How hot can it handle? 10-6

[WestKentucky]

I reload. I enjoy tinkering. I know what SHOULD be done (thanks to all of the enablers here) but I just want to know…

The Smith & Wesson K frame for a short time housed a 357 magnum factory cylinder. Essentially a model 10 deep chambered to accept 357 cartridges. That proved to be too much for the gun to handle, but the engineers clearly thought it would work out or they would not have ever given the project the green-light. So clearly, the K frame can take more than 38spl… but how much more? How hot can a 38 go without quickly shooting the gun loose or out of time?

I also know it’s a pretty simple process to convert a 38 cylinder to 357. I don’t really want to do that, but I have considered it and would just make a point to not go nuclear. But still, how hot is too hot? Seems the larger case capacity of 357 opens up some options, but it opens up some risk as well, both in conversion and in use after conversion. For doing the same thing, same bullet at same velocity, the greater capacity of the 357 should mean lower chamber pressure… slightly.

This is just an excercise of the mind at this point. I don’t want to buy another gun just yet. I know what I want and I am willing to save and spend for it. BUT I wouldn’t mind having a 357 lite either. Do I need the power, no not really, and if I do I have a 10mm 1911 to get done whatever needs done.

I don’t recommend people going over book max loads, or doing anything unsafe. Pure academics here…

 

[DR505]

Uh...S&W made numerous .357 magnum revolvers using the K Frame. The Model 13, 19, 65, and 66 are just a few examples.

 

[NIGHTLORD40K]

The issue with .357 K-frames was cracked barrel forcing cones, not anything to do with the cylinder itself. Theoretically, the new production guns with the revised front latch have solved the problem, and are still (supposedly) in production.

I wouldn't personally have any safety reservations boring a .38 K-frame to accept Magnums, but .357 models aren't exactly hard to find, and probably cheaper to buy one than have the .38 machined.

 

[fxvr5]

In case there is any question, Model 19s and 66s are still in production. They are still on S&W's website.

 

[NIGHTLORD40K]

In case there is any question, Model 19s and 66s are still in production. They are still on S&W's website.

Ya, but has anyone seen a new one in the last 2 years......

 

[fxvr5]

Ya, but has anyone seen a new one in the last 2 years......

In stock;

https://www.sportsmansoutdoorsuperstore.com/products2.cfm/ID/207414
https://www.sportsmansoutdoorsuperstore.com/products2.cfm/ID/207415
https://www.sportsmansoutdoorsuperstore.com/products2.cfm/ID/189721
https://www.sportsmansoutdoorsuperstore.com/products2.cfm/ID/134634

And that's just one store.

want more?

Model 19s: https://gun.deals/search/apachesolr_search/022188874969

Model 66s: https://gun.deals/search/apachesolr_search/022188626629

 

[NIGHTLORD40K]

Cool.

 

[243winxb]

a pretty simple process to convert a 38 cylinder to 357

If your 10-6 barrel is marked 38 spec. +P you can shoot that ammo.

Boring the 38 cylinder to 357 may not be safe at 357 pressures. The steel used & heat treating may be different between 38 & 357? S&W may be the only one that knows.

38+P 20,000 PSI
357 mag 35,000 PSI

15,000 PSI difference.

 

[Jim Watson]

Some of Elmer's loads run about 26000 WTHE which is about proof pressure for a .38 Special.

Phil Sharpe showed .38 Special loads of the same pressure as .357 Magnum but no doubt meant only for heavy framed revolvers like S&W Heavy Duty and Colt New Service.

 

[trackskippy]

If youre looking for a 357 "lite", just get a 357 and load it lite. Perfect reason to get another gun.

A lot of people who carried 357's for a living simply loaded them with +P 38's, which Im sure your Model 10 will handle too.

I have both Model 10's and Model 19's, and load them appropriately. I shoot 38's out of the 38's, and 357's out of the 357's.

The hotter 357's are much more pleasant and easier to shoot well with out of the L and N frames too.

 

[doubleh]

I have a 19 I bought new in the '70's. It is an unplesant shooter loaded with 357 to me. It hurt the web between my thumb and fingers with the first shot and just got worse. It is a fine firearms and enjoyable with 38 special loads.

 

[Y-T71]

If your 10-6 barrel is marked 38 spec. +P you can shoot that ammo.

Boring the 38 cylinder to 357 may not be safe at 357 pressures. The steel used & heat treating may be different between 38 & 357? S&W may be the only one that knows.

38+P 20,000 PSI
357 mag 35,000 PSI

15,000 PSI difference.

I think this is what most folks don't understand.

While the frames are the same size and they both use "stainless" or "blued" steel, depending on the years of manufacture, they are not the same steel alloys nor the same heat treatments.

It's really not as easy as just boring out the chambers.

 

[fxvr5]

While the frames are the same size and they both use "stainless" or "blued" steel, depending on the years of manufacture, they are not the same steel alloys nor the same heat treatments.

And we know this how?

 

[WestKentucky]

I think this is what most folks don't understand.

While the frames are the same size and they both use "stainless" or "blued" steel, depending on the years of manufacture, they are not the same steel alloys nor the same heat treatments.

It's really not as easy as just boring out the chambers.

The manufacture of the cylinder has been debated ever since the 357 guns came out. There is no official correct answer about composition or heat treat.

 

[WestKentucky]

It was made abundantly clear in the first post that this is the right thing to do. It was also made clear that this is academic. I don’t understand comments like these when it’s been made super clear.

youre looking for a 357 "lite", just get a 357 and load it lite. Perfect reason to get another gun.

 

[WestKentucky]

Some of Elmer's loads run about 26000 WTHE which is about proof pressure for a .38 Special.

Phil Sharpe showed .38 Special loads of the same pressure as .357 Magnum but no doubt meant only for heavy framed revolvers like S&W Heavy Duty and Colt New Service.

that’s a pretty good reference point. Elmer Keith was an old school hot-rodder and had little reservation in blowing a gun up to find its limitations. I wonder what he would have done with modern bullet and powders at hand.

 

[trackskippy]

It was made abundantly clear in the first post that this is the right thing to do. It was also made clear that this is academic. I don’t understand comments like these when it’s been made super clear.

In that case, load up some 38 cases to full power 357 loads and see how it goes. Ill hold your beer.

 

[Y-T71]

And we know this how?

I'll bet my next paycheck that I've read about the difference in metallurgy and/or heat treatment between S&W revolvers chambered in .38spl vs .357mag in the past (I'm currently unemployed so that doesn't mean much )

I know, as part of S&W "endurance package" on their N frames, one of the changes was to the heat treatment of the crane/yoke.

I sent an email inquiry to S&W to see what they say.

I think we could all agree, since they're the manufacturer, they would be the ultimate authority on the subject.

I'll post their reply as soon as I receive it.

 

[Jim Watson]

I don't know how many guns Elmer blew up, but one culprit seems to have been heavy loading with marginal powders like No 80. When 2400 came out, business picked up.
A gunzine had a picture of two of Elmer's guns, SAA .44s that had been overloaded and blown up. The top straps had been straightened and welded, cylinders replaced. They had King's adjustable sights, the front ramp pinned to the stub of the fixed blade and poorly done.

 

[fxvr5]

I know, as part of S&W "endurance package" on their N frames, one of the changes was to the heat treatment of the crane/yoke.

Different frame, and the crane/yoke is not the cylinder or frame.

 

[Y-T71]

Different frame, and the crane/yoke is not the cylinder or frame.

I know.

What's your point?

S&W used a different heat treat in my example.

What makes you think it wasn't done with other models?

There's more to the OP's question than just the frame.

 

[Pudge]

My understanding is that S&W revolvers with the number designation (model 10 vs M&P) can handle +p ammo.

 

[N555]

Unless hunting, shooting at deer, big cats from out to around 100yd any hot 38 that cranks out bullets hotter than 9mm+p should be quite sufficient.
I load my 38spl hot, between the max load of 38spl+p but less than the start of 357mag for same bullet same powder. But I shoot them in an L frame.
A k frame should last a lot longer running hot 38spl than full power 357mag ammo, assuming the manufacturer just sends them with a 357mag cylinder with "357mag" stamped on the gun.
I'm from the time when a lot of police departments ruined a ton of k frames running 357 ammo in them so to me k frame always means 38spl or 38spl+p and running 357mag makes the life of the gun unacceptably short. I aways heard they were cracking after 1,000 to 1,500 shots running full power 357mag ammo. I would hope the new ones were stronger.
If I had a k frame I would just load book level +p and call it good.

 

[Jonesy814]

A buddy of mine got a nice made in 1969, model 15 with box & documents. One document was on ammo. If these velocities are legit it looks like they all can handle hotter ammo than is offered today. This would have been before there was an an official SAMMI specification for Plus P.

 

[Mike C2]

Around 3000 10-6 were made in .357. Including 1200 for the NYSP. Some of these were restamped 13-1. One reason a 13 no dash doesn’t exist because it was really a 10-6. Info from Standard Catalog of S&W 4th edition. This doesn’t really answer the question because we don’t know if S&W did something different to those guns, but appearances suggest .357 in a 10-6 is a non-issue.