Educate me on Ruger 357/9mm convertibles

[Bubba w/a 45/70]

The title pretty much sums it up.

What are the minuses to having these versus a single caliber revolver from the Ruger single action family?

The large plus would be the ability to use 9mm's in one of my revolvers, but is this worth it? I have plenty of 9mm ammo and the magazine fed shooters to use it.....along with plenty of 357 ammo and revolvers to use THAT also!

Just something that seems to keep itching, but usefulness outweighs "fun" for me at thee end of the day.

[Solothurn]

My Ruger Flattop is accurate with 9mm FMJ. I haven't shot lead 9mm through it yet.

My .357 cylinder has .358" throats and shoots great with lead. The 9mm is @ .355". Has anybody opened a 9mm cylinder up to .358", and was it still accurate wth jacketed bullets?

[Outpost75]

My Ruger .357/.9mm convertible was an older one with .358" cylinder throats in both cylinders. I have since had it rebarreled and both cylinders rechambered by John Taylor to a .40 S&W and 10mm convertible, which I like very much.

Firing typical 9mm jacketed ammunition in the 4-5/8" Blackhawk Convertible with 115-124-grain bullets were 4" low at 25 yards compared to 158-grain .38 Specials or .357s. Groups were also 3-4," about double what I would expect with my .38 or .357 handloads.

The stop surface of the 9mm chamber used to headspace the case mouth had a sharp corner and caused little rings of lead to be shaved from cast lead bullets which were a correct fit in the chambers. I fixed this by using a 3/8" ball chamfer tool from Brownells to break the sharp corner, then the revolver shot about 2" at 25 yards with 147-grain .357 commercial hard cast bullets and 3.2 grains of Bullseye. It also shot better, about 3" and to the sights with 147-grain jacketed 9mm, but lighter bullets required re-zeroing and were less accurate. 3-4" as before.

My S&W Model 940 9mm revolver has .356" cylinder throats and also shoots low with 115-grain and 124-grain factory 9mm, but it shoots Speer Gold Dot G2 147-grain ammunition to the sights and gives 950 fps from its 1-7/8" barrel. Accuracy is very good for a DAO snubby, about 2 inches at 50 feet when sandbagged.

I rechambered the 940 cylinder with a ".38 S&W rook rifle" reamer from Manson so it can now use either factory 9mm ammo with clips, or .38 S&W lead bullet factory ammo or handloads without the clips. Firing .38 S&W 146-grain lead factory ammo in the rechambered S&W Model 940 with its tighter .356" cylinder throats gives about +50 fps higher velocity than my S&W Terrier Model 32-1 with 2" barrel and .360" cylinder throats.

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[MT Gianni]

I bought a 9mm cylinder and handfitted it to my 6 1/2" 357 BH. I don't shoot it a lot but is gives me an option to swap out a cylinder in the field and shoot that I would not otherwise have. Cast pics had an excellent write up by Beagle but it appears to be gone.

[Bazoo]

The real benefit in my opinion would be to the person that doesnt have/want a 9mm automatic. 9mm is a fair amount cheaper than 38s round here. And it would probably be the most easily scavenged in a survival situation.

I dont have, nor do I really want a 9mm. But I do want a blackhawk convertible. Pretty good chance i'd get a few boxes of 9mm off some friends when they trade guns monthly or there abouts.

[Ickisrulz]

I think that particular combination would appeal more to individuals that do not reload. You can get steel cased 9mm pretty cheap. If you reload, the cost between 9mm and 38 Special isn't much.

The 45 ACP/45 Colt convertibles make much more sense to me anyway. I love mine.

[Walks]

My 1974 NM Blackhawk WAS a convertible, until some thief walked off with the 9mm cylinder while I was down range changing targets.
All I remember is the LYMAN #356402 in my 9mm handloads sized .356 did not give anywhere the accuracy that the .38SPL or .357MAG handloads did.
Of course that was 43yrs ago, but in my one experience I do seem to remember the group sizes were twice the of the .357MAG target loads.

[Bubba w/a 45/70]

The general consensus seems to be that a 9mm conversion isn't quite up to par with the 357 in the same gun when looking at accuracy use/expectations. This is about what I thought would be the case due to the different barrel diameters and such required for the calibers.

Perhaps a dedicated 9mm revolver is what I should consider if looking to use 9mm from that type of handgun,as opposed to trying to make something work that won't.

[contender1]

I'm opinionated. I own a "few" of these convertibles. All OM's.

[bobthenailer]

A few months ago Handloader mag #313 (april 2018) did a write up on the 357/9mm swap cyl . finding a load that shot to point of aim for all could be a problem , however the article has it somewhat figured out for you with velocities and loads and the drop on each load . using a fixed sight Ruger Vaquero and using a Caldwell HAMMR mechanical handgun rest with the same aiming point @ 25 yards ,loads were from 14.0 " low to 1.5 " low for the 9,38&357 using the chart you can come up with a load that could be pretty close to the same POI

[Outpost75]

Point of impact is determined in revolvers more by bullet weight than velocity.

If the bullet weights of your .38/.357 loads and your 9mm loads are close, they will shoot closer together.

If you use mostly 150-158-grain loads in your .38/.357s, then use 147s in your 9mm and they will be "close enough"

If you shoot mostly 125-grain bullets in your .38/.357 loads you won't notice a meaningful difference in POI with 9mm.

Accuracy still depends upon cylinder throat fit.

If your 9mm cylinder has throats larger than .356" just load .357 bullets for it!

Re-Read my post #3 regarding breaking the sharp corner of the 9mm chamber stop surface if you plan to shoot lead in it.

[Larry Gibson]

Back in the '70s I had a 4 5/8" barreled Ruger 357/9mm. I did like it and found, just as Outpost75 mentions, that with .357 sized bullets accuracy was on par with 38/357 loads. I found milsurp 9mm was moa of grouse out to 25+ yards and the bullets zipped through with little damage. I let myself get talked out of it in a trade as I was shooting 357s in a 6" S&W at the time, had sold off my 9mm semi's and wasn't shooting it. Now I wish I still had it .......

[bob208]

I heard two stories as to why ruger made the .357-9mm pistols. first was so you could go anywhere in the world and get ammo. the other was in the 70's a lot of the 9mm smg ammo was coming in and it gave a good safe pistol to use it in. I have one it shoots good with no problems. just nothing supper spectacular about it nor anything supper bad.

[higgins]

My flattop convertible has the same size chamber throats in both cylinders, averaging about .359. As you could anticipate, cast .358 and .359 bullets shoot good in the 357 cylinder; the closest I've come to reasonable accuracy with 9mm is a 147 gr. JHP over a max. load of titegroup, but 147 gr. Berrys plated bullets over a max. load shot poorly. Accuracy with 115 gr. FMJ or plated was miserable, whether handload or factory.

POI is close enough between 150 gr. cast SWC in .38 spl. and the 147 gr. JHP in 9mm. Maybe you'll get lucky and get a 9mm with throats closer to groove diameter than I did. Even with the mediocre performance at best with 9mm, I like the idea of having a convertible revolver chambered for two popular cartridges.

I don't have a 9mm pistol, so I could experiment with larger diameter bullets in 9mm but haven't yet done so.

[Thumbcocker]

My 9mm cylinder was worked over by Dougguy. With noe 135 rnfp it shoots about as well as .38's in the .357 cylinder. There is a preference for the heavy boils sized. 358. I use inserted range brass and have never gotten down and dirty with load development. The advantage is free brass, shipping your lead supply, mild recoil, and how cool that little case looks surrounded by all that steel.

[charlie b]

I am another who had a .45 ACP/Colt Blackhawk. I think I shot ACP out of it once. Then put that cylinder away as the .45 Colt was just as easy to reload and more versatile.

I can see how 9mm/.45ACP would be good in a revolver for speedy reloads with clips, but, beyond that I would not see a need for one unless you don't reload. 9mm commercial stuff is pretty cheap.

[contender1]

Many gun designs are due to low cost ammo being available at the time.
Years ago,, 38 Spl was THE LEO caliber in duty guns. Then the 357 came along,, and the 38 was used a lot because it was cheaper to buy and very plentiful.
When the .30 carbines of WWII & Korea came along,, so did a LOT of cheap mil-surp ammo. As such,, Bill Ruger introduced the .30 Carbine Blackhawk.
When the semi-autos started taking over in LEO's,, many old timers had free ammo, so they still wanted a revolver, and as such, Ruger, S&W & a few others built 9mm DA revolvers.
This was also the time that it was decided to introduce the 9mm cylinders in Ruger Blackhawk 357's.
It was a marketing idea,, to sell a gun that could do more,,, and in many places,, allow the folks who had easy & cheap to free access to ammo a gun to use it all.
Same thing with the 45 Ruger convertibles. Mil-surp ammo was plentiful until the military dropping the 45 acp as their official sidearm caliber.
Marketing,, pure & simple. ESPECIALLY to the non-reloading types.

But,, they do have their purposes. And they can & will often shoot quite well when tweaked a bit.

[Bubba w/a 45/70]

Alot of good advice on the ammo and what needs to be done with the 9mm side of the revolver in order to make it do what it should be able to do.

I am not completely sold on it, and keep leaning towards the LCR in 9mm.....in order to have it work best without making up dedicated loads, as my current load works GREAT in my magazine fed pistols.

I just have the old idea in mind that having a tool that pulls double duty is more useful....not always best, just more useful.

[BigAl52]

I just bought one about a month ago. Ive shot it a couple of times and I like it. But I knew going into the purchase of it, it wasnt going to be a gun that would stack bullets on top of each other when shooting it with the 9mm cylinder. I bought it for plinking with 9mm and it shoots good enough at 15 to 20 yards to do clay pigeon MOA on the dirt banks where I like to shoot. Dont hit them every time but often enough for the fun factor.

[tazman]

The general consensus seems to be that a 9mm conversion isn't quite up to par with the 357 in the same gun when looking at accuracy use/expectations. This is about what I thought would be the case due to the different barrel diameters and such required for the calibers.

Perhaps a dedicated 9mm revolver is what I should consider if looking to use 9mm from that type of handgun,as opposed to trying to make something work that won't.

I picked up a S&W 929 8 shot 9mm revolver. It used moon clips and had to have them since the chambers don't have stops in them to hold the cartridges in place. The revolver is extremely accurate and easy to shoot well. That said, I can't shoot it a fast as Jerry Miculek can.