What is causing these Gouges inside the barrel?

[omcf]

I have a lightweight .357 J-frame revolver (340 PD).

I always clean my weapons promptly after shooting, so this time after the range I noticed that the barrel was really hard to get clean. I was using a standard copper brush and a boresnake. Looking closer, I began to think it was not gunk that would not come loose, but serious gouges on the inside of the rifling.

There were little slivers of metal that would come out (see photo).

It appears the problem is worse on the right hand side of the barrel and only from the forcing cone forward about an inch, then it stops.

I only use factory ammo in this gun, and if I had to guess I would say it has about 2000 rounds thru it since I bought it new in 2004; .38 special and .357.

Can anyone tell me what is going on? I thought this couldn't happen with modern barrels, unless I left...I dunno, sand or something in the barrel before blasting away?

 

[omcf]

more pics....

 

[Yarddog]

Lead IMO
Y/D

 

[243winxb]

Little slivers of lead is my guess also, if using lead bullets.

 

[omcf]

But is that (lead slivers) scratching up the rifling?

And why is the lead getting sheared off to begin with? I obviously would not have fired another round if I had realized the lead slivers were in there, and I have not observed this with any other gun. Although admittedly I do not fire lead bullets other than .22s...

 

[Magnuumpwr]

Have you shot any lead rounds or just jacketed? Do you have any recovered rounds? Post some pics of those if you do.

 

[omcf]

No recovered rounds, but I have shot lead and jacketed.

 

[243winxb]

No lead bullets used, then contact S&W

the problem is worse on the right hand side of the barrel

This may be a timing problem? The barrel is a steel sleeve liner rather than a single solid piece of steel. I think this sleeve has been discontinued? Not sure? I hope its not a problem, as i have a 337PD .

 

[243winxb]

but I have shot lead and jacketed.

Then its lead.

 

[omcf]

If all it is, is lead debris from previous rounds, that is great, easy to fix.

Thank you all for clueing me in to this.

 

[bigfatdave]

Looks like lead buildup to me - are the slivers that come out malleable like lead and colored like freshly-shaved lead?

 

[dogrunner]

Betcha you are using someone's reloads (just because you purchased it doesn't mean it was mfg'd by a major ammo co.)..........the bullet alloy/mix/or lube is the issue and there's really nothing wrong with your gun.

Suggest you change ammo & I'll bet you see a difference.

I shoot a hulluva lotta cast stuff.......full auto as well, and that sort of thing is not an issue with mine. I use straight wheelweights and alox....have for way over 40 years.

If you don't want to change ammo, then just get a lewis lead remover, it'll make cleanup a lot, lot easier.

 

[Dave Bulla]

Look up the "Lewis Lead Remover" unless you are familiar with it already. They work great.

Copper "Chore boy" bronze kitchen scrubbing pads wrapped tightly around a jag work well too but you have to take a magnet to the store with you and test them. Many are steel with bronze plate and not pure bronze. The steel ones can mess up your bore. I'm told the big box stores usually have the plated steel stuff but smaller Mom and Pop type hardware stores usually have the good ones.

There is also a chemically treated patch made by "Lead Away" that works well. It will pull slivers like you show on the Q-tip. No idea how it works, just know it does but you need it to fit tight!

 

[Dave Bulla]

Note, hard lesson learned.

I once got rid of a Ruger 7 1/2" Bisley SBH revolver super cheap because I couldn't make it shoot worth a darn. On cleaning, I could see what looked like a gouged or galled patch in the barrel about an inch forward of the chamber. I cleaned and cleaned but no help. It looked SO MUCH like pitting I was convinced it was. Only in later years did I learn about leading and how to get it out. I still kick myself over that one.

 

[armsmaster270]

I concur with the Lewis Lead Remover.

 

[rbernie]

Can anyone tell me what is going on?

Yes, what you are seeing is lead deposits left from shooting unjacketed lead ammo. It will not harm the barrel, but if you let it build up too long it can cause unsafe chamber pressures from the bore obstruction that it creates.

But is that (lead slivers) scratching up the rifling?

A cleaning brush wrapped in copper (only copper!) wool strands is the easiest way to clean it out. But there is/will be no damage to the barrel from the leading once you clean it out, since the lead is far softer than the steel of the barrel.

Leading happens when the gasses behind the lead bullet are not sealed by the base of the bullet, allowing the gasses to rush past the sides of the bullet. The sides of the lead bullet melt a wee bit, and the lead sticks to the insides of the barrel. This doesn't happen in jacketed bullets since the higher melting point of the copper jacket doesn't suffer from the same effects. You can keep it from happening in the future when using lead bullets by shooting ammo that uses softer alloys for the bullets, and that sizes the bullets to be just a wee bit (one thousand of an inch or so) over groove diameter - these steps will help ensure that the base of the bullet seals properly.

 

[omcf]

Thank you for the cogent explanation of the (apparently common) phenomena I observed, as well as the remedies!

 

[denpython]

I thought those images looked familiar.
Once happened in my .357

Yup, it cleaned out.

hoping for the best!

 

[4v50 Gary]

I like the Lewis Lead Removal Tool. You can also get copper Chore Boy from your grocery store. Wrap that around an old brush and that'll clean out the lead.

 

[rondog]

Also be aware that PLATED bullets may look like jacketed bullets, but they don't perform like them. They're still lead bullets, only with a micro-thin copper plating on them. They have to be fired at lead velocities, they can't handle jacketed velocities.