9mm GP100 "conversion cylinder"?

[BigBlock1]

Been thinking about buying a .357 Blackhawk convertible, but I want one in stainless...those are hard to find/custom. I'm wondering if the same sort of thing might be possible for the GP100? Having an extra cylinder converted by a gunsmith for 9mm, and fit to the gun. GP100s are so easy to take apart and pull the cylinder.

Would this work? It all sounds too easy. Has anybody tried before? I seem to remember reading something about 9mm GP100s, no?

I'm not a particular fan of the 9mm, but the recent ammo supply has me really liking the idea of a gun that can shoot 3 different and most common rounds. Plus it's slightly cheaper for plinkin'...

 

[epj]

I guess the worst part would be the .355 bullet rattling down the .357 bore. Seriously, I think many guns that have a dual caliber have a bore dimension that takes this into consideration. The Ruger .357/9mm may not be one of these, but I remember my old Single Six convertible had an odd bore to accomodate both .22 and .22 mag. Actually, I don't think it worked real well for either caliber. Just my .02

 

[Jimbo357mag]

Don't they have a lot of import GP's in 9mm. Probably cheaper to buy the whole gun than to have a blank cylinder made-up and fitted. :shock:

...Jimbo

 

[protoolman]

Correct me if I'm wrong but isn't the 9mm case wider than the 357? So couldnt a 357 cylinder technically be bored out to 9mm? The throat would be oversize barely and so would the bore but if you shot 9mm lead bullets and left them unsized from the mold or sized them .357 they should work ok right? Extraction could be handled by having the cylinder modified for moon clips.

 

[BigBlock1]

Correct me if I'm wrong but isn't the 9mm case wider than the 357? So couldnt a 357 cylinder technically be bored out to 9mm? The throat would be oversize barely and so would the bore but if you shot 9mm lead bullets and left them unsized from the mold or sized them .357 they should work ok right? Extraction could be handled by having the cylinder modified for moon clips.

That's what I was thinking, modified stock cylinder. I think they do that for custom blackhawk conversions? I know the barrel diameter is a slight issue, but I was thinking about the Blackhawk convertible...does anybody know whether it does have a special size barrel or just the standard .357? I tried a spent 9mm case in my GP100 and it wouldn't quite fit. Seemed slightly larger than a fired .357 case.

I don't want to reload the 9mm, I'd just do .38/357, but, I just like the idea of having a gun that can shoot all sorts of ammo. I think I want to get the Blackhawk conversion in .45 too.

 

[Jimbo357mag]

I stand corrected about needing a blank cylinder but check-out the problems as noted by Iowegan near the bottom of the page. Basically if you use a 357 cylinder the throats would be way too big.

...And, just my opinion, it is much easier to grab a different gun rather than change GP cylinders.

...Jimbo

 

[BigBlock1]

but check-out the problems as noted by Iowegan near the bottom of the page.

Bottom of the page...where?

Basically if you use a 357 cylinder the throats would be way too big.

Ruger does make an "official" export 9mm GP don't they? Maybe I could find a cylinder from one of those...(not from Ruger, of course :roll: )

...And, just my opinion, it is much easier to grab a different gun rather than change GP cylinders.

Well, like I said I'm not really a fan of the 9mm. I could buy a cheap plastic one that holds 17 rounds, but, then where will I put the .38s and .357s? :lol: It's just nice to have one gun that will shoot whatever you can shove in it. I've always loved the idea of the conversion Blackhawks but would rather have something in double action...

 

[greener]

I have a Blackhawk .357/9mm convertible. The accuracy with the 9mm cylinder has been disappointing. I went so far as to load a .358" bullet in a 9mm case to improve the accuracy. It did. I also found a couple of 9mm bullets and loads that would do ok. In the end, it really didn't seem worth the effort to find a 9mm bullet/load that would work when almost anything in .358" would load and shoot just fine as .38 special or .357 mag. I suspect you would have the same problems with the GP100 and change-over would be more difficult than the Blackhawk.

I agree with Jimbo, you would be better finding a revolver chambered for 9mm rather than a .357 convertible.