wrong ammo

S

sabre2

New member
When I was at the range today, a shooter a couple of stalls down came over to ask me a question about his ammo. He had a s&w j frame 38sp. He had just shot a cyl. of 38 super and wondered why he could not eject his shells. I think he bought this ammo online. He told me he was looking for +p. Somehow he found 38super and thought that was what that meant. I advised him to take his pistol to a gunsmith.
Now I am curious. How likely is it that he damaged his pistol?
john :eek:
 
Depending on how old his J-frame is it may be just a matter of split cases. Find out the age of the revolver or the model number with the dash number included.
 
majic,
I don't think I'll see that guy again, so I can't get the exact specs on the gun. I was suprised that he was able to shoot them after comparing the two rounds. The super is much shorter than the .38sp. I did not get to look at his spent cases, so I don't know if they were damaged or not.
 
WOW! I am wondering how he ignited 38 Super in a 38 Special? The headspacing must have been out of spec, I would have thought the rounds would have fallen through the cylinder.
 
Actually, I'm surprised he got 'em into the cylinder! I was under the impression that the .38 Super cartridge was a tad "fatter" than the .38 Special. :confused:

Damage could've been done too. The pressures for .38 Super are around the .357 Mag range as I recall. It's a wonder he didn't have a KaBoom. :eek:
 
I just consulted Modern Reloading by Richard Lee.

.38 Special
Over all case length: 1.155"
Rim Diameter: 0.440"
Bullet Diameter: .357"
Max Pressure for 125gr Jacketed Bullet: 16,000 CUP

.38 Super
Over all case length: 0.900"
Rim Diameter: 0.406"
Bullet Diameter: .356"
Max Pressure for 125gr Jacketed Bullet: 32,000 CUP

.357 Magnum
Over all case length: 1.290"
Rim Diameter: 0.440"
Bullet Diameter: .357"
Max Pressure for 125gr Jacketed Bullet: 42,500 CUP
(Most loads listed at 36,000 CUP)

Looking at the diagrams of each cartridge, the .38 Super looks to be a semi-rimless cartridge. Given the similar bullet diameters and assuming similar case wall thickness, the .38 Super should chamber in the revolver cylinder, and have enough of a rim to keep it from falling all the way in, yet not enough rim to provide leverage for extraction.

Looking at the max pressures of each cartridge, the shooter is VERY luck that his revolver didn't explode right in his face. 100% over pressure (essentially a double charge) is a reloader's nightmare. I expect that the fired cartridges over-expanded in the cylinder, and when both shrank back to size, the brass was unable to do so, making them fit super tight. The casing didn't fail, because it is designed for such high pressures, though not for this instance. I would expect that the J-frame was of recent manufacture, and carbon steel or stainless steel.

I would not be surprised if the gunsmith recommended destroying the revolver. If it were my decision, I would do so.
 
If the revolver didn't let go right there, I doubt any serious damage was done to it. Those little J frames are pretty tough, and the 5 shot cylinder keeps the stop slot from bulging, one of the most common failure points on a revolver. I suspect the smaller bullet helped keep the pressure down a bit, too.

Plus, he apparently had fired only 5 rounds, so what he did was essentially proof the gun all over again. As noted, the .38 Super is semi-rimmed and so can be fired in a .38 Special or .357 Magnum revolver; extraction is somewhat iffy, though, due to the small rim.

Those pressure figures are maximum working pressures; most factory rounds will not reach that 32k cup for the .38 Super.

Jim
 
Just for laughs, tried to fit a .38 Super into a 640 (no, not to fire it, just see if the dang thing would even fit). It wouldn't get more that 1/3 of the way into the cylinder...I think you'd have to hammer them in the rest of the way :eek:
 
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