Smith and Wesson new K-frames forcing cones

[dave_the_swede]

Hey guys I've heard about the older K-frame .357's having their forcing cone split after a steady diet of full powered 125 grain loads, I was wondering if S&W ever got this ironed out since they re-introduced some of their K-frame classics?

 

[Drail]

Even if a steady diet of 125 gr. magnums doesn't split or crack your cone it will flame erode the heck out of it. The ones that cracked on the old K frames did so because the cone was cut very thin on the bottom to clear the crane. If your cone is full thickness all the way around it won't split but those hot fast loads are still greatly accelerating wear and tear on the cone. Any load that creates a large fireball in front of the muzzle will cut a forcing cone like a oxy-acetylene cutting torch. It's always been that way. I ruined a GP 100 runing lots of 110 gr. screamers through it. The forcing cone has deep black grooves burned in it and rounded corners from that. And that gun had a thick heavy forcing cone. My advice is to stick with 140 gr. or heavier moderate velocity loads if you want the gun to last. I have also seen guys ruin the forcing cone on S&W 696 .44 Spl. L frames because they insisted on running 180 gr. high velocity screamers through it. The forcing cone on a 696 was very thin to enable S&W to thread a big bore barrel into a medium bore frame. When I was young and dumb I loved shooting the flame thrower loads but I finally grew up and realized it was just stupid. Now I only shoot big heavy slow bullets and they work just fine.

 

[Kendal Black]

There is an interesting discussion with pictures to be found here. https://thefiringline.com/forums/showthread.php?t=542727

The redesign was in answer to the problem you mention, but with Drail I will mention that hot loads with light bullets are bad news generally.

 

[cfullgraf]

S&W has done a redesign of the Model 66 that should eliminate/reduce the chance of cracking the forcing cone. I'm not sure the dash number of the updated design but it came out within the last year or two.

Flame erosion may still be an issue as Drail has said.

I cracked the forcing cone on my 1980 vintage Model 19 shooting a steady diet of 158 grain full power 357 Magnum loads so be fore warned. I was using the revolver in IHMSA silhouette competition.

Fortunately, at the time, circa early 1980s, S&W replaced the barrel on their dime. Don't expect that service these days as I understand barrels are no longer available.

 

[Drail]

Silhouette shooting eh? I'll bet those were some healthy loads if they'd knock that ram down. Bangin' and clangin'.......

 

[NIGHTLORD40K]

Starting with the M19-9, they redesigned the front cylinder latch, this allowed them to eliminate the flat cut on the barrel extension and it's inherent weak spot.

My M19s never see Magnum loads:
......its not worth risking a cracked barrel. I consider them to be .38 Specials with the ability to fire .357s in a pinch.

If you want to shoot lots of Magnums, skip the M19 and get a 686. Problem solved!

 

[Old Dog]

I'm not sure how much one has to shoot to crack or split the forcing cone on a K-frame, and as far I'm concerned, flame-cutting on the topstrap is simply a cosmetic issue. I've fired probably thousands of full-house .357 rounds through a 66-1, 66-4, two 19-3s, a 19-4 and a 19-7. While all exhibit evidence of flame-cutting, for years I fired hot .357 rounds in almost every range session through my K-frame .357s because, well, the internet in its current incarnation with these wonderful gun forums didn't exist, hence I knew nothing about the proscription against firing lighter, hotter loads from my revolvers. Seems a lot of the internet revolver shooters must shoot way, way more than I do ...

 

[NIGHTLORD40K]

I'm not sure how much one has to shoot to crack or split the forcing cone on a K-frame, and as far I'm concerned, flame-cutting on the topstrap is simply a cosmetic issue. I've fired probably thousands of full-house .357 rounds through a 66-1, 66-4, two 19-3s, a 19-4 and a 19-7. While all exhibit evidence of flame-cutting, for years I fired hot .357 rounds in almost every range session through my K-frame .357s because, well, the internet in its current incarnation with these wonderful gun forums didn't exist, hence I knew nothing about the proscription against firing lighter, hotter loads from my revolvers. Seems a lot of the internet revolver shooters must shoot way, way more than I do ...

I think it's almost exactly like the old M1903 Springfield dilemma- you might shoot one of those a hundred times a day for a century and never have an issue, then one day......BOOM.

Stress risers, frame stretching, materials, production dates, heat treating, round count, bullet weight and velocity.....all probably play a part in determining which 19 barrels will fail and which never will.

Of course a cracked forcing cone is far less severe than a shattered receiver, but now that repair parts are largely unavailable any more, both will result in a ruined and worthless firearm. I won't risk it with mine when there are plenty of .357 L and N frames around......which are darn nice guns in their own right.

 

[kscharlie]

Regarding the older S&W Model 19s, what many people forget is that the 19 was created well before the advent of really hot 125 grain loads. It was designed around the "standard" 158 grain loads. I will not, under any circumstances, shoot any .357 loads other than 158 grain in my 19-4. If I want to shoot the hot loads, I get out my DW 15-2.

 

[Zaydok Allen]

I cracked the forcing cone on my 1980 vintage Model 19 shooting a steady diet of 158 grain full power 357 Magnum loads so be fore warned.

Interesting. I was always under the impression that it was the 125's and 110's that really damaged K frames. This is the first time I've ever heard anyone state that 158's wrecked a gun. Though they must have been warm and frequent given what you were using the gun for.

I am hoping to start loading 357 magnums soon using 158's and 180's with H110. They'll be shot out of L frames though and I don't compete or gun game at all. So I should be fine.

This topic always makes interests me.

 

[cfullgraf]

Interesting. I was always under the impression that it was the 125's and 110's that really damaged K frames. This is the first time I've ever heard anyone state that 158's wrecked a gun. Though they must have been warm and frequent given what you were using the gun for.

Hot 125 and 110 grain 357 Magnum loads have probably cracked more forcing cones than the 158 grain loads only because more of the lighter bullets have been fired out of Model 19 or Model 66. I bring up that hot 158 grain loads can crack a forcing cone because I'd hate to see someone wreck a nice old Model 19 or Model 66 that is now virtually impossible to repair these days.

I was shooting IHMSA silhouettes with the gun, a 6" Model 19. At the time, it was the only gun I had that was remotely suitable for the game. For the 200m rams, I had enough adjustment in the S&W sights where I could still place the sights on the ram to knock them down.

Lots of practice and many matches. The rounds were loaded to max but not over max.

The barrel failed during a sighting in session the day before a match.

So that I could shoot the match, I pressed my Model 25-5 into service with standard 45 Colt loads (I do not hot rod ammunition for any gun). To hit the rams, I had to aim about 20 feet over top of the rams. You almost could fire the gun and eat lunch before the bullet got to the target. I even knocked one ram over during the match on the bounce.

S&W repaired the Model 19 on their dime. I bought a 10" Contender chambered in 357 Magnum to shoot silhouettes. (The Contender stretched the budget at the time so adding a new cartridge to my shooting mix was not in the cards).

Apologizes for side tracking the thread.

 

[Zaydok Allen]

Hot 125 and 110 grain 357 Magnum loads have probably cracked more forcing cones than the 158 grain loads only because more of the lighter bullets have been fired out of Model 19 or Model 66. I bring up that hot 158 grain loads can crack a forcing cone because I'd hate to see someone wreck a nice old Model 19 or Model 66 that is now virtually impossible to repair these days.

I was shooting IHMSA silhouettes with the gun, a 6" Model 19. At the time, it was the only gun I had that was remotely suitable for the game. For the 200m rams, I had enough adjustment in the S&W sights where I could still place the sights on the ram to knock them down.

Lots of practice and many matches. The rounds were loaded to max but not over max.

The barrel failed during a sighting in session the day before a match.

So that I could shoot the match, I pressed my Model 25-5 into service with standard 45 Colt loads (I do not hot rod ammunition for any gun). To hit the rams, I had to aim about 20 feet over top of the rams. You almost could fire the gun and eat lunch before the bullet got to the target. I even knocked one ram over during the match on the bounce.

S&W repaired the Model 19 on their dime. I bought a 10" Contender chambered in 357 Magnum to shoot silhouettes. (The Contender stretched the budget at the time so adding a new cartridge to my shooting mix was not in the cards).

Apologizes for side tracking the thread.

I guess it's a blessing it didn't fail in the middle of the match.

I like my reloads and hand loads warm, but usually stop 2 10ths of a grain shy of max loads. No need to abuse a gun if I'm not competing.

Like I said too, I don't shoot any older K frames. Good info here though, none the less.

 

[LUCKYDAWG13]

Not to hijack but should i be concerned about shooting my 686-3 A lot with mid range loads of Unique

 

[cfullgraf]

Not to hijack but should i be concerned about shooting my 686-3 A lot with mid range loads of Unique

One of the reasons for S&W introducing the L-frames was to correct the limitations of the K-frames shooting 357 Magnums.

The L-frames will handle a steady diet of full power loads. The frame and cylinder on the L-frames is a bit larger than K-frames. The grip frames are the same though.