Borescope revelations

[Someoldguy]

I purchased a borescope recently, and just as everyone warned me, I've seen plenty of things I was previously unaware of. Perhaps I'm naive yet, given the time frame and small barrel pool I have to work with, but it appears some patterns are emerging already.

I've a couple of barrels, in particular, that I've worked with extensively, yet accuracy has been elusive. Over 1 MOA always, and well over 1 MOA at times. Many of you would have given up already, and this thread will only aggrevate you if you read further. So don't say I didn't warn you.
Now, being that I am intrigued with the . . . . mystic surrounding barrel accuracy, I have persisted. Load development, scope changes, bedding changes, bench techniques, all seemed to offer promise temporarily, but ultimately proved a waste of time.
Enter the bore scope. The barrels /rifles I own that shoot well with minimal effort also produce minimal copper fouling. And the barrels producing 'challenges' copper foul significantly, and rapidly.
As I do not subscribe to coincidence, I presume the 2 are related, particularly given the information relayed in many postings on this very forum.

I have also discovered another disturbing fact. Prior to my possession of a bore scope, I would have vehemently and vigorously denied the suggestion of rust damage to any rifle bore that I own. However, I must now accept the fact that, while undetectable to the naked eye during frequent visual inspections, I do, in fact, have rust damaged bores. And the damage is present in the 2 rifles I've been struggling with.

So, this post is mostly a question. Of those of you who own a bore scope, have any of you found previously undetectable bore damage from rust? And if so, have you found it detrimental to accuracy?

And have you found any solution to the problem, apart from barrel replacement?

Thank you for your time. I'd appreciate any CONSTRUCTIVE input anyone should care to offer.

Have a good day!

 

[jkohler]

Borscopes can make good shooting guns stop shooting. I don't even like to look in mine anymore. But I occasionally still do.

 

[spclark]

I had two Lothar Walther stainless barrels chambered in 6.5 Grendel in which I found what could have been evidence of rust / corrosion and/or metallurgical flaws in the making of them. I'd had both for awhile before buying a Hawkeye, used moly-coated bullets in both too.

What I saw looked like short pieces of string or twine but etched into the lands & grooves closer to the muzzle than the breech.

I'd always taken great care not to leave the bores unprotected by a coating of oil either when I had to put off cleaning for a period after shooting, or after cleaning.

Neither barrels shot poorly though, or coppered badly. Both barrels went on to new owners, neither one complained about their performance.

 

[Jet]

Using a bore scope I've never seen rust in my barrels. I do monitor throat erosion, carbon, etc. with it. Also handy to inspect inside your brass. Some folks love them, others refuse to place them in their bores. Bottom line is the target will almost always be the best judge of what is going on. The scope helps provide info that you can use to make decisions on how to proceed in the quest for smaller groups and higher scores.

Good shooting.

Rich

 

[Someoldguy]

I'd like to be able to blame what I'm seeing in these 2 cases on the manufacturer. But the reality is, I've seen the same damage on the EXTERIOR of too many firearms to deny what it is. Evidently, some barrels corrode more easily and/or some powders are more corrosive. Or I'm just simply not attentive enough.

 

[Someoldguy]

Using a bore scope I've never seen rust in my barrels. I do monitor throat erosion, carbon, etc. with it. Also handy to inspect inside your brass. Some folks love them, others refuse to place them in their bores. Bottom line is the target will almost always be the best judge of what is going on. The scope helps provide info that you can use to make decisions on how to proceed in the quest for smaller groups and higher scores.

Good shooting.

Rich

I agree. If the darn things shot well, I could care less what they looked like. Unfortunately, they shoot rather poorly, and I'd like to determine PRECISELY why, if possible.

 

[rayjay]

IMO, every SERIOUS competition shooter should have a bore scope. I wonder how many tons of bullets and powder has been wasted trying to make a bbl shoot decent groups that one look with a bore scope would have put and end to the efforts. Slugging is also another skill that can pay dividends. I recently tried out an idea for accurately determining twist rates using lead slugs and the factory bbls would go stiff and loose several times as the slug was pushed down the bore. The PacNor, Shilen and other bbls would be totally smooth all the way down. It's got me interested in lapping the factory bbls.

 

[ridgeway]

If a barrel doesn't shoot, most likely a borescope isnt going to tell you why. Sell the borescope and buy more barrels, lol

 

[hoz53]

I agree. If the darn things shot well, I could care less what they looked like. Unfortunately, they shoot rather poorly, and I'd like to determine PRECISELY why, if possible.

the only thing i have seen that seems to correlate with accuracy are chambers not concentric with the bore. Fairly common in factory rifles -mine at least-- Ive got an egyptian FN-49 thats so bad its hard to see the groves but it shoots pretty good for what it is. All just my Humble opinion

 

[Someoldguy]

If a barrel doesn't shoot, most likely a borescope isnt going to tell you why. Sell the borescope and buy more barrels, lol

This seems to be a common response, but I have a hard time accepting it. I can't believe there isn't a reason, or perhaps more appropriately multiple reasons, that barrels aren't accurate. Either way, I am aware of a problem with my cleaning and storage that I wasn't before.

 

[Alex Wheeler]

I use a bore scope often. I have had a few barrels that did not perform, the bore scope showed no issue. I would say the vast majority of issues are steel related. Its my opinion that the barrel is destined to be a good one or a dud before the bore is even drilled. I have had some bad manufacturing, loose spots, barrels performed excellent. As far as I am concerned the steel is 99% of the barrel. One of the reasons I dont jump on these small barrel shops. Krieger has buying power, the little guys do not. I am sure they do excellent machine work, but you have got to get the best steel.

 

[rayjay]

This seems to be a common response, but I have a hard time accepting it. I can't believe there isn't a reason, or perhaps more appropriately multiple reasons, that barrels aren't accurate. Either way, I am aware of a problem with my cleaning and storage that I wasn't before.

Don't accept it. Same guy would probably tell you that a lathe and milling machine are useless because you can't learn to do anything yourself.

 

[hogpatrol]

It would be helpful if you could provide some additional information. What kind of rifle barrels are you talking about? Chromoly? Stainless? Factory? Custom? If it's an off the shelf factory rifle, what caliber & manufacturer? If you have rust and you didn't put away your rifles wet, you have a humidity/storage issue and that also needs to be addressed. My rifles are never stored with a dry bore an oiled bore or if going to be used soon, a patch of Hoppes. I borescope for checking cleaning, throat and machining issues.

 

[L.Sherm]

I use a bore scope often. I have had a few barrels that did not perform, the bore scope showed no issue. I would say the vast majority of issues are steel related. Its my opinion that the barrel is destined to be a good one or a dud before the bore is even drilled. I have had some bad manufacturing, loose spots, barrels performed excellent. As far as I am concerned the steel is 99% of the barrel. One of the reasons I dont jump on these small barrel shops. Krieger has buying power, the little guys do not. I am sure they do excellent machine work, but you have got to get the best steel.

I agree with Alec's statement on steel for making barrels execpt the 99% If they are not drilled properly that's were the tight and loose spots come from, as you machinists know feed rate and speeds are everything. Lapping process and proper bore and groove dimensions are also key. The steel is the foundation to a good barrel but if the other processes are not done correctly it's all for not. Good steel will not make up for bad machining.

 

[X Ring Accuracy]

I agree with Alex, it's the steel. There are times when feeding a reamer by hand, different consistencies in the steel can be felt.

 

[Alex Wheeler]

I agree with Alec's statement on steel for making barrels execpt the 99% If they are not drilled properly that's were the tight and loose spots come from, as you machinists know feed rate and speeds are everything. Lapping process and proper bore and groove dimensions are also key. The steel is the foundation to a good barrel but if the other processes are not done correctly it's all for not. Good steel will not make up for bad machining.

Maybe the best shooting barrel I ever had, had a loose spot in front of the chamber. It was so bad you could feel it just with a patch. It would foul heavily in that spot. Shot my first 4" 10 shot group at 1k with that barrel, and it would shoot .2-.3 at 200 yards. I do think good steel makes up for a lot. I have seen more than one barrel with machining defects shoot like that.

 

[Someoldguy]

It would be helpful if you could provide some additional information. What kind of rifle barrels are you talking about? Chromoly? Stainless? Factory? Custom? If it's an off the shelf factory rifle, what caliber & manufacturer? If you have rust and you didn't put away your rifles wet, you have a humidity/storage issue and that also needs to be addressed. My rifles are never stored with a dry bore an oiled bore or if going to be used soon, a patch of Hoppes. I borescope for checking cleaning, throat and machining issues.

I sent you a PM. about specifics. I live in Missouri, and today it's 101º and the reported humidity is an astonishing 94%. I thought I was doing a sufficient job of cleaning and oiling my firearms, and they are stored in a heated and air conditioned room.
But clearly, I'm going to have to change what I'm doing. At least now I know there is a problem. Before, I was just blissfully unaware.

 

[L.Sherm]

You have a very good point Alex, I think sometimes people put to much in what they see in a borescope. In my opinion the target tells the true story. You can have the best barrel in the world but a crappy chamber job and its probably gonna be just so-so, unfortunately almost always the blame gets put on the barrel.

 

[Ggmac]

The Borescope has its place , it's a tool not a fortune teller ! I can see carbon build up in a friends rifle or check his fantastic cleaning procedure and show him the barrel isn't bad just a good cleaning . Down here in south Florida , I see a lot more stainless barrels with surface rust as opposed to chrome moly . I think it boils down to the stainless owners don't think they rust and therefor don't protect . I will say that those that protect , both chrome and stain less , surface rust begins the minute they stop shooting 90 deg and about same humidity , stick the HOT rifle in a case , then into an AC car then into the AC house . Condensation starts in a few minutes , yes I checked and showed shooters that packed up and hung around talking . They were amazed , so now I carry a fogging oil made for storing motors , spray while warm , bore and outside . Then dry clean and respray after temp has normalized in my house .
Most of my stuff ( practical not pretty ) gets a normal finish and painted on the exterior . I use to use electro less nickel , but my connection moved .
Think WW2 British weapons , blued or parkerized and painted .
More after nap

 

[Someoldguy]

I agree with what has been stated above, I'm not going to worry about a good shooting barrel no matter what I *think* is wrong with it. Poor shooting barrels is what I'd like to find the cause for.

Around here, on a day like this, all you have to do is step outside with a firearm and it is immediately coated completely with condensation.

Hate to stay off range all summer, but perhaps that's what I need to do.

But, is the general consensus that these 2 barrels would likely not shoot well even without the light corrosion damage?