman and trotterlg have used with the stub bored strait thru with a rim cut at the breech to locate the barrel flush with the breechface of the stub then a nut at the frontside to retain it.
I have done one as a hybrid stub / liner by cutting a 410 barrel off just in front of the barrels forend attachment so as to have a longer stub. With a long piloted drill I drilled thru the chamber and bore and made the long stub with a thru bore of .610 then turned my barrel from the breech end forward to the length of the stub and epoxied the barrel into the stub. After the barrel was turned to make the area where the barrel O D mates the stub the same and finished to where the " joint " was nearly invisible.
I have done about 2 dozen as liner barrels, This method you start with a shotgun barrel then cutoff the muzzle end until there is no choke and the bore is the same full length. Then you just turn the liner barrel from a takeoff barrel to fit the shotguns bore and chamber and with a rim at the breech end to head space it and epoxy it in the shotgun barrel. If you are working with a cartridge with a large head diameter you can drill or bore the chamber of your shotgun barrel first to allow enough wall thickness so you feel safe that there is enough around the chamber end.
I have not done a barrel yet with this method but will someday, Starting with a round barrel blank such as Green Mountain sells with at least 1.125 OD turn the barrel with the same chamber swell diameter of about 1.1" then taper towards the muzzle. Mill a flat about 5/8" wide on the chamber swell with a large dovetail or stepped key that is cut 90 degrees to the bore. Then make the underlug from a piece of 5/8 wide flatstock with a matching key or dovetail and silver solder it to the barrel blank. To keep things simple I would make the extractor from a early style round post H & R ejector and just put a spring in front of it to push the case out about 3/16 when the barrel is opened .
In that way the underlug would not only need a hole drilled and a cross drilled pin to retain the extractor so that way the whole surface area between the underlug and the barrel would be soldered instead of about 50 % of the area if it were to have the 5/16 wide square extractor recess as the factory does them.
There is a member here on GBO that built at least one barrel with nothing more than a drill press, belt sander , and dremel tool, no lathe ! and the barrel was perfectly safe, shootable and accurate so it proves there are many ways to do a barrel.
jedman