Converting J frame to shoot 9mm
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ShivasIrons
SWCA Member
The conversion looks super cool. Would make a great winter project...
Reloading with moon clips
I have factory 9mm LCR and a converted Smith 686 that will use 9x23, 38 Super, and 9x19 with moon clips. I suspect it would also use .380 but have not tried it. I still have the original 686 cylinder for 357 & 38 I also own several 9mm autos and handload. When I have a 9mm reload that doesn't feed in my autos, it goes into my box for the converted 686.
I have found that reloading either revolver with moon clips and round ball is much faster than 38 or 357 with speedloaders.
I first figured that out years ago carrying a 1917 with a shortened barrel on duty. A N frame double speedloader pouch would carry 24 rounds of 45 ACP while only 12 rounds of 357 or 38. I still carried a 38 J frame BUG in an ankle holster with a 2x2x2 dump pouch between the speedloader pouch of 45 and my duty holstered 4" 1917.
I have factory 9mm LCR and a converted Smith 686 that will use 9x23, 38 Super, and 9x19 with moon clips. I suspect it would also use .380 but have not tried it. I still have the original 686 cylinder for 357 & 38 I also own several 9mm autos and handload. When I have a 9mm reload that doesn't feed in my autos, it goes into my box for the converted 686.
I have found that reloading either revolver with moon clips and round ball is much faster than 38 or 357 with speedloaders.
I first figured that out years ago carrying a 1917 with a shortened barrel on duty. A N frame double speedloader pouch would carry 24 rounds of 45 ACP while only 12 rounds of 357 or 38. I still carried a 38 J frame BUG in an ankle holster with a 2x2x2 dump pouch between the speedloader pouch of 45 and my duty holstered 4" 1917.
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What cyl?
Why not just buy a 940 or have a 940 cylinder fit to your frame?
jcelect
Were these cylinders made from 38SPL cylinders or custom made cylinders?
Why not just buy a 940 or have a 940 cylinder fit to your frame?
jcelect
Andy Taylor
Member
I first figured that out years ago carrying a 1917 with a shortened barrel on duty. A N frame double speedloader pouch would carry 24 rounds of 45 ACP while only 12 rounds of 357 or 38. I still carried a 38 J frame BUG in an ankle holster with a 2x2x2 dump pouch between the speedloader pouch of 45 and my duty holstered 4" 1917.
Thanks for the tip. I occasionally carry a 625 .45ACP with 2 moon clips in a double case made for K/L frame speed loaders. I've got a double pouch and a single pouch for N frame speed loaders I used back when I carried a 25-5 .45 Colt. Sure enough, they hold twice as many moon clips as speed loaders.
Tex1001
Member
I have 2 of the 940s with rubber boot grips. Recoil with both is sharp. Almost as sharp as my SP101 with 357 mag.
My opinion is that a Ruger LC9 is similar profile (Sort of), larger capacity, and LC9 recoil is much more manageable, to me.
"Were these cylinders made from 38SPL cylinders or custom made cylinders?"
Standard Titanium .38Sp/.357Mag cylinders reamed to 9x19 and cut for moonclip.
"Why not just buy a 940"
940 is heavy. Goal was to reduce weight of 637-2.
"have a 940 cylinder fit to your frame?"
940 cylinder is both heavy and too short to fit the 637-2 window opening.
Standard Titanium .38Sp/.357Mag cylinders reamed to 9x19 and cut for moonclip.
"Why not just buy a 940"
940 is heavy. Goal was to reduce weight of 637-2.
"have a 940 cylinder fit to your frame?"
940 cylinder is both heavy and too short to fit the 637-2 window opening.
malph
Member
How is the accuracy? Acceptable?
They're comparable, at least as reads to muzzle energy.
9mm vs 38 Special | Ballistics 101
Underwood +p's smoke 'em- but I imaginge firing one out of a J frame would be "uncomfortable"
38 Special +P 158 Grain Hard Cast Keith – Underwood Ammo
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nicky4968
Member
FWIW, my friends who own convertible Ruger Blackhawks say the 9 mm in a .357 bore works well if you stick with jacketed bullets. Cast, don't bother.
I imagine the same holds true with this conversion.
I imagine the same holds true with this conversion.
elpac3
Member
I think the conversion would be a consideration if you are shooting competition and want to carry only one caliber ammo.
For self defense purposes, rounds on target are the key regardless of the caliber. As for reloading speed, that will count in competition. In real life carry and shoot situations if you are still shooting after five rounds or six you are in deep S&%t.
My LOD shooting experience were 2 shots and the fight was over.
For self defense purposes, rounds on target are the key regardless of the caliber. As for reloading speed, that will count in competition. In real life carry and shoot situations if you are still shooting after five rounds or six you are in deep S&%t.
My LOD shooting experience were 2 shots and the fight was over.
"Have no background on this conversion but one might think that shooting a round that's .355 out of a bore that's .357 would result in a good bit of blowby past the slu".
Since the Saami spec for .38Sp, .357 Mag, and 9mm land and groove diameter are all identical at .346 and .355, what causes the blowby?
Since the Saami spec for .38Sp, .357 Mag, and 9mm land and groove diameter are all identical at .346 and .355, what causes the blowby?
Been a year since this thread started, so I thought I'd post a follow up.
My 12.5oz 9mm 637-2 J-frame conversions are still by far my favorite carry.
So far, no problems with crimp jump, and the conversions are far more accurate than I am.
My 12.5oz 9mm 637-2 J-frame conversions are still by far my favorite carry.
So far, no problems with crimp jump, and the conversions are far more accurate than I am.
You're reading my mind, again, Joe! I like my 940.
Jim offered a reasonable answer, "weight," but I quit worrying about that when I gave up my M&P 340 for my 640 Pro.
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Stick a .359" in the 9mm and it is very acceptable. Just a matter of a couple of coats of powder and a bake.
Hugo Stiglitz
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My 940 does not like cast lead bullets. They tumble at 7 rds.
Jacketed or plated no problems.
Jacketed or plated no problems.
Aren’t 940 barrels hard if not impossible to find?
roundels
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Actually, you don't need a 940 barrel at all. Years ago I converted a 1992 mfg. no dash 640 from .38 to 9mm with one of the last 940 cylinders the S&W Performance Center had on the shelf and that gun will put 5 rounds into one hole at 7 yards with 3 different loads. The guy who sold me the cylinder told me that the 940 barrels were .357 caliber despite the 9mm rollmark. The only difference was the external contours.
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My experience with shooting 9x19 in a Smith revolver is a mixed bag.
Years ago, Tom the founder of TK Custom came to the ICORE regional, the Wheelgunner's Revenge at Niles, Michigan.
He saw my future wife, a sponsored USPSA Single Stack/Limited shooter, taking a dab into round guns, competing with my 6" 686 that I'd worked over for action pistol competition.
She was fine with the shooting part, of course, but without having put time into reloading she wasn't going to get into the top ten. And, given the amount of practice she devoted to Single Stack, the Comp IIIs weren't going to get the call.
Still, Tom saw potential and sponsored her with a new cylinder and a pile of his excellent 9x19/.38 Super moonclips plus a loader.
Basically, factory 9mm ammunition could not get anywhere near to making the power floor in USPSA, even in a six-inch barrel.
I made some moderate .38 Super loads with SnS 147s but she never did cotton to the whole thing.
I tried some souped-up .38 Supers that made Major power level. I hesitate to think of what the pressure may have been, but the stout 686 didn't seem to mind.
In the end, I got better scores with my .45 ACP revo, which is a lot faster to reload and rather milder to shoot compared to mid-level .357 magnum, so the outfit got put aside.
These days, the converted cylinder goes into the 4" 586 and gets fired mostly with .38 Super; I have quite a supply of the stuff from the USPSA days.
If ever I were to carry it, I'd consider the 9x23 Silvertips I have a small supply of. These 125s exit the blue gun at just over 1500fps. That's serious.
In general, though, getting full power out of the conversion is not usually the case.
In our training business, we did see a number of the Ruger LCR 9s, and many of them did have some crimp-jumping issues with ordinary factory FMJs. This often ties the gun up completely, so if it's a self-defense gun, this would need to verified.
Oddly, we have not seen one of these guns in a class in several years now.
To the point about 9x19 and .38 Special being more or less equal in effectiveness for self defense, or the .38 being less powerful, I'd say that only stands until some Buffalo Bore is located.
His 158gr SWC-HP comes smoking out of my 2" Detective Special at well over 900fps, and in some of my 4" guns comes close to 1100fps. That power level, combined with the highly-effective bullet design, puts just about any 9x19 on the trailer.
One more thing- the quality of the TK work and products is absolutely excellent and a joy to behold. Top notch.
Years ago, Tom the founder of TK Custom came to the ICORE regional, the Wheelgunner's Revenge at Niles, Michigan.
He saw my future wife, a sponsored USPSA Single Stack/Limited shooter, taking a dab into round guns, competing with my 6" 686 that I'd worked over for action pistol competition.
She was fine with the shooting part, of course, but without having put time into reloading she wasn't going to get into the top ten. And, given the amount of practice she devoted to Single Stack, the Comp IIIs weren't going to get the call.
Still, Tom saw potential and sponsored her with a new cylinder and a pile of his excellent 9x19/.38 Super moonclips plus a loader.
Basically, factory 9mm ammunition could not get anywhere near to making the power floor in USPSA, even in a six-inch barrel.
I made some moderate .38 Super loads with SnS 147s but she never did cotton to the whole thing.
I tried some souped-up .38 Supers that made Major power level. I hesitate to think of what the pressure may have been, but the stout 686 didn't seem to mind.
In the end, I got better scores with my .45 ACP revo, which is a lot faster to reload and rather milder to shoot compared to mid-level .357 magnum, so the outfit got put aside.
These days, the converted cylinder goes into the 4" 586 and gets fired mostly with .38 Super; I have quite a supply of the stuff from the USPSA days.
If ever I were to carry it, I'd consider the 9x23 Silvertips I have a small supply of. These 125s exit the blue gun at just over 1500fps. That's serious.
In general, though, getting full power out of the conversion is not usually the case.
In our training business, we did see a number of the Ruger LCR 9s, and many of them did have some crimp-jumping issues with ordinary factory FMJs. This often ties the gun up completely, so if it's a self-defense gun, this would need to verified.
Oddly, we have not seen one of these guns in a class in several years now.
To the point about 9x19 and .38 Special being more or less equal in effectiveness for self defense, or the .38 being less powerful, I'd say that only stands until some Buffalo Bore is located.
His 158gr SWC-HP comes smoking out of my 2" Detective Special at well over 900fps, and in some of my 4" guns comes close to 1100fps. That power level, combined with the highly-effective bullet design, puts just about any 9x19 on the trailer.
One more thing- the quality of the TK work and products is absolutely excellent and a joy to behold. Top notch.
