Cas City Forum Hall & CAS-L
Special Interests - Groups & Societies => STORM => Topic started by: Tinker Pearce on September 12, 2017, 09:14:23 AM
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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.
(https://i.imgur.com/gCmeqxj.jpg)
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)
(https://i.imgur.com/VnmRkFR.jpg)
(https://i.imgur.com/IX4eR2i.jpg)
(https://i.imgur.com/qyZHgO3.jpg)
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.
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Greetings My Good Tinker
I would advise extreme caution going forward: The SAAMI pressure limit for the 9×19mm Parabellum is set at 241.32 MPa (35,001 psi) piezo pressure. That is more than double .38 spcl SAAMI (17,000 psi ) and right at .357 magnum ( 35,000 psi) .
Few people consider the Italian cylinders and open tops capable of handling .357 magnum, whether lined or not.
In general advisable pressures are ~ .38 spcl or less.
yhs
prof marvel
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Use the 9mm brass with .38S&W load data?
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here is a chart of SAAMI pressure specs:
http://www.handloads.com/misc/saami.htm
we can see that even .380 loads are excessive - 380 ACP 21,500psi
so any load that would actually operate a 9mm no matter how light, is probably too much.
And jacketed bullets "generally" increase pressure over lead bullets.
Use the 9mm brass with .38S&W load data?
There ya go! 38 S&W 14,500psi. Slow powder, lead bullets. Kabooms are bad things.
Even with the thick chamber walls, keeping things under 17,000 psi will be more likely to keep fingers, eyes, and cylinders intact
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Pretty cool. I just saw a B-Western shooter (Alamo Andy) this weekend who had a Marlin converted to 9mm. Would make a good mate for your pistola!
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As is said in the post I will start with very light loads and work up- 'trust but verify' and all of that. The goal is to get up to my standard target load, which is quite light and does use lead bullets. I will however stop short of that if need be; .38 S&W ballistics would suit me just fine. The jacketed bullets pictured were for a modern 9mm revolver; I should have made it clear that I was not intending to use these in whatever gun this cylinder might wind up in. I just incautiously threw up the first first picture of the rounds I came across.
I think it is time for a disclaimer- don't try this at home! While I may be willing to bet my safety on my knowledge and skill I am just some guy on the internet, and you should trust neither your health nor safety on my word! Watch, comment and enjoy but do not let my opinions over-rule your knowledge and common sense.
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Greetings Tinker -
By now you have probably noticed a trend in my missives , to wit:
TRY NOT TO HAVE A KABOOM.
Do not take it too personally, as I do this to anyone who might attempt to exceed 20,000 psi in a pre-1900 design.
It is the curse of the "retired engineer who was intimitally intimermitintly overly invovled in catastrophic failure
analysis!
Ask me sometime about the topics of "Shaped Charges and Chamber Designs", "Black Powder Pressure Wavefront Analysis as it applies to Naval Guns", "The Standing Wave Harmonic in Muzzleloading Rifles", "Detonation in Black and Smokeless Firearms", and "Pressure Changes in Smokeless Cartridges as a result of Variations in Volume and Crimp"
The physics will make ones head spin and the Kabooms can be amazing ... and sometimes ( is in "detonation" ) the Kabooms
can be difficult if not impossible to replicate under lab conditions...
I too tried drilling out a .44 C&B cylinder (in my case an old junk remmington 1858 cylinder) and also broke thru the notches :-(
I had considered lining with tubing and chambering for .38 spcl, but I like your use of barrrel liner better :-)
please keep posting !
yhs
prof marvel
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No worries Professor- I know it's all coming from a good place. I'll try hard not to KABOOM.
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Total waste of time and of a gun capable of shooting the fine 44 Colt IMO.
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Total waste of time and of a gun capable of shooting the fine 44 Colt IMO.
I'd agree if I hadn't bored through the bottom of the cylinder notches. I figure it's not a waste of time when the option is throwing the cylinder away! ;D
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Well ya that does shed a little different light on it, but I'd consider what Prof Marvel said about the pressure factor. Loading real low is an option as you don't have to have enough zip as in a regular 9mm pistol to operate the slide.
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Total waste of time and of a gun capable of shooting the fine 44 Colt IMO.
Why, that's all right CC ! It's Tinker's time and only a cylinder swap :-)
You should see the sheit crap incredible inventions that I have created but have never had the courage to inflict upon the outside world, many of which are operational and functioning but remained stuck in "prototype mode" until I can get around to building the final version :(
yhs
prof marvel :(
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We would like to see a Video of shooting the finished product !
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We would like to see a Video of shooting the finished product !
That seems a likely thing- but first I need to find a suitable donor gun!