Is this a carbon ring or other issue in my barrel?

[tsu45]

This barrel only has 250 rounds on it but I started getting more erratic velocities. The timing also coincides with the brass now being once fired versus virgin, so there is another variable there. At first eyeball look into the bore I thought it was pitting, but I started getting some small chunks out while cleaning. The bore-scope pics are in the first couple inches of rifling.

Have my first ever two day match in OK next weekend, worried I have issues with barrel going into that.

 

[CShooter92]

A carbon ring is just as it sounds. It's a literal ring around the barrel pretty much right at the end of the chamber. This isn't a carbon ring.

Literally the only good use for a borescope in my opinion is checking for a carbon ring. Don't look any further. Id investigate your now once fired brass as the culprit to your velocity issues.

 

[spife7980]

Thats a normal barrel thats been fired. Its not your problem.

Sounds like you need to tune your load up with the brass in its new condition.

 

[...]

1) throw the bore scope away.
2) you arent going to have any significant erosion in 250 rounds.
3) discrepancies in velocity were likely due to your reloads.


goodness, everyone buying borescopes then acting like a god damn metallurgist.....that 1 slight imperfection in your rifling isnt why you missed the target.

 

[smoothy8500]

but I started getting more erratic velocities.

Aside from your ES/SD concerns, are your reload's precision still the same at 300yds? If yes, carry on and deal with load development later.

 

[JeffLebowski]

That's a line from normal shooting, not a ring. These borescopes are getting out of hand.

 

[Mordamer]

This barrel only has 250 rounds on it but I started getting more erratic velocities. The timing also coincides with the brass now being once fired versus virgin, so there is another variable there. At first eyeball look into the bore I thought it was pitting, but I started getting some small chunks out while cleaning. The bore-scope pics are in the first couple inches of rifling.

Have my first ever two day match in OK next weekend, worried I have issues with barrel going into that.

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I believe we will both be at the same match next weekend if it is the Okie Showdown.

My advice is to not worry about your barrel. Stop cleaning it and get at least 5 fouler shots through it before the match. You don't have time at this point to worry about your load or nonsense like that. Just load ammo and bring it. If you are having overpressure issues as part of your erratic velocities then do the reasonable thing and back off your powder charge.

Rather than dink around with loads and worry about your velocity statistics, practice dry firing on positional shooting every night for about 30 minutes between now and the match. The number of people at PRS matches that spent dozens of hours dialing in their load to 1/4 MOA with single digits SD's, but can't shoot for crap off anything except prone is pretty high. If you can call the wind decent and shoot well from unstable positions you'll end up with a good score regardless of your ES and SD.

My name is Austin Buschman. I'll be at the sight in day in the afternoon. If there is any way I can help you prepare for the match on sight in day then let me know and I'd be happy to help.

 

[Steel head]

Barrel is trash
Send it to me for proper disposal.

 

[Winny94]

Borescopes in the hands of non 'smiths are the plaugue of modern precision shooting.

 

[sgtsmmiii]

Try annealing your brass before the next resizing to help settle the erratic velocities..

 

[Jaxdialation]

Borescopes in the hands of non 'smiths are the plaugue of modern precision shooting.

Interesting perspective. I think the arrival of $50 borescopes going to do nothing but advance the knowledge of shooters. They can assess their own barrels and the results of their cleaning practices. What we're seeing now is a large number of people asking about what they are seeing, and what it means. It is no different than any other innovation in this sport.

This isn't rocket science, it is just new.

 

[JeffLebowski]

Interesting perspective. I think the arrival of $50 borescopes going to do nothing but advance the knowledge of shooters. They can assess their own barrels and the results of their cleaning practices. What we're seeing now is a large number of people asking about what they are seeing, and what it means. It is no different than any other innovation in this sport.

This isn't rocket science, it is just new.

I think it’s hypochondriacs being handed a medical encyclopedia.

 

[Winny94]

I think it’s hypochondriacs being handed a medical encyclopedia.

Worse - its the hypochondriacs discovering Wed MD. Same info....just faster

 

[jrpilot]

Once fired brass will change things up. Some rifles and chambers more than others. Some rifles I got very little change and on my 338 EDGE i had to lower the charge weight .5 to get the previous FPS and then it was the same accuracy and single digit SD spread.

 

[NiteQwill]

Worse - its the hypochondriacs discovering Wed MD. Same info....just faster

My day job is medicine... I've come to realize WebMD provides me with job security. It's a great website to convince you that you're dying, yesterday...

 

[BigJimFish]

Damn guys, give the guy a brake. It's an honest question, and I think a good one.

To answer you OP. You do have a bit of hard carbon in the barrel. It looks thin and not problematic to me and does not look like the dreaded carbon ring. I expect your erratic velocities have more to do with reloading the once fired brass than the barrel. You might have an issue where you not getting a consistent even lube application on your resizing and perhaps you are getting too much variation in the sizes of your cases after resizing or some other reloading issue. I don't think it is carbon in the barrel.

Now for my rant. It seems to be popular to bash bore scopes and those using them. Cheap, functional bore scopes are new and it is obviously going to take a while for the knowledge base to catch up and help people process what they are seeing. There aren't a whole lot of good pictures, videos, etc. yet to help people process what they are seeing so they often make the wrong judgement and do stupid things like polish their barrel until it looks smooth and then the bullets stick to it and copper foul something awful. Eventually, borescopes will be close to ubiquitous and there will be enough good articles on interpreting the images that people will not freak out over a bit of crackling or try to polish things smooth. Long range shooters are a mostly intelligent, informed, and prone to tinker crowd. A leave it to the professionals attitude is not really in keeping with the spirit of the community.

When it comes to carbon and cleaning. I frankly disagree with a lot of what you might call the consensus thinking around here and think that it contributes to the prevalence of carbon build up problems. Sometimes I get the impression reading here that you should only clean every 300 rounds at the most and then should really only do a few passes with patches around a plastic brush. Fuck that. You want a recipe for carbon problems, shoot small, high velocity cartridges with lots of powder like maybe 6CM and then clean them rarely and with a worthless plastic brush. We are press fitting metal projectiles out the barrel 65k+ psi and 3kfps but people are worried about a flexible bronze brush at 1fps. Ridiculous. You are not going to wreck your barrel cleaning it with a bronze brush every hundred rounds or even more often than that. You are also not going to run into carbon problems if you do because bronze brushes are pretty good at scraping it free before it gets super super hard when you regularly clean with them. It is easier to ruin a barrel with harsh solvents or abrasive cleaning products especially if you are doing long soaks than it is to do so with bronze brushes. I say clean with bronze brushes, patches on spear jags, good ball bearing cleaning rods, rod guides, gentle non-abrasive solvents, no extended soaking, and do this pretty often to prevent problems from getting started.

 

[Jaxdialation]

Damn guys, give the guy a brake. It's an honest question, and I think a good one.

But it's so much easier to poop on a question than answer it. See how many words it took you to explain this?

My day job is medicine... I've come to realize WebMD provides me with job security. It's a great website to convince you that you're dying, yesterday...

Study Suggests Medical Errors Now Third Leading Cause of Death in the U.S. , Source: Johns Hopkins

 

[NiteQwill]

But it's so much easier to poop on a question than answer it. See how many words it took you to explain this?



Study Suggests Medical Errors Now Third Leading Cause of Death in the U.S. , Source: Johns Hopkins

Let's be at least forward with the context, since you want to bring it up. Most deaths in medicine are not due to a single individual error, it's generally a system error (big reason we do time outs before a procedure or when a nurse gives a medication, for example). So, frankly... The KNOWLEDGE of medicine is superb, it's execution always has room for improvement. Relying on a website to give you a diagnosis (webMD) is often dark humor among all those in health care.

The researchers caution that most of medical errors aren’t due to inherently bad doctors, and that reporting these errors shouldn’t be addressed by punishment or legal action. Rather, they say, most errors represent systemic problems, including poorly coordinated care, fragmented insurance networks, the absence or underuse of safety nets, and other protocols, in addition to unwarranted variation in physician practice patterns that lack accountability.

 

[Jaxdialation]

Let's be at least forward with the context, since you want to bring it up. Most deaths in medicine are not due to a single individual error, it's generally a system error (big reason we do time outs before a procedure or when a nurse gives a medication, for example). So, frankly... The KNOWLEDGE of medicine is superb, it's execution always has room for improvement. Relying on a website to give you a diagnosis (webMD) is often dark humor among all those in health care.

The researchers caution that most of medical errors aren’t due to inherently bad doctors, and that reporting these errors shouldn’t be addressed by punishment or legal action. Rather, they say, most errors represent systemic problems, including poorly coordinated care, fragmented insurance networks, the absence or underuse of safety nets, and other protocols, in addition to unwarranted variation in physician practice patterns that lack accountability.

If you'd carry out your quote further, you would have included the fact that medical error related deaths are under-reported.

It doesn't matter how the hell medical professionals kill people - they do it.
You drew the parallel between bore scope users and people who use WebMD.
Further you went on to brag about how much money you make off of WebMD users. Post this at your office? Nah, I didn't think so.

Do you track how many patients figure something out on their own using WebMD and properly DON'T seek professional care?
Nope. But that wouldn't be any fun.

That's what Teslong users are doing - they are attempting to understand the bore of their rifle.
The OP asked about what he was seeing with his (probably new) borescope. You choose to gloat about your earnings, and insult your patients.

Welcome to the brave new world Sir, where people do their best to avoid dealing with assholes by learning on their own. You can (1) help them, or (2) brag about how much money you make, or finally (3) don't read their posts.

 

[FALex]

Can you define "erratic?" Are you sure it's not just your rounds speeding up now that the barrel has a couple hundred through it?