S & W 640 in 38 Super
Not a typo, however the gun is obviously not factory original.
At a recent gun store visit I saw an S & W Model 640 that had been reworked to accept 38 Super. Nicely done, the cylinder was modified to take full moon clips and the barrel Magnaported - I had to look over the gun a few times to see what the heck was different about it. Whoever did the work left the factory finish as is, the gun looks new and never fired - maybe that's a hint ....[:o)]
Nice execution aside, will a converted J frame S & W 38 Special handle the 38 Super cartridge? I understand I can load down, basically drop to 38 ACP levels, but that wouldn't be much fun all the time.
I like odd guns, but I don't like guns that turn into hand grenades.
At a recent gun store visit I saw an S & W Model 640 that had been reworked to accept 38 Super. Nicely done, the cylinder was modified to take full moon clips and the barrel Magnaported - I had to look over the gun a few times to see what the heck was different about it. Whoever did the work left the factory finish as is, the gun looks new and never fired - maybe that's a hint ....[:o)]
Nice execution aside, will a converted J frame S & W 38 Special handle the 38 Super cartridge? I understand I can load down, basically drop to 38 ACP levels, but that wouldn't be much fun all the time.
I like odd guns, but I don't like guns that turn into hand grenades.
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The 640-1 version, was revised to take .357 Mag., circa mid 90's. If it will handle .357, don't see it having any problem with .38 Super.
Even the earlier 640, was rated for +P ammo. I don't see it selfdestructing with .38 Super. It might stress the innards, with a steady diet of .38 Supers. Not turn into a hand grenade, though.0 -
quote:Originally posted by rufe-snow
The 640-1 version, was revised to take .357 Mag., circa mid 90's. If it will handle .357, don't see it having any problem with .38 Super.
Even the earlier 640, was rated for +P ammo. I don't see it selfdestructing with .38 Super. It might stress the innards, with a steady diet of .38 Supers. Not turn into a hand grenade, though.
Correct me if I'm wrong but 38 Special is rated @ 20K psi, the 38 Super is rated @ 36K psi - 357 is rated @ 35K psi.0 -
http://www.handloads.com/misc/saami.htm
I have shot j frame in 357's and they are not all that pleasant to shoot. If it was mine I wouldn't be loading at the top end.0 -
The "J frame" & "J frame magnum" are two completely different frames. I would expect the .38 Super conversion to be durable on the magnum frame, but I would stand behind a tree & use a string to pull the trigger on a conversion made on the .38 Special frame.
But, this seems to me to be the solution to a non-existent problem. Considering the low cost, versatility, & universal availability of .38 Spec/.357 mag ammo, WHY would anyone convert a revolver to .38 Super?
Neal0 -
The .38 Super is semi-rimmed and will chamber and fire in a .38 Special or .357 Magnum cylinder without moon clips or modification. In my younger, more foolish days, I did just that, many times. 0 -
quote:Originally posted by dfletcher
Not a typo, however the gun is obviously not factory original.
At a recent gun store visit I saw an S & W Model 640 that had been reworked to accept 38 Super. Nicely done, the cylinder was modified to take full moon clips and the barrel Magnaported - I had to look over the gun a few times to see what the heck was different about it. Whoever did the work left the factory finish as is, the gun looks new and never fired - maybe that's a hint ....[:o)]
Nice execution aside, will a converted J frame S & W 38 Special handle the 38 Super cartridge? I understand I can load down, basically drop to 38 ACP levels, but that wouldn't be much fun all the time.
I like odd guns, but I don't like guns that turn into hand grenades.
See here (scroll down):
http://www.pinnacle-guns.com/revolver.asp
I think there is a reasonable chance that this particular gun was converted by that outfit, and if you have the serial #, maybe you could contact them and see if they did the work.
To answer the question, .38 super runs at a max pressure of 36500 PSI, .357 magnum at 35000 PSI. If the gun is rated for 357 magnum (and most Smith 640s are now), it should be OK with .38 Super.
I'd add that the gunsmiths who do these conversions generally aren't complete idiots. Anyone who is capable of doing the moonclip conversion and barrel porting almost by definition is aware of the issues in doing the conversion, and they're not going to create a conversion that is intrinically unsafe, if only because that potentially makes THEM liable. Sight unseen, I'd bet cash money that this gun is built on a .357 magnum-type (not older .38) frame, because that's the only way this conversion makes sense.
Can "ordinary" .38 special J-frames handle .357 magnum like pressures? The answer (from what I've heard. . .I've never tried it and am not going to) is yes, they won't just "grenade". . .*BUT*. . .they won't last long. J frame .38s with .357 magnum like rounds are subject to cracking of the forcing cones, and timing issues. I wouldn't try to build nor buy a gun like this.
In terms of firing *quality*. . .eh. . .I don't think .357 from an *all steel* J frame, with full sized rubber grips is all that bad. Yes, there recoil is brisk, though there is also quite a bit more blast and fire! My issue with this is just that the typical 2.25" .357 snubnose barrel significantly gimps the ballistics of the round. While you do get better performance than .38+P (typically another 50-75 fps), IMO, that's not enough to justify the increased cost, recoil, blast, and flash with .357. I think you need to have at least 3" of barrel before .357 starts to make sense, and longer is better yet. I doubt .38 super is much different.
Bottom line for me, while the gun itself should be safe to fire, I just don't think a 2" snubnose .38 super is all that useful or interesting. Expected ballistic advantage over just .38+P isn't enough (IMO) to justify it.
Assuming this thing can accept 9mm luger (and it probably can), that would be more interesting to me, since 9mm luger ammo is more powerful than .38+P, but cheaper, and I have other 9mm guns that would make this type of ammo compatibility a plus.
Edit, responding to above:
quote:Originally posted by nunn
The .38 Super is semi-rimmed and will chamber and fire in a .38 Special or .357 Magnum cylinder without moon clips or modification. In my younger, more foolish days, I did just that, many times.
Yes, you "can" do this, with the caveat about firing 357 pressure rounds in .38 special revolvers mentioned above.
Also, tolerances are such that you can't slip a 38 super in every .38/.357 gun. There are certain guns/factory brass where a .38 super won't fit into the chamber.
I think the real issue here is that the 38 super semi-rims can get caught with some ejector stars, potentially causing issues in removing the rounds. Some guns will effectively run stock 38 super fine, but they'll get stuck in others, and having a stuck spent cartridge in your revolver that you can't easily remove with your fingers might cause a problem!
So that's one big reason why people use moon clips here. As above, the other is that if the gun is properly converted, you may be able to use 9mm luger and other 9mm type semi-auto cartridges in addition to .38 super.
I wouldn't "push" a J-frame type gun with 9x23 Winchester (L/N frame guns would be more realistic), but the ability to use 9mm largo or that sort of thing might be nice.0 -
I had a fellow officer get away with shooting .351 Winchester Self-Loading in his Python. Didn't make it a good idea, just because it could be done. Mid-velocity .357 Mag in a "J" frame are all my tired old hands can take. I don't see an up-side to this conversion. 0 -
Thanks for the responses and possible contact info.
I'll double check the frame & barrel markings but am pretty certain it's a 38 Special framed J frame. Definitely no lugged barrel. Handgun recoil doesn't bother me. I've gotten used to the Scandium 29, a 22 oz Taurus 41 Magnum along with a bunch of Encore big bore pistols and Bond derringer. An all steel J frame will pop, I know, but not all that bad.
This week I'm picking up the Marlin 336 I started paperwork on last week, I suppose I'm leaning towards "357 OK, 38 Special no go".0
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