9mm J Frame

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montess85

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Hey guys. I was looking into getting my S&w 637 machined for moon clips when I came across a few places that will machine my cylinder to accept 9mm. That would allow me to use moon clips anyways as its required for 9mm but also 9mm is a lot cheaper to shoot. I only have one concern. 38sp+p isnt rated as high as 9mm. How can they do this safely? Is there something I dont know?
 
I advise you to forget about it.
Why? Do you have any experience with J-frame 9mm conversions? My rechambered S&W 360J was done by Mark Hartshorne at Pinnacle High Performance 3 years ago and I haven't had any trouble with it whatsoever, great little gun.

ETA: Here's a link to my original post when I got my gun back from Pinnacle - http://www.thehighroad.org/showthread.php?t=400443

And a range report - http://www.thehighroad.org/showthread.php?t=400717

BTW, the significance of the difference between the .357 bore and .355 bullet are way overblown. In my experience with my gun I've seen no appreciable difference in accuracy from .38's to 9mm's.
 
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If you have a J-Frame .357, go for it.

If it is a older .38 Special, I would not recommend it.

SAAMI Pressure specs:
.38 Spl = 17,000 PSI
.38 +P = 18,500 PSI
9mm = 35,000 PSI
9mm +P = 38,500 PSI

The other thing is, you will have .355" 9mm bullets bouncing around inside .380" chambers and .357" chamber throats trying to get to the barrel's forcing cone in a straight line.

Yes, I know people do it all the time and are overjoyed with the results.
But I also know 75 year old men marry 25 year old woman and are overjoyed with the results for a while too.

The other thing is, how long will it take you to save the $80 have it converted + overnight shipping + insurance both ways on ammo costs differances?

rc
 
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Its a brand new 637....I found a thread on another site where a guy had his 642 converted and he said he hadn't notice a problem with accuracy.....
 
I would suggest a .357mag model because of the pressure BUT you would probably be fine regardless. Honestly, my best advice is just buy some speedloaders and be done with it. It's an airweight J-frame keep it simple.
 
I know, but 9mm would be so much cheaper to shoot and I already own several 9mm pistols and carbines...It would be nice to carry one caliber.....I am going to call them tomorrow and ask for more info....
 
You only have to send in the cylinder, it is much cheaper that sending the whole gun. Also ask when he is doing the next batch as Mark waits until he has a few lined up before he does them.
 
Why? Do you have any experience with J-frame 9mm conversions? My rechambered S&W 360J was done by Mark Hartshorne at Pinnacle High Performance 3 years ago and I haven't had any trouble with it whatsoever, great little gun.

ETA: Here's a link to my original post when I got my gun back from Pinnacle - http://www.thehighroad.org/showthread.php?t=400443

And a range report - http://www.thehighroad.org/showthread.php?t=400717

BTW, the significance of the difference between the .357 bore and .355 bullet are way overblown. In my experience with my gun I've seen no appreciable difference in accuracy from .38's to 9mm's.
I can see this done to ole' six-shot 686 range toy but to light weight carry revolver? Like I said if you want to pay someone to adulterate perfectly good gun don't let me stand in your way.
 
If you want cheap to shoot, keep the 38 special jframe as is, handload clays and light cast lead bullets

$.08 per round-
 
montess85,
Have you visited a S&W forum where there is a lot of discussion on the conversion?
 
I have thought about reloading, but honestly I really dont feel like doing that...LOL....I thought it was kinda cool....As more of a novelty and as a side effect be cheaper that 38spl.....Maybe someday I will look into reloading....I just figured since I was looking into getting it cut for moon clips anyways ,that this would give me my moon clips and have a cheaper more plentiful ammo.....
 
rc
"But I also know 75 year old men marry 25 year old woman and are overjoyed with the results for a while too."


G beat me to it (again), but I do believe that is the best ever response I ever heard on this topic.

Cheap ammo always was the #1 driver of enthusiasm for 9mm revolvers, but there never was anything evil about just buying a nice decent autoloader, and if you shoot more than once in while, you will get the ammo price savings back pretty quick.. even a mostly wheelgun guy like me.

PS
those 75 year old guys probably have reason enough for joy, no matter how short lived
but the 25 year old ladies, probably not

"It would be nice to carry one caliber."
oft said... but why ???
you don't carry ammo, you carry the gun
the gun or mag or speedloader carries the ammo
if you carry a "BUG", just many how reloads do you really feel you need for both primary..plus ?
I never did quite get that
just load up before you never leave home without it, whatever it is
 
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I went the route of having a local 'smith/armorer get me a 9mm J-frame cylinder from S&W. I (slowly and carefully) fitted it up to my Model 637. My practice is done with lighter 9mm handloads, but it's had a couple moon clips' worth of full powered ammo run through it as well. No issues of any kind. I now call it a "Model 937". :)

Of course the original .38 special cylinder can still be used, but I rarely run it that way anymore. Found carrying moon clips to be handier than speedloaders. YMMV and all.
 
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