After I installed the Kirst Konverter on The Outlaw I had a spare percussion cylinder lying around. I decided I might have a go at boring it out for .44 Colt. I turned down the pack of the cylinder so the ratchet would be able to pass through a breech-plate, carefully mounted it in the drill press and had a go with a .450" drill.
Yeah, didn't work- it cut through the bottom of the locking notch. Well poop. Oh well, I wasn't going to do anything with it anyway. I set it aside and forgot about it until I ran across some 9mm/38 barrel liner Linda bought me for projects. I'd bored the cylinder to .450 and the liner had a nominal outside diameter of .440-.445... Hmmm...
I cut a section of barrel liner and hammered it into the cylinder- and it took some serious hammering- but it fit as perfectly as you might want. I bored out the other chambers and inserted liners in them as well. I sweated in a bit of silver solder to secure them and now I had a cylinder lined for .38 or so. Complete with rifling. Not a problem- I just bored them out to 355 and figured I'd ream them for .38 Special. I'd have to wait to lay hands on the reamer but that was no big deal. Then I found out a buddy of mine had a 9x19mm chamber reamer... hmmm... I already have a .38 conversion and the wife shoots a fair bit of 9mm. 'Why yes, Tinker, of course you can borrow my 9mm reamer.' In no time at all I had a Pietta .44 cylinder re-chambered to 9mm. Of course now I needed a gun to make and fit a breech-plate.
Last night the wife had vanished into a book after dinner and I was a bit bored, so I trundled out to the shop. As it happens I do have a Pietta .44 on hand- The Outlaw. I pulled out the Kirst Converter and started, uh, Tinkering. I started with chunk of .326" half-hard spring steel and bored it for the turned-down back of the 9mm cylinder, then cut the back of the plate for a flush-fit to the breech face. I traced around the base of the cylinder and ground the plate round, then flattened one edge to meet up with the frame. Once everything fit up proper I attacked the top with cut-off wheels and a file to relieve it for the hammer. last I cut a loading port in the side. It's now complete but for finishing and works a treat. 2-1/2 hours of work and I had a conversion cylinder ready to mount in a gun. Now all I have to do is somehow work another gun into the budget...
I admit it- I was temped to bore out and line the barrel of The Outlaw, but I'd had to re-dress the forcing cone to fit the Kirst unit. This would leave an unacceptably large cylinder gap with the new cylinder. Thus saved from my poor impulse control I set it aside for now. Next time around I'll make a rebounding firing-pin. While I can't hardly shoot 9mm through a .44 caliber barrel I can test it to see that I get good ignition.
Here's some pics of the cylinder and the unfinished base-plate mounted in The Outlaw- (The loads are dummy rounds)
While I am quite confident that the lined cylinder will handle standard-pressure 9mm loads I think that +P and +P+ loads will be verboten. I doubt they'd actually blow it up but the would at very least wear the gun out in short order. This shouldn't be a problem- whatever gun I mount this in is not going anywhere until my heirs get their hands on it, and I'll leave instructions. Of course whether or not they have the brains to follow them is their lookout.
As it is I plan to work up from very light loads to my standard target loads, which are pretty light. Anyway once I have the firing pin in and working I'm at a standstill until I come across a suitable gun and the money to buy it at the same time. I'll Keep you posted.