.38 Super Out of the 9mm Barrel of a Blackhawk .357 Mag/9mm Covertible

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JBP

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I had a .38 Super barrel converted from a 9mm for my TC Contender which got me thinking about the plausibility of using the 9mm barrel of my Blackhawk to handle .38 Super.

Any thoughts?
 

NikA

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There should be no issues pressure-wise, but if I recall correctly a .38 Super chamber won't quite clean up a 9x19mm due to the greater taper of the 9mm. A better (more costly) approach might be a custom cylinder.

Factory ammo will have undersized bullets for the .357 groove diameter, just like the 9mm.
 

JBP

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There should be no issues pressure-wise, but if I recall correctly a .38 Super chamber won't quite clean up a 9x19mm due to the greater taper of the 9mm. A better (more costly) approach might be a custom cylinder.

Factory ammo will have undersized bullets for the .357 groove diameter, just like the 9mm.
I already have this on my TC barrel so it would be somewhat redundant except that I would have 6 rather than 5 shots. I guess I'll just put a round into the 9mm cylinder and see if it's doable.
 

BearBiologist

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There should be no issues pressure-wise, but if I recall correctly a .38 Super chamber won't quite clean up a 9x19mm due to the greater taper of the 9mm. A better (more costly) approach might be a custom cylinder.

Factory ammo will have undersized bullets for the .357 groove diameter, just like the 9mm.
I had a 38-40 cylinder made to match up with a Colt barrel for a custom Vaquero I put together. Took forever and a day but Tyler was able to do it.
 

contender

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Due to the bore diameter of a Blackhawk built to handle .358 bullets,, followed by the often discussed accuracy issues (especially at longer ranges,) of using 9mm vs .357 ammo,, I'd have to ask "Why?" A .38 Super will be using a smaller diameter bullet,, and would be fine at shorter ranges. But at distance,, the accuracy issue arises.
Next is the power level. A .357 Mag develops more power or can be loaded to match .38 Super levels easily.
So I guess is my question of why comes down to the practicality of doing it AND spending the money to do so. .38 Super brass isn't as common as 9mm, .38 Spl, or .357 Mag. What good can a .38 Super be used for in the field or just on the range, that a .357 can't be used for?

And yes,, I know, I know,, some people just want "something different" or or such reasons.

I PERSONALLY prefer to shoot at longer distances,, accurately,, and spend my money & time being a better shooter using easily available ammo & components. By not spending the money on such a custom,, I can spend it on more components,, followed by more range time & less time in the shop tinkering. JMO,, and just like people,, everybody has one & often they just smell a bit. :D
 

JBP

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Due to the bore diameter of a Blackhawk built to handle .358 bullets,, followed by the often discussed accuracy issues (especially at longer ranges,) of using 9mm vs .357 ammo,, I'd have to ask "Why?" A .38 Super will be using a smaller diameter bullet,, and would be fine at shorter ranges. But at distance,, the accuracy issue arises.
Next is the power level. A .357 Mag develops more power or can be loaded to match .38 Super levels easily.
So I guess is my question of why comes down to the practicality of doing it AND spending the money to do so. .38 Super brass isn't as common as 9mm, .38 Spl, or .357 Mag. What good can a .38 Super be used for in the field or just on the range, that a .357 can't be used for?

And yes,, I know, I know,, some people just want "something different" or or such reasons.

I PERSONALLY prefer to shoot at longer distances,, accurately,, and spend my money & time being a better shooter using easily available ammo & components. By not spending the money on such a custom,, I can spend it on more components,, followed by more range time & less time in the shop tinkering. JMO,, and just like people,, everybody has one & often they just smell a bit. :D
This would be just for indoor range shooting and since I have the Contender and a Colt 1911 ammo is not any problem. I never even considered doing it before someone posted about the .357/9mm convertible. I rarely use the 9mm cylinder as I have 4 9mm pistols.
 

contender

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Ok, indoor range shooting. That usually means a distance of about 25 yds or less. Understood.
Next would be the expense of doing it. And while you may enjoy it,, down the road,, you (or your heirs, or whatever,) may have issues trying to sell it or even worse,, face an upset person THINKING it was a 9mm cylinder. We are all just temporary custodians of our possessions. I'd not pay ANY premium for such a cylinder if I were buying a gun like that. But a gun that's being sold as a convertible, as it left the factory that way would command a premium. And I like to think that the gun's I've purchased, that I got used,, were well cared for & the previous owner appreciated them as much as I do now. And I would like to think my kids & others down the road will appreciate them once they leave my possession.

Luckily,, I do not think there would be a safety issue (pressures etc,) in such a conversion.

But it's your gun, your money & your desires. It's NOT,,, and I repeat this,, NOT up to me to make that type of decision.
 

JBP

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Ok, indoor range shooting. That usually means a distance of about 25 yds or less. Understood.
Next would be the expense of doing it. And while you may enjoy it,, down the road,, you (or your heirs, or whatever,) may have issues trying to sell it or even worse,, face an upset person THINKING it was a 9mm cylinder. We are all just temporary custodians of our possessions. I'd not pay ANY premium for such a cylinder if I were buying a gun like that. But a gun that's being sold as a convertible, as it left the factory that way would command a premium. And I like to think that the gun's I've purchased, that I got used,, were well cared for & the previous owner appreciated them as much as I do now. And I would like to think my kids & others down the road will appreciate them once they leave my possession.

Luckily,, I do not think there would be a safety issue (pressures etc,) in such a conversion.

But it's your gun, your money & your desires. It's NOT,,, and I repeat this,, NOT up to me to make that type of decision.
I wasn't thinking of making a cylinder conversion. I have already done that with my Contender and the barrel is marked as a .38 Super.
Not that I in any way advocate this but a lot of .357 cylinders will chamber and shoot .38Super just fine.
You are right and I never considered this until I watched Paul Harrell's YouTube video yesterday. It depended on the combination of revolver and ammo. When he chronoed his S&W 686 .38 Super came in between .357 Magnum and .38 Spl. He tested 6 revolvers (none a Blackhawk) and 6 boxes of ammo.
 

NikA

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I wasn't thinking of making a cylinder conversion. I have already done that with my Contender and the barrel is marked as a .38 Super.
A bit baffled by this statement, maybe it makes sense if you're talking about a CHAMBER conversion. TC Contender doesn't have a cylinder, chamber is located directly in the barrel portion of the firearm similar to a semiautomatic pistol. For a revolver, the first piece that would need to be modified is the (chambers in the) cylinder, followed by the barrel if changing the bore/groove size of the barrel is desired for the conversion.
 

JBP

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A bit baffled by this statement, maybe it makes sense if you're talking about a CHAMBER conversion. TC Contender doesn't have a cylinder, chamber is located directly in the barrel portion of the firearm similar to a semiautomatic pistol. For a revolver, the first piece that would need to be modified is the (chambers in the) cylinder, followed by the barrel if changing the bore/groove size of the barrel is desired for the conversion.
It was a barrel conversion.
 

contender

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I guess I too was confused. When I read your posts,, the implication was to use the 9mm cylinder to shoot .38 Super. Your first post says "barrel" and your second post says cylinder & giving you "6 rather than 5 shots."
A 9mm headspaces on the case mouth, and the .38 super is longer than 9mm. So MY assumption was you were discussing modifying the 9mm cylinder.
 
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yes, the "chamber " would have to be changed whether in the 'cylinder' or a fixed barrel....Ruger single actions "headspace" on the mouth of the case, ala 9mm, 10mm, 45 acp, etc.........Double action guns need "moon clips" to retain the cartridge for head space........ lots of different calibers in the :"Like" can be shot in either, for example how many 'rimmed' cases can be shot out of a 38/357 mag.......

".....and so it goes....." Wil Terry RIP ;):cool::rolleyes:
 

JCK

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The problem with a 9mm to .38Super is the case of the 9mm is "fatter" ahead of the extractor groove.
The .38Super originally headspaced on the rim in early Colt barrels. This caused accuracy issues. The case head on the 9mm is the same as the rimmed .38Super, so will allow excessive case expansion and possibly case rupture if the .38Super is fired in the rethroated 9mm. BAD !!!

The Ruger barrel is a nominal .357". So are MANY 9mm barrels. Smith &Wesson 9mm barrels are nominal.357" and Beretta and Taurus run .358-.360" !!! So the barrel's no problem.
For many years I sized my 9mm cast bullets to .356". I found.357" to be even better.
If you reload, you can load the .358" bullets in the .38Super. The nominal bore diameter of old .38Super was .356"

IMO, the only reason to have a .357/9mm conversion is to be able to shoot cheap 9mm factory loads if you don't reload..Otherwise just shoot .38/.357mag.
 
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