Any Gunsmiths Here?

[SmeeAgain]

I was comparing my old duty weapon a S&W model 19 (.357 mag) to a model 13 (also .357 mag) and a department issue model 10 with a heavy barrel. (.38 spec).
They all share the common "K frame" and all have heavy barrels.
We can say the 13 and 19 are essentially the same except for some overpriced add ons.
The model 10 has a shorter and slightly thinner walled cylinder as it's not subjected to the increased pressure of the magnum cartridge.
With the exception of the model 10 barrel being longer on the cylinder side (to make up for the shorter cylinder) everything else appears identical.
So... my question is this... If the model 10's barrel was shortened to accommodate the longer magnum cylinder and the cylinder swapped out to the .357 magnum version, would this essentially convert the model 10 to a model 13?

 

[X62503]

Certainly. 10-13’s are well known to savvy revolver aficionados, and just about any gunsmith can help you level up.

 

[dfariswheel]

The Model 10 was never made to handle .357 Magnum level pressures.
They may look the same, but S&W didn't heat treat the frames and cylinder the same in past years.

If you converted a Model 10 to Magnum, you'd probably have frame stretching, cracking, and head space problems.

Converting a revolver made for the .38 Special to Magnum is definitely NOT a thing to do.
Yes, I know the Ruger SP-101 and a few other revolvers could be converted, but they had the stronger heat treating.

The key tell here is that likely you won't find a reputable gunsmith who will do something like this.

 

[SmeeAgain]

The Model 10 was never made to handle .357 Magnum level pressures.
They may look the same, but S&W didn't heat treat the frames and cylinder the same in past years.

If you converted a Model 10 to Magnum, you'd probably have frame stretching, cracking, and head space problems.

Converting a revolver made for the .38 Special to Magnum is definitely NOT a thing to do.
Yes, I know the Ruger SP-101 and a few other revolvers could be converted, but they had the stronger heat treating.

The key tell here is that likely you won't find a reputable gunsmith who will do something like this.

I feel like arguing that.
The "K frame" manufactured today and in recent years is a K frame. It doesn't know which model it will eventually become so when a batch of frames are made, I don't see the advantage of intentionally making some weaker than others.
Would I try this with a 100 year old frame, made prior to the .357 magnum cartridge? Absolutely not!
Logic suggests that they will make them as strong as possible with the technology and materials available.
As previously stated, the cylinders are different! It might be interesting to test one to the point of failure under safe / lab conditions but I think we all agree that eventually it will fail.
As for the frame and barrel, being manufactured almost exacly the same time period for all three revolvers, I'll bet the quality is identical.

 

[Jonesy814]

The first model 13’s were model 10’s that S&W built as 357 magnums. I never have heard that the heat treatment was different, but have never heard it was the same either... they don’t say

 

[ontarget]

From a pure logistical standpoint I can't see the factory heat treating frames differently.
That would be a liability nightmare if they ever got mixed up.

 

[JTHunter]

What is the age of this Model 10? Do you have any knowledge of HOW it has been treated and cared for by previous owner(s)? If the 1- is more than 25-30 years old, it is very possible that there have been changes in the metallurgy and/or alloy make-up of the 10 vs. the 19. If the actual metal used the frame of the 10 isn't the same, it might be unwise to tamper with the 10 in that manner.
Be safe - not sorry.

 

[earlthegoat2]

Logically, if it says 38 Spl on the side of the barrel then that is what you should shoot in it.

Logic is pretty easy.

 

[SmeeAgain]

Apparently I'm not the first to consider this... it's actually a very popular conversion. Even the factory has done it!
I'm not going to molest this one. A. There is no need, I have the models 13 & 19 to shoot if I want.
B. The historical significance of it is of sentimental value to me... only me, nobody else would care.
As a department issued weapon it has extensive holster wear but hardly any actual use.
Speaking directly to a gunsmith, he told me that many WW2 era model tens had the cylinders drilled to accept the longer .357 mag cartridge! Apparently with no recorded casualties!
I wouldn't dare try that! I personally measured the cylinder wall difference between the model 10 and model 13. It's significant!
I'm sure the engineers at S&W had a reason for that!
In any case I thank everyone for their input. It's been an interesting topic.

 

[Jonesy814]

According to the Standard Catalog of S&W:
The Model 19 is built on a frame that is slightly larger than a standard K frame in the yoke area.
The catalog doesn't say why, but you can pretty much see that the ejection rod shroud wouldn't match up quite right with the frame. That makes it easy for the factory to not get those mixed up with model 10 frames.
I have seen forum posts about guns with over -stamped model numbers and read accounts of one frame being pulled from production and having a different model number stamped over the original. This seems to have mainly occurred in the 50's and 60's. They are doing a run of N frame 357's for example and get in a special order for a 44 mag with a configuration that they don't have in stock. They grab a frame, have it re- stamped and build it as a model 29 instead of a model 28 because they know its going to be a while before they do a run of m29's.
If this is how they did things, and it seems to be, then I would think they are all heat treated the same. To heat treat 22 caliber to one level, 38 to another and 357 to yet a third standard seems overly complicated with too much risk of error

 

[SmeeAgain]

According to the Standard Catalog of S&W:
The Model 19 is built on a frame that is slightly larger than a standard K frame in the yoke area.
The catalog doesn't say why, but you can pretty much see that the ejection rod shroud wouldn't match up quite right with the frame. That makes it easy for the factory to not get those mixed up with model 10 frames.
I have seen forum posts about guns with over -stamped model numbers and read accounts of one frame being pulled from production and having a different model number stamped over the original. This seems to have mainly occurred in the 50's and 60's. They are doing a run of N frame 357's for example and get in a special order for a 44 mag with a configuration that they don't have in stock. They grab a frame, have it re- stamped and build it as a model 29 instead of a model 28 because they know its going to be a while before they do a run of m29's.
If this is how they did things, and it seems to be, then I would think they are all heat treated the same. To heat treat 22 caliber to one level, 38 to another and 357 to yet a third standard seems overly complicated with too much risk of error

Imagine the disaster if just one slipped through where someone was injured.
The gunsmith I talked to mentioned a huge order from a police dept in the early 70s for model 13s.
S&W did exactly what you said, restamping model 10s to 13-1s & sending them out.
If true, that confirms the heat treatment question.
The model 10 I have was so incredibly inexpensive, I should have bought at least two... one to preserve & the other to experiment with.

 

[WestKentucky]

As for drilling to accept 357… a 3/8 drill bit does that work easily. The issue is cleaning the hole up where a drill bit leaves ugly toolmarks that can grab onto a cartridge making extraction very difficult. That’s not hard to fix but it has to be done.

As for the sensibility in doing it… if you want a 357 buy a 357. If you want a 38 buy a 38. If you just happen to have a 38 and want a 357 then there is absolutely room for discussion but hot 357s in a thin walled cylinder is a recipe for disaster.

I will eventually drill out my model 10 but I don’t use factory ammo and I don’t load 357s nuclear hot anymore either. The hot loads all got used up in my buntline which was built to be a 44 mag so it’s got PLENTY wall and barrel to handle the pressure.

 

[SmeeAgain]

As for drilling to accept 357… a 3/8 drill bit does that work easily. The issue is cleaning the hole up where a drill bit leaves ugly toolmarks that can grab onto a cartridge making extraction very difficult. That’s not hard to fix but it has to be done.

As for the sensibility in doing it… if you want a 357 buy a 357. If you want a 38 buy a 38. If you just happen to have a 38 and want a 357 then there is absolutely room for discussion but hot 357s in a thin walled cylinder is a recipe for disaster.

I will eventually drill out my model 10 but I don’t use factory ammo and I don’t load 357s nuclear hot anymore either. The hot loads all got used up in my buntline which was built to be a 44 mag so it’s got PLENTY wall and barrel to handle the pressure.

One potential problem nobody mentioned yet...
Upgrading the cylinder to handle the higher pressure sounds like it will safely work. However, drilling / reaming won't help with pressure, merely allows inserting a longer cartridge.
While the person doing it might be OK accepting the risk for himself... none of us are going to live forever.
What about the next guy that ends up with it? Will he even notice it's been compromised?
It sure would suck to cause someone else to get hurt.

 

[Paul7]

Heck, the Model 19 barely handles .357s, why try it with an altered Model 10.

 

[SmeeAgain]

Heck, the Model 19 barely handles .357s, why try it with an altered Model 10.

And that is based on...?
Over the decades, I've shot many thousands of rounds through both the model 13 and 19... sometimes with stronger than factory loads.
I've carried all three on duty as well.
I have yet to see or even hear of the slightest issue... until now.
If you believe you have a valid claim, perhaps you should hire legal representation and pursue civil litigation against S&W.
You and your attorney might become extremely wealthy.

 

[ditmo]

Cracked forcing cones with the 125gr bullet or so I've read. My 19-5 has over 40K rounds through it. 60% are 38 spl but still a lot of rounds. It's a little loose but still shoots and is in time.

 

[Paul7]

And that is based on...?
Over the decades, I've shot many thousands of rounds through both the model 13 and 19... sometimes with stronger than factory loads.
I've carried all three on duty as well.
I have yet to see or even hear of the slightest issue... until now.
If you believe you have a valid claim, perhaps you should hire legal representation and pursue civil litigation against S&W.
You and your attorney might become extremely wealthy.

Lucky you, but it is based on my experience. I recently bought a 19-4, my first S&W. After problems encountered during my first trip to the range it went straight to my local gunsmith to be retimed. He speculated it had too many .357s through it. The GB seller reimbursed my repair cost. Why would I sue S&W for the previous owner misusing the gun? Am surprised you've never heard of this well-known issue, do a google search and you'll find tons.

https://castboolits.gunloads.com/archive/index.php/t-386576.html

"The K-frame .357s were never designed to last with a steady diet of full-charge .357 Magnum loads. Back in the day the Model 19 came out the usual practice was for police to use standard pressure .38 Special for practice and qualification, but the Model 19 could stand moderate duty use of .357 ammunition. The gun was not intended to exceed a ratio of 6:1 of .38 Special to magnums, and that being only when the gun would be touched by a factory-trained armorer on an annual basis to make adjustments necessary to keep the gun in proper time and adjustment.

By the 1980s police training and doctrine had evolved to require officers to qualify with the same ammo they carried on the street. This resulted in greater wear and tear and shorter service life of the guns. The Model 19 was no exception and recommended practice was not to exceed a 50-50 ratio of standard pressure .38 Special to +P service loads. Standard pressure ammunition was still used for practice, but duty ammo used for actual qualification. Use of .357 ammunition was still recommended not to exceed the 6:1 ratio of .38 Special (combined of all types) to .357s.

It is normal for a K-frame .357 to develop end-shake after about 1000-1500 rounds of magnum ammunition. When end shake reaches about 0.002" the crane arbor would be stretched and adjusted to remove the end shake. This can only be done twice before cylinder gap opens to the service maximum of 0.009". At that point either the barrel must be set back (common gunsmith fix) or a (+) cylinder fitted (usual factory fix) to correct the condition. Usually by this time the cylinder will not carry up correctly in DA fire, and a wider hand is fitted to correct the DCU (doesn't carry up) condition. If the locking notches in the cylinder are also peened, the cylinder stop will be replaced with an oversized one.

Later Model 19s had a small flat machined on the barrel extension at the 6:00 position to clear the gas ring on the cylinder. The cylinder gas ring was moved from the yoke onto the cylinder of later guns to mitigate cylinder binding with use of the Winchester X38SPD all-lead hollowpoint +P .38 Special ammunition (FBI Load). "Hubbed cylinder" guns are not recommended for frequent use with full-charge .357 ammunition. This is because if shot frequently with full-charge .357s the barrel extension will crack through the thin section where it had less heat capacity. Older Model 19s having the gas ring on the yoke, rather than on the cylinder, do not have this problem, but after about 5000 rounds of full-charge magnum ammunition will require both a long cylinder and oversized lockwork parts to stay in specs. Once a gun reaches this point, if it again goes out of time or develops further end-shake, it already has all the oversized parts in it. Factory practice is not to attempt further repair of an OFG (open front gage the factory term noted on the repair-reject tag) and return the gun because no repair parts are available.

Department guns tagged OFG and returned are scrapped.

In extensive testing by US Customs and Border Patrol at the Federal Law Enforcement Training Center in Glynco, GA, it was determined that the K-frame .357s would not pass a 5000 round endurance test of full-charge .357 without malfunctions or requiring replacement parts that required maintenance above the user level."


It certainly is a heckuva .38. If I were going to shoot lots of .357 I'd use my 28-2.

 

[Jonesy814]

Why is it that I always hear warnings that shooting 125gr magnums in a model 19 will eventually crack the forcing cone, but never hear the same warning when it comes to models 13, 65 and 66? They are also K frames with that same flat area at 6:00

 

[entropy]

I feel like arguing that.

You wouldn't if you knew dfariswheel's knowledge level on the subject. I do, and I agree with him. I've seen military Model 10's that had been shot only with the anemic military 130 FMJ .38 Spl. round (yes, lots of them, but not .357's ) that were looser than Betty Lou at the roadhouse on Saturday night. .357's would greatly accelerate the process.

You gotta love it when someone starts a "any Gunsmiths? thread, and then start arguing with them when they answer.

 

[Paul7]

You wouldn't if you knew dfariswheel's knowledge level on the subject. I do, and I agree with him. I've seen military Model 10's that had been shot only with the anemic military 130 FMJ .38 Spl. round (yes, lots of them, but not .357's ) that were looser than Betty Lou at the roadhouse on Saturday night. .357's would greatly accelerate the process.

You gotta love it when someone starts a "any Gunsmiths? thread, and then start arguing with them when they answer.

I've heard over on the S&W forum of Model 14s shot loose after about 8K .38 rounds. Doesn't mean it's a bad gun, anything mechanical has to be maintained.