Can a mod 15 frame take the pressure of 357...
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The model 14 barrel should not be an issue at .357 pressures, and 'probably' not the model 15 frame either.
However, fitting a .357 cylinder means shortening the forcing cone for the longer part, beveling its bottom to clear the longer yoke, making sure it times correctly...I think it might be better to try out full pressure .38 Special like Buffalo Bore first and see if that cures the case of magnum-itis.
If after all is said and done you still have your heart set on an 8 3/8" .357, S & W may have made one or two of those also
. Good luck on your decision.
However, fitting a .357 cylinder means shortening the forcing cone for the longer part, beveling its bottom to clear the longer yoke, making sure it times correctly...I think it might be better to try out full pressure .38 Special like Buffalo Bore first and see if that cures the case of magnum-itis.
If after all is said and done you still have your heart set on an 8 3/8" .357, S & W may have made one or two of those also
. Good luck on your decision.
In addition to the thoughts above I think it is somewhat dependent on the era the Model 15/14 parts were manufactured in. After all metallurgy changes over time
No way would I consider this if using a Model 15 from 1957
I might be comfortable with donor parts from the 1990s
I would be totally comfortable if using one of the late Model 15s from 2002
No way would I consider this if using a Model 15 from 1957
I might be comfortable with donor parts from the 1990s
I would be totally comfortable if using one of the late Model 15s from 2002
Jcon72
Member
I'm no gunsmith so excuse the dumb question, but is the frame strength really anything to worry about in this case? Considering the prolific use of K-frames in .357 it seems to me that the cylinder would be the main concern pressure-wise, and of course a model 19 cylinder was built for said pressures.
Charlie Foxtrott
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If you need to you can really load a .38 Special round up hot enough.
To where you are looking at +/- magnum ballistics. So why bother?
To where you are looking at +/- magnum ballistics. So why bother?
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Assuming the other parts stay together, a K frame .38 Special may have been built differently than a .357 in terms of heat treatment and the like. Frame distortion/stretching in this situation would be a concern; there is a recent thread about this occurring with model 38 Airweights and + P use, not exactly the same situation but analogous.
How moderately loaded? How many rounds? How much do you care if the gun gives out on you?
Both Alliant and Hodgdon have recipes for .38 Special loads going 1000 to 1050 FPS. Or use Vihtavouri powder. Their reloading app has a variety of 158 grain loads doing 1000 to 1100 FPS. Using the right powder can get you recipes are hotter than many 357 Mag starting loads.
Or If I thought it was necessary to do, I'd just load up some 38/44 loads and use them sparingly.
Both Alliant and Hodgdon have recipes for .38 Special loads going 1000 to 1050 FPS. Or use Vihtavouri powder. Their reloading app has a variety of 158 grain loads doing 1000 to 1100 FPS. Using the right powder can get you recipes are hotter than many 357 Mag starting loads.
Or If I thought it was necessary to do, I'd just load up some 38/44 loads and use them sparingly.
Having made several model 10 and 15 frame into 357s by using model 19 cylinders and having had zero problems, I say it is no problem at all for modern frames. Cylinders blow up not frames.
I have also measured a bunch of K frames and the model 19, 15 and 10 are basically the same. I even have a hardness tester and those readings are the nearly identical on every steel S&W I have tested N and K 357, 44 mag, 45 ACP, 38 and even an old 1917 frame.
Get a clue, they make scandium alloy J frame 357 magnums. Not only do J frames have smaller sectional areas in critical spots like the top straps, but also the complete side and front of the frame, than a K frame has in those same areas. Not only do they now make steel J frame 357s they make them with Scandium alloy. The very best and strongest scandium/ magnesium/ aluminum alloy Al,6Mg,0.5Sc has a tensile strength of 433MPa and a yield strength of 503Mpa. S&W frames only show 2% Mg when shot with a PMI gun, so they are under that more like a yield of 376MPa and a tensile of 401 MPa. Heat treated hot rolled 4140 straight from the mill has a tensile strength of 1075 MPa and a yield of 852MPa. Non heat treated from the mill has a yield of 415 and a tensile of 655. Still stronger than scandium alloy. PS any place that deals with much alloy steel will probably have a PMI gun.
Please explain to me why a steel K frame frame isn't strong enough to handle 357 mags, when a smaller J frame one made with Scandium alloy one will.
Show me a blown up frame with an intact cylinder. There have been a lot of 38 special K frames made into 357s. Show me the ruined frames.
By the way the very first one I did was a model 10-2 It has had a lot of 357s ran trough it at this point and it still has the same minimal end shake it had when I set it up. IF it had any frame stretch it would have some
Also remember the first fix sight K frame 357s were just 10-6 frames with 357 cylinders prior to the model 13.
Some people actually do some do research and actually try it.
I have also measured a bunch of K frames and the model 19, 15 and 10 are basically the same. I even have a hardness tester and those readings are the nearly identical on every steel S&W I have tested N and K 357, 44 mag, 45 ACP, 38 and even an old 1917 frame.
Get a clue, they make scandium alloy J frame 357 magnums. Not only do J frames have smaller sectional areas in critical spots like the top straps, but also the complete side and front of the frame, than a K frame has in those same areas. Not only do they now make steel J frame 357s they make them with Scandium alloy. The very best and strongest scandium/ magnesium/ aluminum alloy Al,6Mg,0.5Sc has a tensile strength of 433MPa and a yield strength of 503Mpa. S&W frames only show 2% Mg when shot with a PMI gun, so they are under that more like a yield of 376MPa and a tensile of 401 MPa. Heat treated hot rolled 4140 straight from the mill has a tensile strength of 1075 MPa and a yield of 852MPa. Non heat treated from the mill has a yield of 415 and a tensile of 655. Still stronger than scandium alloy. PS any place that deals with much alloy steel will probably have a PMI gun.
Please explain to me why a steel K frame frame isn't strong enough to handle 357 mags, when a smaller J frame one made with Scandium alloy one will.
Show me a blown up frame with an intact cylinder. There have been a lot of 38 special K frames made into 357s. Show me the ruined frames.
By the way the very first one I did was a model 10-2 It has had a lot of 357s ran trough it at this point and it still has the same minimal end shake it had when I set it up. IF it had any frame stretch it would have some
Also remember the first fix sight K frame 357s were just 10-6 frames with 357 cylinders prior to the model 13.
Some people actually do some do research and actually try it.
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JohnHL
Member
Would it be possible to simply bore the 38 cylinder a little deeper to the 357 mag chambering?
Would it be long enough?
John?
Would it be long enough?
John?
Ya, you could and it has been done. There I might have a bit of concern if the cylinder was very old. I find it hard to imagine that using modern methods there is any cost benefit to using steel with a inferior heat treatment for 38 special cylinders. But, Model 19 cylinders are not that hard to find or fit. The big bonus it a shorter barrel shank sticking through the frame. Shorter means stiff and in my opinion less apt to crack. I have never paid even $100 for a recessed model 19 cylinder. In fact there are several of them on Ebay right now for $75 buy it now. A reamer cost more than that and just renting one will be over $50 once you pay shipping both ways. The 357 cylinders are only 0.10 longer on K frames.
On the whole deal about making 10, 14, 15 etc into 357s, I would expect a 10,14 or 15 frame to last about as many rounds of 357 as a 19. But, remember that actual model 19s and 13s will never stand up to anywhere near as many 357 rounds as a 28 or 27 N frame or even a 586 or 686 L frames That is why the L frames exist. The K frame is more lightly constructed simple as that, but still way heavier than any J frame
On the whole deal about making 10, 14, 15 etc into 357s, I would expect a 10,14 or 15 frame to last about as many rounds of 357 as a 19. But, remember that actual model 19s and 13s will never stand up to anywhere near as many 357 rounds as a 28 or 27 N frame or even a 586 or 686 L frames That is why the L frames exist. The K frame is more lightly constructed simple as that, but still way heavier than any J frame
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Go get yourself a Model 19.
38 Special loads.
I've seen some load data from an old Lyman manual (1967) that will produce 1000 FPS using 2400, a powder that is a mainstay for loading .357.
I know that doesn't address your question, but what velocity are you trying for with your .357 conversion? I would first ask that question before making any conversions. 1000 fps is a crackin 38 spl. load using a 158 gr bullet. The load data says 11.0 grns of 2400 will get you there. Also Unique but you need to look at the load data before you try it. Don't take my word for it.
I've considered doing that for a K frame. I have a model 28 for the high pressure/high velocity 357 loads. I don't load those for my model 19's anymore. Just beats me and the gun up too much. Personally I think the 19 was an ill advised frame size for high pressure 357 loads. JMO. YMMV.
http://www.nzha.co.nz/wp-content/uploads/2015/08/Lyman44.pdf
I've seen some load data from an old Lyman manual (1967) that will produce 1000 FPS using 2400, a powder that is a mainstay for loading .357.
I know that doesn't address your question, but what velocity are you trying for with your .357 conversion? I would first ask that question before making any conversions. 1000 fps is a crackin 38 spl. load using a 158 gr bullet. The load data says 11.0 grns of 2400 will get you there. Also Unique but you need to look at the load data before you try it. Don't take my word for it.
I've considered doing that for a K frame. I have a model 28 for the high pressure/high velocity 357 loads. I don't load those for my model 19's anymore. Just beats me and the gun up too much. Personally I think the 19 was an ill advised frame size for high pressure 357 loads. JMO. YMMV.
http://www.nzha.co.nz/wp-content/uploads/2015/08/Lyman44.pdf
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Thanks for the information, it reassured me to what I was fairly sure of. BTW, ain't my first or will be my last K,L or N fram Smith. Will be the first I put together myself, for a multiplex load developed for large lizzard eradication.
SuperMan
Member
..gotta love people with common sense based on real world experience...
Buffalo Bore and Underwood Ammo both have .38 Special ammo that are rated for J-frames that are far beyond what the Big Three are willing to make... There is no reason that the old .38-44 loads can't be used in a post-WWII K-frame. If you look in the 1950s vintage SHOOTERS BIBLE under Colt listings, the steel frame Detective Special was rated for "HIGH VELOCITY .38 Special"... .38-44 loads...
That said, there is one weak point...the unsupported barrel shank that extends into the frame that does not with the Model 19/65.... I have seen two crack when fed a constant diet of heavy jacketed bullet loads. Have never seen a cylinder go or frame stretch...
Bob
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key, board, got, wet, , get, an, , when, hit, space bar, LOL
key, board, got, wet, , get, an, , when, hit, space bar, LOL
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scooter123
Member
I've been a Manufacturing Engineer since 1982 and one thing we DO NOT LIKE is a scheme where identical components have different materials and/or heat treats. To the point of pounding on some VP's desk. Because it will universally lead to those parts getting mixed and then recalled for that problem. I expect that the K frame has evolved to different material specifications and heat treatment throughout it's service life but when the 357 Combat Magnum first appeared it was based on the then standard K frame without any change to it's heat treatment. Because there is NO DIFFERENCE in the cost for heat treating to a "lighter" standard and most heat treatment operations will refuse to do something like this simply because it's too easy to get these parts mixed up.
As for the material specifics, I suspect that the frame are not heat treated at all. Instead S&W relies on a high strength Forging Steel and the work hardening in critical areas in produced by the forging process. At most these frames may go through a Stress Relieving process to minimize "creep" over time due to internal stresses. I also expect that the cylinders go thru a similar scheme except that it's forged bar stock and that may a pre-hardened stock, something that is a very low cost option for forged steel bar. Where I work a common steel for certain type of tooling is 4140 PHT at a hardness of 28-32 Rockwell C. This is a easily machined steel with a high yield strength that can provide an extended service life for low pressure forming dies.
Steelslaver, in post #10 you said you have a hardness tester. I've never heard of that. Is it anything like an eddy current test? We used to have a guy come in and check our chilled water and condenser tubes using an eddy current test, but that was for the wear and thickness of the copper tubes and the steel shells. (Ammonia systems used all steel.)
I really like to hear of tools that I don't have, so I know they're out there if I need one! (If I don't learn some obscure fact once a day it means I didn't wake up. This morning I learned my debit card has been compromised for $8.97. Dang thieves!)
I really like to hear of tools that I don't have, so I know they're out there if I need one! (If I don't learn some obscure fact once a day it means I didn't wake up. This morning I learned my debit card has been compromised for $8.97. Dang thieves!)
The points have been pretty well covered. However, a historical note. When the model 19 was developed, the general practice was to use .38's for the vast majority of shooting. Some LEAs went so far as using .38 wadcutter target ammo for practice and qualification. The magnum loads were reserved for duty use. I'll also note that depending upon departmental requirements, an individual might retire in 20 years with his service revolver firing slightly over 2000 rounds total.
Aided by the Newhall incident and other factors such as unexpectedly greater recoil, muzzle flash & blast with the full power loads, training was generally changed to full power ammo all the time. Training requirements generally increased. Given the relative high round count, the k frame started to show excessive wear. This resulted in the L frame development.
The entity I joined in 1988 issued the 681 and Federal 125 gr JHP .357 ammunition. We trained a lot and the guns did suffer, becoming loose and often required returns to the factory when the armorers couldn't cope. No idea how many rounds it took.
So, the question really becomes, just how long/much do you want to be able to shoot really stiff loads out of your model 14?
The hardness testers I've seen use a device to press a specified form against the test metal to a given pressure. The configuration of the deformation of the tested material determines the hardness. The rating method generally used on gun steels is the Rockwell C chart. A quick search for a tester found one for only $1253.00 US and I'm not sure that's the entire unit.
Aided by the Newhall incident and other factors such as unexpectedly greater recoil, muzzle flash & blast with the full power loads, training was generally changed to full power ammo all the time. Training requirements generally increased. Given the relative high round count, the k frame started to show excessive wear. This resulted in the L frame development.
The entity I joined in 1988 issued the 681 and Federal 125 gr JHP .357 ammunition. We trained a lot and the guns did suffer, becoming loose and often required returns to the factory when the armorers couldn't cope. No idea how many rounds it took.
So, the question really becomes, just how long/much do you want to be able to shoot really stiff loads out of your model 14?
The hardness testers I've seen use a device to press a specified form against the test metal to a given pressure. The configuration of the deformation of the tested material determines the hardness. The rating method generally used on gun steels is the Rockwell C chart. A quick search for a tester found one for only $1253.00 US and I'm not sure that's the entire unit.
