Texan shot shells

So a while back I bought some speers colt 45 long shot shells, intending to try them in my 909s.

Well, they are too long to fit in the breech.

Fast forward to yesterday, when I remembered about them while cleaning the new Texan carbine. I decided to see if I could wiggle on in the breech - and I can! The plug needs some slight trimming to fit, but they do fit.

I am wondering if this would be decent for turkeys, with 1 or two shot shells loaded in the breech.

I don't have any lead or bismuth #4 or $6 shot to try out, and wanted to get some opinions before I go and order a 10lb bag or something.

I searched the forum and google, and didn't really find much on using shot shells in the Texan. Anyone?
 
If you want to experiment with the thing, call up AirForce and see if they have a blemished barrel you can buy for cheap. Then, add choke to it by heat shrinking the front. Though I haven't done it, I did read on AGN that the process of doing a choke is simply evenly heating the front portion of the barrel that you want choked and rapidly cooling it to shrink it down a few thousandths of an inch. Alternatively, you could even have a good gunsmith machine the front to add one as well. But that could be getting expensive for an experiment. If it works out for you, AF should give you a barrel, as they will have another new Texan model to sell. 
 
I have a .50 Wingshot. It takes Air Venturi shot cases. Might work for you. I have lots if you want to try them. But I think the cases are only going to hold the shot together for loading. The cases blow apart on firing in my smoothbore. Again, you are left with a donut looking pattern because of the rifling. A reamed out factory barrel would be perfect. Darrell