T&K Customs 9mm conversion cylinder

[Atari1977]

Hey y'all, I'm looking at picking up a 9mm revolver. I'm aware of the downsides but I like to keep my ammo consolidated down to pretty much just 22lr, 9mm, and 5.56.

Anyway looking around the options in the market are pretty slim and I'm pretty much honing in on picking up a S&W 547. However I also saw that T&K Customs can convert .357 cylinders to accept 9mm, which would get me basically what I want, a stainless K frame in 9mm.

Does anyone have experience with a converted cylinder? How's the accuracy of 9mm in a .357 barrel?

 

[DukeSoprano]

Your bullets may tumble, I use a .358 bullet for 38 Super.

 

[steelslaver]

Also no +P and the only 6 shot K frame 9mm moon clips that I know of out from TK custom and about $8-9 a copy

I bought some clips and modified 2 K frame 38 cylinder similar to how TK does them and thy work OK. I have not noticed any bullet tumbling or Key holing. While 9 mm bullets are only .355-.356, but in a 38 or 357 the land DI is under .350 even though the groove dia is .357. They will spin.

 

[Kenneth07ex]

Also no +P

With a .357 conversion?

 

[max]

I have worked with Tom for over 30 years. All of his stuff is first rate. I don't think you would be disappointed.

 

[racer19j]

When .38/.357 cylinders are converted to 9mm, there is a distance between the cylinder and the throat that doesn’t get machined. To get a true 9mm chamber you need to start with a smaller chamber like a 22lr, such as a 617 cylinder. This will give a true 9mm chamber with a full length throat.

 

[steelslaver]

With a .357 conversion?

From their site Cylinder Machining for S&W Firearms Revolvers | TK Custom Store


Note:

Our work on cylinders rechambered to 9mm are LIMITED to our customer's using standard 9mm ammo or low pressure reloads, which are 34,000 - 35,000 psi chamber pressure or less. Same chamber pressures apply to firing of .38 SPL & .357 Mag. Examples of FACTORY Brands are: Winchester, Federal & Remington.

Absolutely NO 9mm Nato, 9mm +P or 9mm +P+, all which are far beyond the 34,000 - 35,000 psi chamber pressure our Ruger .45 ACP & 9mm cylinder machining is intended for. Usually 38,500 psi, which WILL Stick!

If you try to use these high pressure ammo, you will experience cases sticking in all chambers.

We cannot warranty our work, if you disregard our warning/notice on high pressure ammo.

When rechambered to 9mm the cylinder will still shoot NON-HIGH Pressure ammo, 38 SPL or 357 Mag with or without the proper Moon Clip.

Reloaded range brass, with the unsupported barrel chamber bulge, will not resize properly and results in inferior ammo for use in this conversion!

 

[steelslaver]

I would suspect that even if you were to ream a K 22 cylinder to fit 9mm cases perfectly, with .356 throats, you would still experience sticking with high pressure 9mm+P. Just to much pressure for that sized cylinder.

I reamed a K22 cylinder to 22TCM, which has a slightly smaller case diameter as it is based off the 223 case. The 22TCM has a .372 base vs the 9mm .391 The brass itself should also be thicker at the base as the parent brass is for 55,000psi rifle pressure
Max pressure loads of the 22TCM run at the same pressures as 9mm+P
and stick in my cylinder

Before some one says something about cylinder heat treat of the K22 vs the 357. The heat treatment of steel CAN NOT change its elastic modulus, the amount that it moves and returns under a given pressure. That ability is fixed across all steels. The thing that heat treatment CAN change is the elastic limit, which is the point at which it fails by permanently being deformed in some manner. They are not failing, the stop notches are not bulging etc.

 

[JimCunn]

"Does anyone have experience with a converted cylinder? How's the accuracy of 9mm in a .357 barrel?"

No change in accuracy. The SAAMI specs for barrel land and groove diameter are the same for both calibers.

 

[tflt]

L Frame maybe

This was done by Mark Hartshorne at Pinnacle and gets a steady diet of Speer Gold Dot, no sticking, slightly less accurate on paper compared to handloaded 357,158 grain LSWC's at 900 FPS, but rings my steel plates all the same.

 

[jculloden]

My spare cylinder for 60-4 was converted by TK Custom to 9mm, Excellent work and no problems

 

[ysr_racer]

S&W factory 9mm barrels slug at .357 so no loss in accuracy. TK does excellent work.

Factory 9mm ammo gets light hits and tons of bullet creep in my factory 9mm S&W 929.

 

[PhilT]

From my experiences, TK Custom does excellent work. If something isn't right, they will fix it.

 

[jculloden]

/it's a shame Mark isn't taking any new work, he did a great job on my 442 for moon clips

This was done by Mark Hartshorne at Pinnacle and gets a steady diet of Speer Gold Dot, no sticking, slightly less accurate on paper compared to handloaded 357,158 grain LSWC's at 900 FPS, but rings my steel plates all the same.

 

[Atari1977]

Well thanks for the info y'all.

I decided to just go with a S&W 547 for this, think it was the closest to what I'm really looking for.

Though if I find a good deal on a 66 or 64 nearby I'll probably go ahead and get a second cylinder to convert for em.

Shame that S&W doesn't just make a new 9mm revolver with the 547 extraction system.

 

[Engine49guy]

SW was recently offering an L frame 9mm as well as an N frame 9mm iirc.

Ruger sold single action Blackhawk revolvers in .38/357 some came with a spare 9mm cylinder,
They are still out there and since it's a cowboy style revolver you don't need moon clips.

Iirc Taurus may have offered a 9mm revolver,

Can't recall the name but there was a German company that offered an L frame 9mm cylinder a few years ago but IIRC they cost as much as the gun.

 

[Atari1977]

SW was recently offering an L frame 9mm as well as an N frame 9mm iirc.

Ruger sold single action Blackhawk revolvers in .38/357 some came with a spare 9mm cylinder,
They are still out there and since it's a cowboy style revolver you don't need moon clips.

Iirc Taurus may have offered a 9mm revolver,

Can't recall the name but there was a German company that offered an L frame 9mm cylinder a few years ago but IIRC they cost as much as the gun.

I did look at the current S&W 9mm offereings but I don't think they really do it for me. I think it's mainly an aesthetic thing, I don't really like the look of the 986 or 929. Might be better if they had a version without the titanium cylinder so the finish would be uniform.

Blackhawk is a good option but I was looking specifically for a double action.

I did see the Korth conversion cylinders but didn't find a whole lot of info after their announcement in 2016 or so. So I presume if those are out there that they're extremely rare since they were selling for about $900 new.

Charter Arms does make a 9mm double action revolver that doesn't need moon clips but besides not wanting to get a cheap revolver I think they only sell it with a 2" barrel and I was looking for a 4".

 

[Lou_the_welder]

I have a 929 and a 547. I definitely shoot my 929 more than the 547. Moonclips make that possible.
The 547 is a good gun. As long as the extractors tabs are in good working order. I had a chance to inspect two 547's at the same time, and I chose the one that held the snapcaps better, so I would check that if I could.

I wouldn't cut a k frame for 9mm- but that's just me. I already shoot 9mm out of every 357 I have. They're called 38 short colts! Using 9mm bullets. I've even shot 9 mil out of special cases. Same enchilada.

 

[Drm50]

I just got a 37-2 Airweight with extra 9mm cylinder, machined for moons.
Cylinder work by Pinnacle? Haven’t shot it at all yet, just got it few days ago.

 

[SuperMan]

Have had the S&W 940 and two LCRs in 9mm and both locked up when using +P ammo. Also have a 547 but have never run +P in it.

Had TK do cylinders for a 3" 66-2, 60-10 and a 649-2 that will run .38 Super and 9mm via moon clips. Have never shot 9s from any of them but the Supers shoot great and being a straight wall design have had no backing out problems...

Bob