JNewell
Member
It's not bad at all. It's a relatively heavy all-steel revolver. It's more or less the same as a Model 60 or 37 with +P .38 Special, as posted above.
640 to 940 conversion?
- Thread starter r2d4
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It's not bad at all. It's a relatively heavy all-steel revolver. It's more or less the same as a Model 60 or 37 with +P .38 Special, as posted above.
Interesting thread. I love the idea's put forth. Maybe I can find a beater M60 0r 649 and do a conversion, would hate to tinker with what I have because I like originality.
Remember if you get a crane and cylinder you may luck out on timing and be able to swap cylinders with one screw. Noone will be the wiser.
The replacement crane can be adjusted to the cylinder window with the 940 part on it.
Peter
David Sinko
Member
I took my 940 to the range today and shot some 7.62x25 through it. They actually fit into the cylinder with or without moonclips and will fire, although after two or three rounds the cylinder will lock up. Of course the sub-caliber bullets hit sideways, but if you need it in a pinch it can be done. Those of you with your converted cylinders can add this cartridge to your list and see if it performs better in your reamed cylinders.
Dave Sinko
Dave Sinko
Double-O-Dave
US Veteran
I bought a Model 442 cylinder that had been converted to fire moon clipped .38 Special for my Model 642. I just swapped the cylinders (with the ejector still installed) without any problems. Accuracy is fine, plus I got a "Bubba Pinto" gun out of the deal. I had also heard that swapping cylinders was on a case by case basis as to whether it would work or not. I think mine worked.
Best of luck,
Dave
Is there a chance that I may have to get an additional crane also? FWIW I ordered my cylinders from the factory today. They said they had seven left and there had been several requests if they had any in stock. I thought I would pass that on in case someone here wants one.(or two)
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The 9mm absolutely spanks the .38spl out of a snubby. Somewhere in here are a couple of threads with chrono results from some caliber/load comparisons I did. The most potent .38spl round I had on hand was the Federal 110gr Hydrashok at 873fps out of a S&W 637. By comparison, the slowest 9mm I tested was Magtech 115gr FMJ at 1057fps from a Taurus 905. Big difference.
David Sinko
Member
I have shot the 158 gr. SWC out of the 2" .38 Special at 1100 FPS. The 9x19 can never match that, and I have not seen chronograph results that indicate that the 9x23, .38 Super or .356 TSW can do it either.
Dave Sinko
Dave Sinko
Was that home brewed or a factory load? If that's a factory load I'll carry it in my 3" 586 instead of magnums.
David Sinko
Member
All my velocities were obtained with handloads. There is a thread in the Handloading section of this forum that deals extensively with SR 4756 powder and the .38 Special. I was skeptical at first but then tried some for myself and am now a believer.
If you can shoot 9x23 out of your revolver and you handload, why not try some 158 gr. cast bullets sized .356" while burning Power Pistol? I think that would have the greatest chance of beating the handloaded .38 Special in a 2" barrel.
I have little use for the .357 Magnum and I'd prefer the heavily loaded .38 Special out of a 3" barrel. I love my 940 and in many ways prefer it over my Model 60, but when it comes to power in my experience the .38 Special will always win.
Dave Sinko
If you can shoot 9x23 out of your revolver and you handload, why not try some 158 gr. cast bullets sized .356" while burning Power Pistol? I think that would have the greatest chance of beating the handloaded .38 Special in a 2" barrel.
I have little use for the .357 Magnum and I'd prefer the heavily loaded .38 Special out of a 3" barrel. I love my 940 and in many ways prefer it over my Model 60, but when it comes to power in my experience the .38 Special will always win.
Dave Sinko
safearm
US Veteran
rd,
FWIW, I don't think recoil is much of an issue with the 9mm in the J frame. In both my converted 637 and 940, I shoot GD 124 grain +P. Subjectively, I don't think the 9mm+P has any greater recoil than the .38 Special +P. The 940, with the all steel frame and non-tapered barrel, has less perceived recoil than the 637, but both are easily manageable. I carry Herrett's smooth coco bolo grips with Tyler T-grips on both guns and I don't have a control problem.
I used to carry and shoot .45 ACP all of the time, but arthritis in my hands has made that too uncomfortable. I don't have a problem with the 9mm in either the J frames or a 3913, but then again, I'm not shooting as much as I once did.
FWIW, I don't think recoil is much of an issue with the 9mm in the J frame. In both my converted 637 and 940, I shoot GD 124 grain +P. Subjectively, I don't think the 9mm+P has any greater recoil than the .38 Special +P. The 940, with the all steel frame and non-tapered barrel, has less perceived recoil than the 637, but both are easily manageable. I carry Herrett's smooth coco bolo grips with Tyler T-grips on both guns and I don't have a control problem.
I used to carry and shoot .45 ACP all of the time, but arthritis in my hands has made that too uncomfortable. I don't have a problem with the 9mm in either the J frames or a 3913, but then again, I'm not shooting as much as I once did.
HEADKNOCKER
Member
r2d4 here is a video that shows the installation of the end shake bushings in a S&W, Not a J Frame but the same..
YouTube - Gunsmith - Fix excessive cylinder endshake in S&W revolver
YouTube - Gunsmith - Fix excessive cylinder endshake in S&W revolver
Thanks Headknocker. I can do what he did on the video. Safearm thanks for your imput also. I will have the time next week to see if the cylinders will work on the 640 with no smithing. I will try it on my model 60 also.
HEADKNOCKER
Member
If the cylinder is coming from S&W & never been fit to a revolver it won't just install..
The ratchets teeth will be extra long & the hand will bind on the teeth.. The ratchets spurs will have to be marked & filed down to match your hand..
There's no easy way I know of to do this.
I have heard of a hardened hand that was used to mark the ratchets but have never seen one in person..
The ratchets teeth will be extra long & the hand will bind on the teeth.. The ratchets spurs will have to be marked & filed down to match your hand..
There's no easy way I know of to do this.
I have heard of a hardened hand that was used to mark the ratchets but have never seen one in person..
HEADKNOCKER
Member
No need to change the barrel, It's within .001"..
I don't know who to send you to as most gunsmiths are afraid of caliber convertions as there's a liability issue & alot of 940s have the sticking case problems too, Just because your getting a "NEW" cylinder doesn't mean you'll get a "GOOD" one.. Lets Hope..
I still haven't been to the range with my Airweight convertion yet..
Off to the Gunshow in Cave City KY this morning..
I've got my eyes set to find several different 9mms
Glock 17/19/26, SIG P225/P6
Also always looking for a Clean Model 60 or 640-1 too.
Good Luck with your convertion..
I "MIGHT BE" Interested in fitting a few cylinders being I'm unemployed currently, It would take way longer to do than you could imagine being I've already done one & know what to expect..
Who Knows??
Talk at you Later
Gary/Hk
I don't know who to send you to as most gunsmiths are afraid of caliber convertions as there's a liability issue & alot of 940s have the sticking case problems too, Just because your getting a "NEW" cylinder doesn't mean you'll get a "GOOD" one.. Lets Hope..
I still haven't been to the range with my Airweight convertion yet..
Off to the Gunshow in Cave City KY this morning..
I've got my eyes set to find several different 9mms
Glock 17/19/26, SIG P225/P6
Also always looking for a Clean Model 60 or 640-1 too.
Good Luck with your convertion..
I "MIGHT BE" Interested in fitting a few cylinders being I'm unemployed currently, It would take way longer to do than you could imagine being I've already done one & know what to expect..
Who Knows??
Talk at you Later
Gary/Hk
qballwill
Member
what are your opinions on getting a 38 cylinder reamed for 9mm? I am thinking about getting a beater j frame and sending the cylinder off to get cut. what do you all thing?
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