SP101 and flame cutting of forcing cone?

[Monster Zero]

Seems like I read somewhere that the SP101 has the same problem with flame cutting of the forcing cone like K-frames have.

Having just dug out a stash of Winchester 110gr .357 do I need to be careful or can I just go shoot and enjoy it with no worries?

 

[eddiememphis]

Don't worry about the safety of the gun.

It would take many thousands of round to erode the frame enough to be dangerous.

If you are concerned, fire 20 rounds and look at it under magnification. You will likely see no damage.

 

[dannyd]

It's a Ruger, I own two SP's and I have never had any problems with that.

 

[Monster Zero]

Don't worry about the safety of the gun.

It would take many thousands of round to erode the frame enough to be dangerous.

If you are concerned, fire 20 rounds and look at it under magnification. You will likely see no damage.

Thank you both.

 

[Ohen Cepel]

Not trying to be a smart mouth, but I hope to be able to wear out a few guns in my life through honest wear (not abuse). If I had the time (I reload so ammo is less of a concern) to shoot an SP101 to failure (and my hands could take it) I would almost celebrate that milestone.

 

[cfullgraf]

I've shot a ton of 158 gr bullets at full power in my S&W Model 19 over the years and have not seen any flame cutting of the frame. Cracking the forcing cone is a different matter.

But, the S&W Model 19's made before the current production models have an identifiable weakness in the forcing cone design.

I have a 327 Fed Mag SP101 which I have not experienced any problems with. But granted, there is less material in this revolver that is chambered in 357 Magnum.

Just note, you go to a smaller frame gun rated for 357 Mag, it is likely to fail before a heavier frame revolver.

"You pays your money, you take your chances" when operating at the extreme limits.

 

[Dave DeLaurant]

I recall when Ruger came out with the Blackhawk in 357 Maximum and there were concerns about flame cutting the topstrap using hot loads and light bullets, Ruger assured users that the cutting would stop after reaching a certain depth. I don't recall a similar concern about forcing cone cutting or erosion.

The SP101 is stainless rather than blued steel and has a thinner topstrap and forcing cone than the BH so any comparison is probably pointless, but this sparked a memory and at my age I sometimes need reassurance that my memory still works.

You might consider using +P .38 Specials instead of Magnums -- they are loaded to significantly lower pressure.

 

[edwardware]

. . .flame cutting of the forcing cone like K-frames have.

K frames may exhibit cracking of the forcing cone, at the bottom, when fed magnum loads (especially lighter bullet weight loads). Flame cutting of the forcing cone is not a notable issue on K frames or any other revolver I'm familiar with.

Flame cutting of the top strap, above the forcing cone, occurs in almost all revolvers, and is only an issue in few, typically those with non-ferrous frames. For instance, the S&W Scandium .44 Mag has a steel clip to shield the frame at that spot.

In the case of your SP101, it will wear you out before you wear it out, with any sane load.

 

[fxvr5]

K frames may exhibit cracking of the forcing cone, at the bottom, when fed magnum loads (especially lighter bullet weight loads). Flame cutting of the forcing cone is not a notable issue on K frames or any other revolver I'm familiar with.

https://www.ssusa.org/articles/2020/9/28/how-to-avoid-revolver-forcing-cone-failure/

 

[tightgroup tiger]

Last line of the article.
"It might be a good idea to stop shooting high-pressure ammunition in a gun with obvious erosion for the benefit of a longer life."
What happens when you don't shoot high pressure ammo and you still get it. This is my Ruger GP100.

Notice there is no flame cutting above the forcing cone. I haven't shot it enough to even cut the frame.


This was done with low pressure plated and lead bullets. It's still shooting accurately but I will have to have it replace soon. I'm not waiting until it cracks or blows out.
Ruger said if I want it fixed I have to pay for it myself.

 

[edwardware]

What happens when you don't shoot high pressure ammo and you still get it. . .
This was done with low pressure plated and lead bullets.

Looking at that picture, I don't think you have flame cutting. . . I think you need to clean the lead fouling off the barrel face. A brass punch to scrape, and a brass toothbrush to finish.

 

[Onty]

Last line of the article.
"It might be a good idea to stop shooting high-pressure ammunition in a gun with obvious erosion for the benefit of a longer life."
What happens when you don't shoot high pressure ammo and you still get it. This is my Ruger GP100.

Notice there is no flame cutting above the forcing cone. I haven't shot it enough to even cut the frame.

View attachment 1161409
This was done with low pressure plated and lead bullets. It's still shooting accurately but I will have to have it replace soon. I'm not waiting until it cracks or blows out.
Ruger said if I want it fixed I have to pay for it myself.

I asked about same problem on another revolver, as shown on your picture. More experienced folks stated that that could be lead buildup. However, just to be on a safe side, I would stay away from double base powders. They have certain amount of nitroglycerin, and as result barrel forcing cone and aft face, and top strap erosion occurs. I know for a case when a gentleman was shooting very high pressure (his loads) 357 Magnum from FA83, using double base powders. And erosion was clearly visible. He switched to IMR4227 and no further erosion. Vihtavuori powders are excellent in that respect. As far as I could understand their website https://www.vihtavuori.com/powders/ , N100-s, N300-s and N32C powders are single base, N500-s are double base. They cost bit more than others, but folks I know, who are a big time in bullseye shooting, use Vihtavuori N300-s only.

 

[fxvr5]

They cost bit more than others, but folks I know, who are a big time in bullseye shooting, use Vihtavuori N300-s only.

Are they shooting revolvers or semis? And are they doing it for gas erosion or cleanliness and accuracy?

 

[Tallball]

FWIW, I'm 57 and have never put enough wear on a revolver to hinder its function.

The only revolver I even own that has obvious significant wear was made in 1915-16. Its cylinder lockup is a bit loose and the rifling is a bit worn. It still shoots pretty good.

My Sp101's have been stout little revolvers. I wouldn't expect to wear one out in the rest of my lifetime.

 

[Mizar]

Notice there is no flame cutting above the forcing cone. I haven't shot it enough to even cut the frame.

Forcing cone erosion usually starts from the inside edge and slowly progresses to the outside, not like in your picture. Your barrel is fine - this is lead build up that needs to be cleaned.

 

[4v50 Gary]

.357 Maximum was notorious for flame cutting. It's the nature of the beast.

 

[dannyd]

FWIW, I'm 57 and have never put enough wear on a revolver to hinder its function.

The only revolver I even own that has obvious significant wear was made in 1915-16. Its cylinder lockup is a bit loose and the rifling is a bit worn. It still shoots pretty good.

My Sp101's have been stout little revolvers. I wouldn't expect to wear one out in the rest of my lifetime.

I have 13 Rugers and my only after death wish is; Paw Shop dealer telling the family, that the revolvers are all shot out and smooth bore.

Do you realize how many rounds that would take.

 

[mavracer]

Rugers are well built but they don't defy physics.
Their forcing cones will erode, the reason K frames got a bad rap is the early ones had the bottom cut to clear the shroud on the crane. Couple this with high round counts of hot 110 and 125 gr bullets and erosion lead to the thin area cracking.
Erosion is gradual and takes a lot of rounds, the short 110 and 125 heavy loads are worse because they have more powder and the short bearing surface allows the powder and gasses to hit the forcing cone earlier before pressure drops a bit.

Having just dug out a stash of Winchester 110gr .357 do I need to be careful or can I just go shoot and enjoy it with no worries?

How many is in a stash?
1-200 wouldn't concern me
5-10,000 still no for what that ammo cost I can shoot it and see what happens and buy another SP101.

 

[Onty]

Are they shooting revolvers or semis?

Both. SIG P240, S&W M52, and some very nice revolvers like Manurhin MR73 38 Special SAO, S&W M14, S&W 686 standard and Match Champion. Also, folks shooting one of those 357 Magnum Taurus revolvers and I can tell you some are winning. I had see once guy hit 5x10 with Taurus.

And are they doing it for gas erosion or cleanliness and accuracy?

Those are experienced shooter and reloaders, and they know for many years about erosion issue with double base powders. Since consistently getting excellent accuracy with Vihtavuori N300-s powders, they just stick with them. Lately, they started making hollow base bullets from ordinary WC lead bullets, and told me that all fliers are gone. Loads are bit warmer 38 Special, or lower 357 Magnum, velocities about 850-900 fps (minimum required by rules 250 m/s or 820 fps).

 

[fxvr5]

Those are experienced shooter and reloaders, and they know for many years about erosion issue with double base powders. Since consistently getting excellent accuracy with Vihtavuori N300-s powders, they just stick with them. Lately, they started making hollow base bullets from ordinary WC lead bullets, and told me that all fliers are gone. Loads are bit warmer 38 Special, or lower 357 Magnum, velocities about 850-900 fps (minimum required by rules 250 m/s or 820 fps).

This does not sound like bullseye match rules. I see no reference to minimum velocity in their rule book. Please show me where it does in the NRA rule book. Thank you.

 

[tightgroup tiger]

Looking at that picture, I don't think you have flame cutting. . . I think you need to clean the lead fouling off the barrel face. A brass punch to scrape, and a brass toothbrush to finish.

Forcing cone erosion usually starts from the inside edge and slowly progresses to the outside, not like in your picture. Your barrel is fine - this is lead build up that needs to be cleaned.

That did start from the inside and work it's way out and it's not lead build up. It doesn't scrape off. It's cut into the face of the forcing cone. It has shot mostly plated bullets, a few jacketed, and only recently Hi-Tech Coated bullets.
My SP101 is also starting from the inside and working it's way out now. It only has a few hundred rounds shot through it.

I'm not enamored with Ruger barrels on their revolvers. But like I said it still shoots accurately.
This was at 7 yds standing, off hand. I pulled that one shot

 

[tightgroup tiger]

The lead smearing in the forcing cone is from some Lee Tumble Lube bullets that I tried in it and they leaded the barrel badly.
It was something I tried once and had to quit using due to the leading they were causing. I only shot a couple hundred of these and got tired of cleaning lead out of my riflings so I scrapped the lead I was making them out of. There was something wrong with it.
The coated bullets I buy from Brazo's doesn't do that.

 

[Onty]

This does not sound like bullseye match rules. I see no reference to minimum velocity in their rule book. Please show me where it does in the NRA rule book. Thank you.

Sorry for incomplete information, rule(s) mentioned is (are) on another side of a big pond.