With the popularity of these guns in this frame why did they stop making them?

With the popularity of these guns in this frame why did they stop making them?

because S&W hates us.

j/k

There has been a rumor going around for many decades. The story says that a K frame will shoot loose after repeated use of heavy full house 357 rounds. I have heard stories of it happening but never shot that many rounds out of any of mine yet. To remedy this, they came out with the ever so popular L framed 586 and 686.

K framed 357s were still made until recent years. They replaced the 65 and 66 with the L framed 619 and 620. From what I can see these 2 newer models have been sleepers compared to the 13,19,65 and 66. Now the K frame is only offered in 38+p and smaller.

So to get to the point, S&W was convinced that the K frame was not tough enough for 357 abuse.
I dont know anyone who shoots a steady diet of hot magnums anyway.

Well . . . I just bought another 1980's era K-frame .357 Magnum lately. IMHO, they are PLENTY strong for me! I LOVE 'em!

I have NO L-frames at the minute . . . much preferring the better pointing, better handling, better looking K-frames.

Then again, beauty is in the eye of the beholder, and LOTS of folks love the more rugged L-frame models too!!!

The K-Frame magnums didn't "shoot loose" as much as they started to incur problems with the barrel/frame juncture under the forcing cone.

Background
The K-Frame was designed in 1899 around the .38 Special's 17,000 psi load using a 158 or 200 grain RNL bullet. This gun, the M&P, later called the Model 10,became the basis for all K-Frames.

In the 1950's, S&W introduced the Highway Patrolman (Model 28, N-Frame) and the .357 Combat Magnum (Model 19 K-Frame). The lighter Model 19 was a fast seller, especially for police officers.

Introduction of light bullets
In the 1960's, responding to the need for more effective .357 Magnum loads for police, Lee Juras founded Super-Vel corporation and produced the first .38 Special +P loads as well as some very hot .357 Magnum loads. At that time, the problem was JHP ammo didn't expand reliably. Juras lightened the projectiles to increase their velocity, using 110gr and 125gr bullet weights. Many police officers used it and reports indicated the 125gr load was quite effective.

The major ammo companies developed their own very fast magnum loads with 110 and 125 grain bullets. Notably Remington's 125g SJHP was an excellent performer at 1500+ fps from a 6" barrel.

At this time, most police departments practiced with .38 Special ammo and officers upgraded to .38 +P or .357 Magnum on-duty. This saved money as well as wear & tear on the issued guns. It wasn't until the late 70's that this changed.

Train as you fight, fight as you train.
The new training paradigm said that officers missed too often in gunfights and one reason was they weren't prepared for the power of the magnum loads. So Police departments started forcing officers to qualify with duty ammo. Of course, this also meant practicing with duty ammo too. As this practice increased, so too did the number of K-Frame .357's experiencing serious problems.

Police armorers noticed a higher frequency of small cracks forming around the forcing cones of the K-frames(Model 13's and 19's). Some of the guns actually showed a cracked frame under the barrel. Essentially the frame split underneath the opening for the barrel.

On the K-Frame magnum, the barrel has a flat bottom cut to allow the yoke to swing the cylinder closed. It was at this point the frame cracks were noticed and frequently, just above that point, cracks in the forcing cone.

Getting to the root cause
The cause is subject to some debate. In a nutshell, the 110 and 125g bullets are much shorter than 140-158gr bullets. Upon firing, the lighter/shorter bullets exit the case and have to "jump" from the case mouth to the barrel (just like 158g). But because they are shorter and the chamber mouth slightly larger than the bullet some of the burning gases flow past the bullet and enter the barrel before the bullet does.

These are very hot gases and they literally erode the forcing cone metal. (In a microscope the metal looks like lizard skin!) The gases aren't shut off until the shorter bullet contacts the the rifling of the barrel. Then the gases are directed up towards the topstrap and out the sides of the cylinder gap. If the bullet strikes the heated forcing cone the repeated impacts can cause cracking of the eroded metal. In contrast, the longer 140-158g bullets stay in the brass a touch longer, lowering the temperature of the gas, plus they block more gas from getting into the barrel because the butt of the bullet is in the flash gap when it contacts the rifling. Less gas gets around and what does flow past is "cooler".

A study of the cracking of the frames below the barrel revealed that over 90% of the guns affected had filthy barrels. Lead build up in the forcing cone, improper hygiene over time and cracked forcing cones.

Precautions for your K-Frame .357's
If you keep the barrel and especially the forcing cone of your K-Frame magnum clean you significantly reduce the chance of failure. It's better to use a heavier weight bullet for most of your shooting too.

S&W's answer was to beef up the K-Frame into the L-Frame. Unfortunately the added that ugly Python-isque underlug to the barrel. A 6" 686 weighs about the same as a 6" N-frame! The 4-inch is only about 2oz lighter than a 4-inch N-frame. No wonder people like to shoot them.

__________________
BillCA in CA (Unfortunately)

Thanks BillCA in Kalifornia for a very good explaination! So i should not expect them to reissue those models ever again I guess that makes the existing ones more valuable.

Some additional comments.

* One should not think of these problems as a "design flaw" in the K-Frame or even the magnum K-frames. Based on the 158g bullets in use in 1955, these guns will withstand a lifetime of .357 Magnum loads.

* There is no problem using the lightweight bullets in .38 Special or even .38 +P cartridges. These don't develop the same heat and pressure of the .357 Magnum.

* With today's JHP's expanding more reliably at lower velocities, it isn't necessary to drive bullets up to 1500 fps. Look for 125g ammo that departs a 4-inch barrel at 1250fps or less. Or if a 6" barrel is used, at 1350fps or less. Heavier bullets can be driven faster - like the 145g Silvertip at 1450fps (4") because the bullet is longer.

* S&W did attempt to "save" the K-Frame magnums. Later Model 66's (-7 models) utilized a slightly beefed up frame and a two piece barrel that eliminated the need for the flat bottom on the barrel.

* If you shoot a lot of lead bullets or you want to guard your investment, buy a Lewis Lead Remover tool and keep your forcing cone free of lead build-up. It does take quite a bit of neglect to build up enough lead, but why take the chance?

__________________
BillCA in CA (Unfortunately)

I always thought the 586 would have been a dandy gun if our friends in Springfield had put a regular barrel on it.

I can accept it as-is, since all the guns I know about have been terrific shooters, but they are sure nothing to look at, compared to a Model 19.