Fairly new SS .900 barrel pitting.....?

[winxp_man]

So I have 277 rounds down the tube of a custom SS barrel .308 Win Cal. (at this time I would rather leave brand name out) I got the rifle re-barreled back in 2016. Yea got a few firearms and between shooting and fishing it gets tough to do it all haha. But After getting a bore scope I have noticed pitting at the last 2-3" of the barrel. Now to say that it might be something I have done cant say its not impossible... But I do that back up to the idea here. I own another in 300 WM from the same exact barrel company with about the same amount of rounds down the tube and not a pit in it. The 300WM was giving me .20's-.30's MOA with 210 Berger PPU Ammo. They are kept in the same exact place next to each other. And both have been shot in the same conditions and all match ammo. I dont believe in wasting a barrel on shit ammo.

SO what gives for the pitting? I'm really confused. As for shooting both are under .5 moa easily. My first group was .34 moa at 100. After that group I decided lets try some cleaner for copper maybe it was copper somehow left behind in weird ways. So after cleaning it all went to shit and grouped where 1moa. At first I though maybe run a few rounds to foul the barrel a bit. But ended up putting about 30 rounds and it was still putting the rounds in 1 moa. Maybe a few more rounds to foul the barrel till it shoots where it was before? Either way can't say what caused the pitting and if its what is effecting the groups till the pits fill in..... Might give the barrel company a call. I will post some pics that I captured from the bore scope.

 

[z28kid]

Curious as well, have a 6 and 6.5 creedmoor that has some near muzzle too.

 

[Superjet]

Steel worms...

I don’t know the exact cause for this, but most likely it is from the rifling process or small voids in the steel that are exposed by boring and rifling.

Is the barrel cut or button rifled? I have a button barrel that looks worse, but is one of the best shooters I’ve ever had. Your accuracy will come back after it fouls again.

 

[Steel head]

My current 260 barrel has that.
It’s been an excellent shooter so it’s a non issue for me.

 

[Newbie2020]

I was told this can happen more with button rifled vs cut rifled barrels. The buttoning exposes weak spots within the steel.

 

[winxp_man]

Well glad to see others have seen this. And its not only me. I will add more info as fouling starts to build a bit. Either way the rifle is a shooter. As long as this does not spread out to ruin the barrel I'm good with it. I will keep an eye on it and see how the copper fouling goes with the the pitting in the first pic that one seems to grab a bit more copper. Again hope it does not decide to extend.

 

[Newbie2020]

If @Steel head says it’s ok, then it’s ok.

Shoot the crap out of it, then start over.

 

[z28kid]

Both of mine are cut rifled

 

[flyright]

Bore worms. They've always been there but now everyone has a borescope. If it shoots well, forget about it.

I'd hate to be a barrel maker these days. Better get a dedicated line or two for new borescope users...

 

[RTH1800]

These threads are worthless without name of barrel maker.

 

[seanh]

Why? All that would do is create bashing by some of the Fanboys.


I agree with what's been said... If it's a shooter put it out of your mind. Don't worry about it.

 

[winxp_man]

Why? All that would do is create bashing by some of the Fanboys.


I agree with what's been said... If it's a shooter put it out of your mind. Don't worry about it.

Agreed! And its why I didn't post a name without talkin to them first. I will still call them to get an opinion from them. My real concern is if these said worms will spread towards the front of the barrel. I will continue to shoot it at this point, and see how it goes.

 

[RTH1800]

What is the purpose of thread if not to o identify poor quality barrel and maker?

This barrel will obviously foul more quickly and have a shorter service life.

We are getting far too sensitive.

if you make a barrel that chunks fall out of you need to be exposed.

 

[seanh]

The sensitivity is coming from those that feel the need to know the manufacturer name. OP just has a curiosity question.

I think people are glossing over the most important aspect of the original post... don't clean your gun when it fucken shoots. Found that out the hard way with my old Remington Barrel... which by the way looked like the pictures posted in a few spots through the barrel.

 

[Superjet]

What is the purpose of thread if not to o identify poor quality barrel and maker?

This barrel will obviously foul more quickly and have a shorter service life.

We are getting far too sensitive.

if you make a barrel that chunks fall out of you need to be exposed.

“Expose” a mfg for making a barrel with a few strange marks that shoots well? How do you know it will quickly and have a shorter service life? If you had a borescope you’d be surprised what you can find in a “good” barrel.

 

[RTH1800]

I have had a borescope for 20 years. Examined hundreds of barrels. Most were factory barrels or cut rifled barrels by Krieger, Schneider or Bartlien. Absolutely none had chunks falling out

If a barrel with chunks falling out of the lands were offered as an option would you buy it? At full price? At a steep discount? I would not take it as a gift.

I had one barrel with a large void on the outside when turned to diameter. Likely unsafe. It was a Shilen. I never used one again. Speaking the truth is not difficult. Why would you protect a company that sells faulty products?

 

[z28kid]

The 6 creedmoor cut rifled barrel I have shoots great and would have never looked in it if not to compare it to the 6.5 creedmoor I was having accuracy issues with. Both are different barrel makers, both top tier.
Again both cut rifled, both have what looks like small amounts of pitting near the muzzle. The 6.5 was found to copper fouling much easier and seems to be the cause of the accuracy loss and the pitting has nothing to do with that because it is fouling all the way down the barrel and seems to need cleaning after every range trip to keep a acceptable level of accuracy.

The only 4 groups I shot last Friday with the 6 CM, I can't ask for anything more from it.
Well, maybe to last 3000 rounds. Lol

 

[RTH1800]

I suspect that the premature copper fouling is a lesser degree of the pitting issue. All related to bore surface finish or overall poor QC.

 

[b6graham]

put the borescope away and shoot it

.34" at 100 sounds good to go to me

 

[Mark Buettgen]

Hey Guy's, That's not pitting, it's corrosion. Even if it's Stainless, because it has carbon in the mix, it can still rust and corrode.
Could be from several different things, often it's a wet bore and the rifle was left in the case, use of a water based cleaning product left in the bore, etc.---
Later, Mark Buettgen
Bartlein Barrels Inc

 

[z28kid]

Good to know, it doesnt seem to affect anything in my rifle so I wasn't really worried about it.

 

[Steel head]

What is the purpose of thread if not to o identify poor quality barrel and maker?

This barrel will obviously foul more quickly and have a shorter service life.

We are getting far too sensitive.

if you make a barrel that chunks fall out of you need to be exposed.

My current 260 barrel With that has approximately 2500 rounds through it now
I’ve cleaned it maybe 4-5 times and it’s currently lobbing 130’s at 2975 and never has had a copper problem.
It’s been a fantastic barrel as have the others from that manufacturer.

 

[GBMaryland]

Who made it?

 

[winxp_man]

Hey Guy's, That's not pitting, it's corrosion. Even if it's Stainless, because it has carbon in the mix, it can still rust and corrode.
Could be from several different things, often it's a wet bore and the rifle was left in the case, use of a water based cleaning product left in the bore, etc.---
Later, Mark Buettgen
Bartlein Barrels Inc

I have kept it right next to another rifle I had rebarreled. And both same location. Cleaned it once with hoppes elite spray and a bore snake. And this rifle has these worms, while the other does not. Only reason I even busted out the scope is to see the diff in a custom barrel and a couple of my Ruger RPR rifles.

I got a hold of the barrel company and they told me that if I noticed accuracy problems or other problems starting to develope that they would take care of it 100%. So they are standing behind their product and will fix it if need be.

 

[b6graham]

sounds like a good compromise. but i don't expect you'll need that service from them based on how it shoots unless it starts to really get worse

my suggestion. shoot it out soon haha since it's working as is

 

[winxp_man]

Who made it?

I will post the barrel maker name. Being they will stand behind their product 100% from what they told me when I spoke with them on the phone. Its Benchmark Barrels. And for future builds I will still be using them for sure.

 

[tuckybill]

yeah I looked down a SS AR barrel made by kreiger that I adn't cleaned in like 5 months due to a injury. Had a big glob of red rust in it. I was amazed. Shoot fine and you have to know here to look to see the pitting. I'll be much more carful with my SS barrels now. SS ain't as S as it used to be seems like.

 

[Greg Langelius *]

I've seen it and didn't like it; but also been amazed at how well some looking that way still shoot. My 70 y/o Garand with the 60 y/o barrel comes to mind. You don't even have to look inside most Mosin-Nagants 91/30's to find pitting since they used corrosive priming in the hands of peasant conscripts who frequently lost their cleaning rods straightaway.

In the service 50 years ago, we were taught that pitting came from leaving rifles uncleaned. Damp conditions and carbon/copper fouling can corrode/erode bores, but modern primers/propellants, and better barrel steels should have that sort of stuff under pretty good control. But moisture and fouling can still combine electrochemically and act in a way that's similar to EDM machining.

Even stainless will corrode if left uncleaned for long enough. Be aware that Stainless has a nickel component usually 8-10%, which is vulnerable to dissolving in some bore cleaners, including Hoppe's #9. How this affects bores is hard to estimate. For instance, it's wise to keep Hoppe's #9 away from nickel plated gun surfaces, it can strip the plating over time.

There's a fad afoot to minimize cleaning and extend cleaning intervals; but this stuff can still happen. In your case, I suspect that there was copper in the pit and removing it exposed the pit. You may see some relief from allowing copper to reaccumulate.

I'm thinking fouling and humidity, and/or a flaw in the steel blank is the likelier cause..

When you call on the Barrel maker, have those bore scope pictures handy; but don't expect a slam-dunk, especially if the cleaning has been let go over much of the barrel's life. They'll probably ask; and if they accept a return, they'll likely be able to tell whether you were accurate about such stuff.

Greg

 

[winxp_man]

When you call on the Barrel maker, have those bore scope pictures handy; but don't expect a slam-dunk, especially if the cleaning has been let go over much of the barrel's life. They'll probably ask; and if they accept a return, they'll likely be able to tell whether you were accurate about such stuff.

Greg

I'm super picky about how I clean and leaving any kind of cleaner in the barrel for a long time. And the barrel only has 277 rounds through it. Over agreed. I will see in a couple of days what goes on after putting some reloads through the barrel. Thanks for the input brother.

 

[Brux]

I'm dealing with one right now with the same problem. It would not group until you shot 35 or 40 rounds through it. It got sent back and a new barrel got sent and is being chambered now.

 

[JeffLebowski]

put the borescope away and shoot it

.34" at 100 sounds good to go to me

This.

 

[seanh]

I have kept it right next to another rifle I had rebarreled. And both same location. Cleaned it once with hoppes elite spray and a bore snake. And this rifle has these worms, while the other does not. Only reason I even busted out the scope is to see the diff in a custom barrel and a couple of my Ruger RPR rifles.

I got a hold of the barrel company and they told me that if I noticed accuracy problems or other problems starting to develope that they would take care of it 100%. So they are standing behind their product and will fix it if need be.

Exactly why I like that you didn't mention their name. Sounds like everything's getting squared away

 

[Dai Bando]

Bore scopes are a worry warts dream come true.

 

[seanh]

Yep. I know a local shop that stopped for scoping barrels specifically because of that. I was told that the shop went from Maybe two or three warranty issues a year, if that, to dozens.

 

[JeffLebowski]

Bore scopes are a worry warts dream come true.

Exactly.