S&W K forcing cone ??????

[MMCSRET]

I see and even read a few threads on cracked and cracking forcing cones on model 66 and model 19 357 Magnums.
Do the same problems appear in the other K frames; Models 13, 65, in 357 magnum?
I've never heard or read of it, why not?

 

[Oyeboten]

Cracked Forcing Cones can occur on Model 10s or earlier K-Frames.


I think it is quite rare, but, with enough of the operatively correct kinds of abuse, it can happen.


Hardball, or too hard of Lead Alloys in home-loads, might have something to do with it, if someone shoots enough of them.

 

[18DAI]

In 39 years of shooting, buying, being issued, competition, and examining literally thousands of different K-frame magnums, I've seen one cracked forcing cone in person. It was two years ago. My gunsmith had a snubby 19-5 come in with one.

I own dozens of K-frame magnums. I shoot 158 grain 357's through them, and I clean them afterwards. I've yet to "shoot one loose", or crack a forcing cone.

I am puzzled that you haven't read about this alleged "issue" with the K-frame magnum. Every newb who buys a 19 or 66 usually frets about it and posts asking if "brand X 357's are ok to shoot through their model 19?"

The L-frame fans always mention this alleged "K-frame magnum flaw" as the reason S&W came out with the L-frame. They never seem to be able to explain why S&W continued to produce the K-frame magnum right alongside the L-frame for twenty plus years, but no matter.

On the internet I've seen photos of cracked forcing cones. All the guns pictured were model 19-5's. They were also filthy dirty. The 19-5's were also the first 19's to get crush fit barrels. IMO S&W took awhile to get that cost cutting measure right.

That, combined with poor or nonexistant cleaning, and the use of hot light weight (125 grain ) 357's is what causes cracked forcing cones, IMO. YMMV.

I never have heard of it happening with the stainless K-frame magnums. Maybe carbon steel isn't as tough? I seem to recall someone here posting about seeing an LEO model 13 with a cracked cone. TJ

 

[rcmodel]

Yes, the chance of a cracked forcing cone would be exactly the same on the other fixed sight .357 Mag chambered S&W models.
The barrel shank, gas ring relief cut, and forcing cone are exactly the same on all of them.

On a well maintained gun, that chance is pretty slim.

I think the reason we hear more about it on Model 19 & 66's is because Internet rumor blows it way out of proportion on 19's & 66's.

3/4 of the people repeating the Internet rumor don't know what a Model 13 or 65 is!!

combined with poor or nonexistant cleaning, and the use of hot light weight (125 grain ) 357's is what causes cracked forcing cones, IMO. YMMV.

ZActly!
Most cops shot a gazillion .38 Special rounds to practice & qualify with.

Then cranked off a cylinder-full of Super-Vel 125 grain Magnums to see what it was like. Without cleaning the leading out of the forcing cone first.

Then loaded another six rounds for duty carry and put it back in the holster.

rc

 

[SaxonPig]

Never heard of any 38 Special revolver doing this, only the 357s. I don't think it was a problem on the stainless guns. Nor on the fixed sight models, either. The stories I have heard all (or nearly all) involved the Model 19. Specifically, the 19-5.

This made #76 on my list of 100 FAQs.

-------------

K Frame S&Ws with .357 Magnum ammo?

76. There are many stories about Model 19s cracking the forcing cones. Actual guns observed failing in this fashion are relatively few. But it does happen. One police armorer stated that he saw a number of such failures and noted that all of the guns were dirty. His theory is that accumulated carbon deposits can create “hot spots” that may damage the barrel upon firing (so keeping the barrel spotlessly clean might eliminate the problem). He observed that several of the guns failed using 158 grain 357 ammo and one M19 cracked from using .38 Special ammo which sort of undermines the popular belief that it is the hot 125 grain loads causing the problem. I have noticed that a large percentage (certainly most if not a preponderance) of the failed guns were 19-5s. These were crush-fit barrels rather than the earlier pinned models. I suspect that these new barrels were often defective in material or installation, causing the cracking. I have a 2.5” M19-3 made in 1970 and carried by a federal officer for 18 years. When I bought it, he said it had never been fired with anything other than 125 grain full Magnum loads and that’s all I shoot in it. So far, no problems.

 

[rcmodel]

I concure.

I only remember seeing one K-38 with a cracked forcing cone.
It had a barrel packed completely full of 148 grain Wadcutters started from a squib load.

The guy kept shooting it until the cylinder couldn't turn any longer, then brought it to the AMU shop for us to fix it.

rc

 

[MMCSRET]

Kind of mirrors my own unqualified opinions. I've owned and used K frames off and on for 40 years and have never witnessed the horrid "CRACK". When I said I had only read a few stories it meant that I got tired of them and passed without reading any more. I just inherited a 66-5, 3 1/4", round butt and a model 65-1. I've had and used only blued guns previously. Thanks to all!!!!

 

[evan price]

THe "K" frame magnums can crack the forcing cone in the underside (6 o'clock) position where it is relief cut for the crane. Basically to get this you need to shoot A LOT of ultra-high-velocity Magnums (the 110 and 125 grain) to do this. I personally have only seen ONE cracked forcing cone ever; that was in a non P&R Mod. 19, and iirc it was also pretty flame cut in the topstrap. The forcing cone was badly "elephant-skinned" meaning it had a lot of high pressure gas abuse.

I personally prefer the 158-grain bullets anyway; most revolvers' sights are regulated for them. I have shot thousands of 158 grain Magnum loaded bullets in "K"-frame S&Ws with zero ill effect, except to the target, which tended to develop holes around the center area.

 

[BurninBrass]

Hey guys. I found a good article on this subject and wanted to share it.

http://www.gunblast.com/Butch_MagnumLoads.htm

By the way, I have 2 Model 19's. A 2-1/2 blued 19-3 and a nickel 4" 19-3. I just picked up the nickel model LNIB so I cannot speak of the abuse it's taken but have shot alot of heavy loads in the blued one I've had for years. I was advised a long time ago to stick to a 80-90% diet of 38 Special and mild 158 grain magnums. 10% use with the hotloads. This has worked well for me.

 

[rscalzo]

Most cops shot a gazillion .38 Special rounds to practice & qualify with.

Then cranked off a cylinder-full of Super-Vel 125 grain Magnums to see what it was like. Without cleaning the leading out of the forcing cone first.

Then loaded another six rounds for duty carry and put it back in the holster

In the old days, yes.

For the last twenty years (at least in NJ), qualification ammo must be identical or politically identical as certified by the AG's office. While free to use lower power ammo to practice on their own of non-qual. sessions is fine, any official qualification session must be conducted using full power ammo.