10mm K frame

[pacecars]

After playing around with my 16-4 6" .327 Federal I am finding that I like it more and more. I have had a few K frames like a Model 53, 17, 617 and a couple of 16-4s in different barrel lengths. I have a 610 which is a great gun but would love a 10mm in the K frame if it is possible. Is it possible to rebore and rechamber a .357 K to 10mm? Has anyone done it before? After Jack Huntington rechambered this on to .327 Federal, D&T and gave it an action job I put the 4X Leupold on it and it just feels right and looks right. It is fast becoming my favorite. Now if I could just have one in my favorite caliber

Ronnie

 

[Yendor357]

Ronnie, that's a cool idea. I'll bet it would require a 5 shot cylinder, tho.

Have you ever posted a pic of your 327 with the 4X Leupold? I'd love to see it.

 

[OKFC05]

Is it possible to rebore and rechamber a .357 K to 10mm?

Sorry, no. My Model 646 L frame barely accomodates the .40 S&W (10mm short). Like you said, the Model 610 is a great 10mm revolver

 

[tlawler]

Ronnie, that's a cool idea. I'll bet it would require a 5 shot cylinder, tho.

Not necessarily. The Model 646 is a six shot L frame chambered in .40 S&W. I'm not sure if the cylinder window would be wide enough for the 10mm cartridge, but the cylinder diameter would be the same for .40 and 10mm. The pressures are very similar as well…35,000 vs 37,500 psi.

 

[tlawler]

Is it possible to rebore and rechamber a .357 K to 10mm?

Sorry, no. My Model 646 L frame barely accomodates the .40 S&W (10mm short). Like you said, the Model 610 is a great 10mm revolver

Lol…well, that answers my question.

 

[WR Moore]

You've already noted a problem, but there's another. Rather than worry about the cylinder, you might want to consider the barrel shank wall thickness after deducting the groove diameter and the thread depth.

 

[Sevens]

It makes sense to add that the only .40cal L-frame ever made, the 646 as mentioned above makes use of a titanium alloy cylinder, and steel would not have worked considering how much is stuffed in to the small space. Without the titanium cylinder, S&W would never have built the 646 as a 6-shot L-frame.

So if you did manage to figure out 10mm in a K-frame, I would have to agree that you're talking five shot cylinder at most.

Not that this helps much -- but I will also say that I love 10mm and I love S&W revolvers and I am not recoil averse (love the .460 Magnum!) but I don't even like .357 Magnum in a K-frame.

I can shoot it, but I do not enjoy it. 10mm in a K-frame would be a gun that I would not enjoy shooting. As a smallish hiking backup, I see the utility. But as a gun for enjoying, count me OUT.

 

[pacecars]

I got to thinking about the 5 shot 69 .44 Mag and don't see why a 10mm 5 shot cylinder wouldn't work. Obviously it gets way more expensive in having to have a custom cylinder made and then someone to make Moonclips. It would be an expensive endeavor. I guess it will be a no go. I have spoke to a very good gunsmith about a 10mm Python and if he can get the clips worked out we may have a go at it

 

[pacecars]

Ronnie, that's a cool idea. I'll bet it would require a 5 shot cylinder, tho.

Have you ever posted a pic of your 327 with the 4X Leupold? I'd love to see it.

Here you go. I love the way it handles even with the scope on and to me it just looks "right"

 

[Sevens]

I got to thinking about the 5 shot 69 .44 Mag and don't see why a 10mm 5 shot cylinder wouldn't work. Obviously it gets way more expensive in having to have a custom cylinder made and then someone to make Moonclips. It would be an expensive endeavor. I guess it will be a no go. I have spoke to a very good gunsmith about a 10mm Python and if he can get the clips worked out we may have a go at it

With regards to the 5-shot Model 69, that is an L-frame, but I agree that I believe a 5-shot .400" would fit and work in a K-frame.

As for the Python, I think I remember either an idea -- possibly a rumor, was it? Way back we had folks discussing a .41 Magnum Python.

Was that something I imagined?

 

[doubletapp357]

Beautiful Ronnie! If you dream it someone can build it!

 

[pharmer]

I don't know but it seems the "flat" on the bottom of k frame barrels has always been a weak point. "Thinning" further to .40 would seem to aggravate that. I know new 66's don't have the extension but I have no experience with them. Joe

 

[Yendor357]

That's a beautiful revolver and scope.

If you want to squeeze all the accuracy you can out of a revolver, my money is on the guy rockin the scope.

 

[pacecars]

With regards to the 5-shot Model 69, that is an L-frame, but I agree that I believe a 5-shot .400" would fit and work in a K-frame.

As for the Python, I think I remember either an idea -- possibly a rumor, was it? Way back we had folks discussing a .41 Magnum Python.

Was that something I imagined?

There is a factory Colt Python .41 Magnum floating around. It has come up on Gunbroker a few times but I do t think it has sold or been verified as from Colt. I want to say the starting bid has been $15,000 or so

 

[Gunhohulk]

Do you know what kind of velocities you're getting out of the 6" .327?

 

[colt_saa]

With regards to the 5-shot Model 69, that is an L-frame, but I agree that I believe a 5-shot .400" would fit and work in a K-frame.

As for the Python, I think I remember either an idea -- possibly a rumor, was it? Way back we had folks discussing a .41 Magnum Python.

Was that something I imagined?

In 1964 Colt manufactured 5, 41 Magnum prototype Pythons in blue steel. They had even ran magazine ads offering the Python in several different chamberings. These included the well known 38 Special and 357 Magnum and the not so commonly known 22LR, 256 Magnum, 41 Magnum and another that does not come to mind at the moment

It was originally claimed that the 5 prototypes were destroyed when Colt decided not to offer the Python in 41 Magnum, but at least one escaped destruction because I handled it many years ago

There was a Arlington Texas gunsmith affectionately known as "Bubba" that began building 41 Magnum Pythons in the mid 1970s. There was an article by Jack Fowler on the SixGuns website a few decades ago listing the events.

Colt served him a Cease and Desist letter after one of the 41s was returned to the Colt Factory for service.

By that time "Bubba" had built more than 100 of the 41 Magnums. I have a 6" sitting in my safe. It is at the bottom of this very out of date 41 Magnum group photo

A 5 shot L-framed 41 Magnum would be easy. Taurus built them in stainless and Total Titanium in several barrel lengths over 20 years ago, the model 415. I own the 2 1/2" versions constructed in both materials

So obviously a 5 shot L-frame chambered in 10MM Auto or even 10MM Magnum would be easy once you had designed the moon clips

 

[Sevens]

There is a factory Colt Python .42 Magnum floating around. It has come up on Gunbroker a few times but I do t think it has sold or been verified as from Colt. I want to say the starting bid has been $15,000 or so

Egads to finding any of that .42 Magnum ammo, it's scarce. Never caught on really, I remember their marketing, they really wanted to "one-up" similar and more established cartridges!

 

[steelslaver]

The K frame 357s are know for cracking the barrel at the forcing cone. Part of it is how thin the barrel is because of the flat spot need at bottom of shank to clear gas ring. Taking another .025 away in that area would really make the problem worse, Plus no way 6 would fit and I doubt 5, the la frame cylind is over .11 larger in diameter than a K frame. If you look at a K frame ratchet with 357 or 38 cases you you will see that there would not be room for the clips needed to hold 40s. Plus, measure the outer wall of an K frame 357 and then take away enough for a 40 and you haven't got much left. Even if you went with just 5 your screwed because you can't move them inward because of ratchet and thin spot on bottom of barrel

Pipe dream, the K frame is maxed out at 357

The L on the other hand could do it

 

[robertrwalsh]

I am confident it would work just fine as long as you never actually fired any ammo in it. That would kind of reduce the utility though.

 

[stansdds]

I agree with Steelslaver, the K-frame's cylinder and barrel simply cannot safely handle anything beyond a .358" diameter bullet cartridge.

 

[mchom]

It's the wrong brand

But pretty close to OP's idea

 

[pacecars]

But pretty close to OP's idea

I had David Clements build a 10mm GP-100 long before Ruger wised up and built one

 

[steelslaver]

One of Ruger's advantages is their stop notch is off center to chamber even with an even number of chambers. Also a beefier frame allows for larger barrel shanks. Rat is why their 45 colt cylinders will take more pressure in either the RedHawk or BlackHawk as they are the actually extremely close to the same OD as those of a S&W N frame

 

[pacecars]

Egads to finding any of that .42 Magnum ammo, it's scarce. Never caught on really, I remember their marketing, they really wanted to "one-up" similar and more established cartridges!

Thanks! Oops! But the .42 Magnum would be the more appropriate name for the .429 bullets of the ".44 Magnum"

 

[pacecars]

The barrel shank would be the issue then. Thanks for the responses. I would think using "Carpenter steel" for a new cylinder would take care of that part but you can't get around the frame issue. I would love to see the L frame in the 10mm in addition to the 610 N frame. The 610 should come in 10mm Magnum from the factory. My favorite 610 converted to the 10mm Mag

 

[WR Moore]

About "Carpenter steel". Steel specs are generalized by the ASME for the different types. 1000 series is plain carbon steel, 4000 series is chrome moly steel. The last two digits are generally carbon content. The specs for the various types include ranges of various other trace contents, like sulfur for easier machining, vandium and other materials. Often shows in the 3rd digit.

When you get to the proprietary steels, like Carpenter 158, you're looking at one of the ASME classes with proprietary amounts of the various alloying materials. Possibly with tighter allowable variance of the amounts of those materials. These things often result from someone's theory that the particular blend will have superior characteristics for some special use. That theory may/may not have lab test results that confirm that.

Without knowing what special qualities may exist (improved tensile strength, shear strength, elasticity, etc), if the differences are significant, and if/if not they have any bearing on your application, debating steel types is pretty meaningless.

Sometimes what's used in development/prototype work is what's on hand. Depending, that may carry over to production. There really aren't any magic materials, there's often a lot of interchangability.

 

[steelslaver]

Carpenter made a lot of different steels. Some of their CPM steels are great, but they are not magic. Do what I have done. Take a set of calibers, start measuring and doing the math. My holy grail is a 5 shot 45 acp with a alloy L frame. I have bought a 696 a model 69 a 396 and a 296. I have measured and remeasured. Can't happen unless S&W redsigns the lock work to use a smaller ratchet the size of Charter Arms, and moves the chambers inward and the center of the barrel down even with the beefier barrel shank uses with the 2 piece barrel on the model 69.

The bottom of the barrel on a K frame 38 or 357 is just .047 thick. .400-.357=.043 .043/2=.0215 .047-.0215=.0255 That is not much metal when you want to guide bullets with it. It already cracks from time to time with some loads. Then the outside wall of a K frame 357/38 is just .066 thick. A 357 is .379 at the base and a 40 is .424 so .424-.379=.045 and 1/2 of that is .0225. .066-.0225=.0435 to contain the pressure. Nobody nowhere is going to take the liability for that taking the same pressures as a 357. They would be nuts to do so.

 

[keithhagan]

K-frame maybe, L-frame definitely

L-frame, for sure. I've done it twice.

1. once by taking a steel 357 cylinder and rechambering to 10mm then fitting to my 646
2. another by taking a 6" 686-5 and having both the barrel bored and re-rifled to 10mm and the cylinder rechambered to 10mm magnum. I rechambered a second cylinder to a rimmed 10mm magnum using 30-30 brass.

K-frame, possible under certain circumstances:

• Custom 5-shot cylinder
• can't use the model 66/19 with the flat barrel shank (the vast majority), must use the new style from the 66-8 (thicker) even then not sure if thick enough. Will also need to contend with two-piece barrel

That said, S&W could do a 5-shot 10mm on the K-frame if they would do what they did to the L-Frame to get 44 magnum to work (compare Model 696 to 69). There, for the 44 magnum chambered 69, they used a one-off larger diameter barrel shank than is standard on the other L-frames.

I'll note, if you just want a small revolver in 10mm and don't need it to be double-action, you can have a Ruger Single Seven (or Single Six/Ten converted to centerfire) fit with a 5-shot 10mm cylinder and barrel. They're even smaller than a K-frame.

 

[steelslaver]

If they put a bigger barrel shank in a K frame they would need to increase the size of the frame where it threads in, because the portion under the barrel is already real thin. IF you make it thicker there you would have less material left on top of the yoke and guess what? There isn't much there now. Its .035 from ejector rod to the top of yoke. If you move the rod down it moves the cylinder down so you have to make the chambers farther out to line up with the bore and there is absolutely no material there to do that and still have steel left for outside of the chamber
There is .460 between the center line of a K frame cylinder and the chambers and hence the center of the barrel. Once you add up 1/2 the ejector rod, a bit from the ejector rod to the top of the yoke, then a bit for some frame frame under the barrel plus 1/2 the barrel shank there just isn't anything left for a larger barrel and shank unless you make the cylinder larger and then as you also have to make the frame larger to hold that cylinder, you have a L frame. LOL.

I have a set of calipers in my desk drawer along with J, K, l and N frames. I have maybe 20-30 loose cylinders from J frame to X frame and as many barrels in my shop. I even have a loose model 69 barrel. I know what the numbers are. You add to one you must subtract from others and visa versa.

A K frame is tapped out at .357 unless you want to keep the pressure down to the point your way more than defeating the point of trying to have more effective round.

I don't get why all those who want a 5 shot big bore don't do like I did and get a 396 or 386 (I have both) Lighter than a steel K frame, same grip size and the cylinder is just 0.10 bigger around. That is the thickness of 2 dimes. If that gives away your conceal carry or makes you uncomfortable, I suggest you carry a J frame anyway

 

[stansdds]

The K-frame, like Steelslaver has said, is simply a no-go with a caliber larger than .38/.357. There simply is not enough steel in the barrel shank and frame, even if the cylinder was stronger. The L-frame and Ruger GP-100 (pretty much the same size as the L-frame) are a different story. Larger diameter barrel shank, more steel surrounding the barrel shank, and a larger cylinder.