K-Frame Forcing Cone

[TGS]

So, let's say I have older Model 19s that I want to keep running for a long time. I generally shoot 38 Special for this reason.

I got a bunch of ammo from work that is essentially a 38 +p version of the "Manstopper" that is infamously harsh on K-frame forcing cones, a 125gr SJHP. It's Winchester X38S7PH, and according to Winchester charts is clocked at 945fps out of a 4" barrel.

Certainly this isn't a crazy hot round or anything of the type, but what's the fps threshold for excessive wear on K-frame forcing cones when shooting 125gr? If I want to keep my 19-4 running as long as possible, should I refrain from using this as my standard practice round?

Commercial loads these days are supposedly lighter than those of the wheelgun golden era, so I imagine even the average modern 357 125gr would give longer service life than what shooters were seeing in the 50s/60s/70s. I'd like this gun to have the rifling wear out before the forcing cone, though...

[mtnbkr]

What is "a lot"?
Do you need to shoot it all in the 19 or can you split it among multiple guns?

I suspect you'd be ok. IIRC, the issue was with the 125gr magnum load, which is significantly hotter than your 125gr +P load. Even if you do manage to wear out the forcing cone before the rifling, you have repair options such as setting the barrel back a bit and having the forcing cone re-cut or having what's known as a "Taylor Throat" performed on it.

Chris

[JAH 3rd]

As much as you love a 19 (I do too), you might consider another revolver to shoot on a regular basis to keep the 19 running as long as possible. A S&W L-frame, 586 or 686 might be considered. They are suppose to be more sturdy in those areas the 19 might be weak. And you would still have that S&W trigger pull you are already familiar with. A Ruger GP100 might be an option. Never shot one, so I can't comment on the trigger pull. But all accounts seem to point to a ruggedly built revolver.

Factory support is a biggie for me. As time goes by, I wonder if S&W will support the older 19's. The lockwork is different on the current 19's as opposed to the older ones. All factory produced products is about production....getting the product out the door. And I am talking about anything factory produced, which is about everything. So if I had a 19 that I wanted to keep running forever, I would find a competent gunsmith. That can be a challenge, but reviews can be found on blogs from people who actually use a gunsmith.

[41magfan]

Even if that load was actually producing the claimed velocity, it wouldn't be considered "hot" IMO. Secondly, the factors that cause wear/erosion to the forcing cone and top-strap aren't just related (in and of itself) to velocity, but the powders used to achieve high velocity and that is usually an issue with the "Magnum" cartridges .... not the .38 Special. But having said that, you may experience a bit more wear and tear with that load (if you shoot it exclusively) than you will one using a lead bullet going a hundred fps slower, but it would take a lot of shooting to discern the difference.

If wear and tear is a huge consideration, make sure you maintain a minimal operating cylinder gap and verify that you have good alignment with regard to timing. Those issues will likely cause more problems than your ammo concerns.

[Zeke38]

Ball powder and a 125 JHP driven at 34K PSI which was the "Manstopper" load built by Federal and Remington back in the day will erode the forcing cone and sometimes crack the barrel. The Winchester 38 +P Special load at 945 won't hurt your weapon. What was occurring with the Manstopper was the light bullet was jumping into the forcing cone with unburnt ball powder flowing in behind it acting as an abrasive.

If you want your 19 to last and be servicable, lead 140-158 bullets at 1100-1200 in Magnum loads with non ball powders like Unique, 2400. These are standard 357 loads and produce a long service life.

But 38+P loads will run for ever. Jacketed or non jacketed slugs.

[willie]

The +p 38 spl load may not damage the Model 19 forcing cone. This cone differs from the Model 15 or 10 .38 Spl. forcing cone. In these, much of the cone extends from the frame barrel juncture and is unsupported. In the Model 19 more of the cone is supported, because a greater part of this barrel section is found within the frame barrel juncture. Hence, not all K frames share the same forcing cone to frame arrangement. In .357 Mag K frames, hot 125 grain magnum ammo was the offender. For some reason, it cracked more stainless forcing cones than blued. As pressures increase, so does throat erosion. Also flame cutting of the top strap increases. The two events occur in all revolvers to some extent.

In S&W K frames, that part of the barrel frame juncture is very thin especially at the bottom section, right above the yoke or crane area. Threads take up much of this space and don't leave much solid thickness. Once in a brand new and unfired .38 Spl K frame, when I fired one factory wadcutter round, this section of the frame split. At this time, the factory product service manager explained K frame dynamics to me. This guy was the same one who sent me a working copy forming the basis of much of Roy Jinks' book. Jinks was the company's historian. Monday I'm sending this original document to Stephanie. My friend gave it to me over 40 years ago.

Shoot and enjoy your Model 19. Buy a used beater for parts. The gun will outlast you.

[TGS]

Secondly, the factors that cause wear/erosion to the forcing cone and top-strap aren't just related (in and of itself) to velocity, but...

The Winchester 38 +P Special load at 945 won't hurt your weapon. What was occurring with the Manstopper was..

Great info from you and 41magfan. Totally what I was looking for, thanks!

As much as you love a 19 (I do too), you might consider another revolver to shoot on a regular basis to keep the 19 running as long as possible. A S&W L-frame, 586 or 686 might be considered. They are suppose to be more sturdy in those areas the 19 might be weak. And you would still have that S&W trigger pull you are already familiar with. A Ruger GP100 might be an option. Never shot one, so I can't comment on the trigger pull. But all accounts seem to point to a ruggedly built revolver.

I used to own all of those.

If I wanted to shoot one I would've re-bought one, or not sold it to begin with.

What is "a lot"?
Do you need to shoot it all in the 19 or can you split it among multiple guns?

This is a "beater" gun that was a throwaway gunsmith special and brought back to life. It is being shot in order to keep my retired agency gun in near mint condition. Even if I do get another Model 19, I'm just trying to make prudent decisions about what to shoot through them with regularity...so getting more guns isn't necessarily the answer to the question anyway.

"A lot" is however much ammo I can get from my agency while I remain in their employ; figure, 200 rounds a quarter or so. It's free ammo, so I'll shoot however much they give me.

[Totem Polar]

Shoot and enjoy your Model 19. Buy a used beater for parts. The gun will outlast you.

This.

Everyone has already said what I’d say about the 125 grain SJHPs going 1450fps being a different phylum, let alone animal, from the .38 125 loadings. At 6-800 rounds of .38 +P a year, It’ll outlast you.

[oregon45]

If it truly is a "beater" gun, and if the ammo is free, then just shoot it all and see what happens. 19-4's are not particularly uncommon.

[HCM]

So, let's say I have older Model 19s that I want to keep running for a long time. I generally shoot 38 Special for this reason.

I got a bunch of ammo from work that is essentially a 38 +p version of the "Manstopper" that is infamously harsh on K-frame forcing cones, a 125gr SJHP. It's Winchester X38S7PH, and according to Winchester charts is clocked at 945fps out of a 4" barrel.

Certainly this isn't a crazy hot round or anything of the type, but what's the fps threshold for excessive wear on K-frame forcing cones when shooting 125gr? If I want to keep my 19-4 running as long as possible, should I refrain from using this as my standard practice round?

Commercial loads these days are supposedly lighter than those of the wheelgun golden era, so I imagine even the average modern 357 125gr would give longer service life than what shooters were seeing in the 50s/60s/70s. I'd like this gun to have the rifling wear out before the forcing cone, though...

Unless there is some inside info on this particular .38 load, I think you are confusing your agencies 125 grain +p 38 load with the old school 125 grain .357 mag loads. It was the magnum loads that were infamous for being harsh on K frames.

That gun should outlast you shooting +p .38.