Is It Safe....

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Speedo66

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OK, that sounds like a line out of the movie "Marathon Man" which put the fear of dentists in me for years. lol

Just picked up a stainless 4" K frame .38Spl. Wondering if a cylinder from a stainless K frame .357 would fit in it, and if so, would it be safe to fire .357's in that frame?

I know I can just buy a .357, just curious about this though, and to find out if anyone has done it. If it's not feasible, a simple no would be appreciated, safety lecture not required.
 
Model number of the .38 would help.

IIRC, the frame window was too small in some years to fit a .357 cylinder. You also might run into barrel extension, i.e. "cylinder gap" clearance issues. If you swap the extractor, there shouldnt be any timing problems with the swap.

Later S&W used universal caliber frame windows so the barrel extension would be longer or shorter as needed to adjust gap for different length cylinders.

As you may know, however, older K-frames with the flat cut at the bottom of the barrel can have forcing cone cracking issues if subjected to a steady diet of hot, light Magnums.
 
I wouldn't think the frame would just completely let go catastrophically.

IF you do this, I'd keep the loads mild (158gr under 1200fps) and very very closely monitor the frame for stretching and stress fractures.
 
It's a Model 64-5, shipped approx. 1989. Barrel is flat on the bottom, but I would only be shooting 158g.

Thanks for the info.
Ive got a 64-2 and my buddy has a 65-2. Ill see if I can measure the cylinder and barrel extension lengths for you, see if its doable.

Pretty sure the frame itself is identical, Ill check the topstraps too. Indeed, the cylinder may be the same and all you may need to do is through-bore the .38 Cylinder.

I take it that this is pretty common practice with Rugers, but Ive never heard of anyone doing it with a Smith.
 
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Wondering if a cylinder from a stainless K frame .357 would fit in it, and if so, would it be safe to fire .357's in that frame?
.

I did this with a mod 64 and it requires changing the barrel as well or cutting it back... the 38 cylinder is shorter than the 357 so the 38 barrel protrudes further into the frame window the make up the difference. (With my gun... other years might differ). I’ve seen others accomplish the same by reaming the 38 chamber deeper to 357... but you end up with less supported forcing come with the 38 barrel f/c further from the frame
 
I did this with a mod 64 and it requires changing the barrel as well or cutting it back... the 38 cylinder is shorter than the 357 so the 38 barrel protrudes further into the frame window the make up the difference. (With my gun... other years might differ). I’ve seen others accomplish the same by reaming the 38 chamber deeper to 357... but you end up with less supported forcing come with the 38 barrel f/c further from the frame
Yep, thats pretty much what I figured.
 
"I’ve seen others accomplish the same by reaming the 38 chamber deeper to 357... but you end up with less supported forcing come with the 38 barrel f/c further from the frame"
The .38Spl. cylinder is safe with standard .357 pressure?
 
It would be much more intelligent to simply buy a .357 if that's what you want. Besides, there is absolutely nothing wrong with a .38 Spl.
 
"I’ve seen others accomplish the same by reaming the 38 chamber deeper to 357... but you end up with less supported forcing come with the 38 barrel f/c further from the frame"
The .38Spl. cylinder is safe with standard .357 pressure?

Safe enough.

Back in the 1970’s it was a fairly common to lengthen the chambers to accept the Magnum cartridge. Cops didn’t make a lot of money back then and it was a cheap and easy modification. As most cops didn’t shoot a lot of Magnum rounds it worked out fine in most cases.

The thing to watch out for is if the cartridge is too long for the chamber.

The L-Frame came along because K-Frame revolvers did not hold up to a lot of Magnum rounds being fired though them. I would expect a modified 38 to have a even shorter lifespan than a Model 66.

Personally I see no reason to do it now days.
 
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The .38Spl. cylinder is safe with standard .357 pressure?

That is something I would NOT feel comfortable recommending on an open forum as “safe” for someone to do to their gun....
I will say though having seen and shot a couple of these conversions that I didn’t feel unsafe pulling the trigger. I believe their weak point is the forcing cone, not the chamber walls in the cylinder.
Your gun, your responsibility.
 
"
The .38Spl. cylinder is safe with standard .357 pressure?

Well, that's the question. I have seen it answered both ways.
1. The Magnum cylinders are especially alloyed and heat treated to withstand the higher pressure.
2. It's all the same stuff, simplifies inventory.

Even if the cylinder stands it, you can shake the gun loose with even "moderate" magnums.

Me? I would not overload Specials and I would not go to the expense of replacing the cylinder.
 
I would buy Underwood's or Buffalo Bore's version of the FBI load for home or self defense, and use standard pressure .38 target loads for range time.
BB https://www.buffalobore.com/index.php?l=product_detail&p=108

Underwood https://www.underwoodammo.com/colle...hollow-point-gas-check?variant=18785707524153

While you're at their websites, check out their other .38 Special loads.
Considering the above two loads do a documented 1,000+ fps from a 2" snub and 1,100+ fps from a 4" barrel, I can't think of anything to not like about them for defensive use.

Since .38 brass isn't expensive, I'd just buy a bunch of it for loading.
Or, buy a bunch of cheap brass cased .38 ammo to shoot and reload the brass.

I have a .38 Special Ruger Speed Six Snub that I've thought about reaming to .357 Mag.
I haven't done it, because the BB and Underwood .38 Spl +P ammo give plenty of performance and I don't see getting a huge benefit from running .357 Mag from such a short barrel, unless I go with Underwood or BB.

Now, my S&W 31-1 probably WILL get reamedfrom .32 S&W Long to .32 H&R. Plenty of safety and wear margin there. Plus, much better SD loads available.
 
So I finally broke down and bought a Model 65-4 in .357 today. Read a few posts on other sites where it was said the Magnums have a slightly different K frame, certain aspects of it were slightly thicker, and the cylinders were different.

Although I don't always treat them well, I do value my fingers and hands so didn't want to watch them fly off if a gun gave way.

It's an ex-police version 65 at a decent price. It's seen a little rough handling on the exterior as a police gun would, but the action itself is still very tight. Came with a nice set of Pachmayr Presentation grips in addition to the stock wood ones, and the springs had been replaced with lighter ones by Wolff.

Also came with a like new Don Hume holster, unfortunatel for a righty, not a lefty like me. It's for sale here on this site.

Looking forward to taking it to the range. This is all because I'm too lazy to adjust dies and powder measures to .38Spl. instead of .357, plus I have much more in the way of .357 cases.

Now I just have to sell the Model 64.
 
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I have a 10-6. I upload .38spl cases a bit. There is a “no mans land” between .38 and .357 when looking at powder charges. I never load to .357 powder charges due to the pressures created by the .38’s smaller case.
 
@Barry loyd My 10-6 sees full power 38s as well. Not even close to .357 pressures, but well into the +p range. Often times it gets loaded with 9mm bullets because I have a pile of those and my barrel is a bit snug so it works out well. Heavy 9mm bullets are like a cross between a standard 38 and a magnum bullet. I really like that combo. I have no clue what the 9mm bullets are but they are flat nosed FMJ weighing in at 138gr.
 
So I finally broke down and bought a Model 65-4 in .357 today. Read a few posts on other sites where it was said the Magnums have a slightly different K frame, certain aspects of it were slightly thicker, and the cylinders were different.

Although I don't always treat them well, I do value my fingers and hands so didn't want to watch them fly off if a gun gave way.

It's an ex-police version 65 at a decent price. It's seen a little rough handling on the exterior as a police gun would, but the action itself is still very tight. Came with a nice set of Pachmayr Presentation grips in addition to the stock wood ones, and the springs had been replaced with lighter ones by Wolff.

Also came with a like new Don Hume holster, unfortunatel for a righty, not a lefty like me. It's for sale here on this site.

Looking forward to taking it to the range. This is all because I'm too lazy to adjust dies and powder measures to .38Spl. instead of .357, plus I have much more in the way of .357 cases.

Now I just have to sell the Model 64.
I had the same model and dash for a couple years. I think it was a 1982 build, IIRC. Fixed sights, trigger was good, but had forcing cone erosion. All in all, it was a good solid shooter. Kind of wish I still had it.
 
Ironically I had a long conversation with my gunsmith last week about the above question. My "smith" is one of the most respected in his field in the country, so I wasn't talking to a wet behind the ears recent grad of gunsmith school. Back in the 70's I remember him boring out the cylinders in many Model 10's for LE Officers Basically converting it to a Model 13.. Most had to buy their own weapons and were held back by local rules of .38 Spl only. Most carried .357 Magnum on duty but had the .38s for inspection or if any questions came up. The original Model 10 cylinder was 1.56" in length and the Mod 13 was 1.67" before the recessing was discontinued and 1.62" after. He said there was absolutely no danger in what he did and has witnessed Model 10's shooting thousand of full .357 loads with no problems. I was also told he had it on good authority that in the late 60's and on that all K frame cylinders were heat treated the same at the factory. There was a lot of rumors during that time that it was only safe to do so it the gun had the heavy or bull barrel, but that was a myth as the barrel doesn't have to withstand any pressure. The heavy barrel was brought about to help with balance and recoil. I won't mention his name just because I don't want to create any more controversy that I may already have as well as any liability. I will say that he would never send a gun out that there was any question in his mind about the safety. I personally would trust anything he built and would not hesitate to shoot it. AS far as the OP's original question, there would probably be a lot more work in changing a cylinder than just dropping in. The forcing cone may have to be modified etc. Unless you are using a .357 for hunting where you want the utmost in penetration and/or expansion at some distance, the newer +P .38 special do a darn good job of giving us what a lot of us loaders tried to create back in the day. You can get a .38 +P today that will penetrate adequately and expand to twice the original size out of a 2" revolver without all the flash, band and recoil that we used to have to deal with shooting .357s for personal defense rounds.
 
If you want to shoot 357 buy a 357. Asking for trouble.
Personally I would never buy a 38 when 357 can shoot 38.
38s are foolishly limited use purchase.
 
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