I borescoped an unused cut rifled barrel: help me learn about what I'm looking at.

Edds

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I don't know what caused those marks but I know what I would do with it.

I would contact the person I bought it from and ask for a quality barrel or a refund. If they wouldn't provide either, I would have someone cut the end of it off and re-crown it.

Then I would tell everyone who I bought it from.
 

TheOfficeT-Rex

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    For everyone saying "shoot it and return it if it performs poorly," have you returned a poor shooting barrel? I don't imagine it to be an easy case to make, at least compared to attempting to return an unused barrel with bore scope pictures.
     

    308pirate

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    I'm LOL at this fucking thread

    The blind leading the blind with one exception and that exception's name is Green.
     
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    Supersubes

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    There is no way to really tell without getting hands on , cleaning the tube and using good equipment to look at it. Cameras can make things look weird and cheap cameras are even worse.

    All machine work looks like ass from the right angle or under the right magnification. Even gauge blocks look like /\/\/\/\/\/\/\ under magnification. That is physics and chemistry.

    Tool marks are just a nature of the process. Would we like to see less? Sure. You can do everything right using the best equipment, tooling and process and still get a chip under a cutter that will drag. Should the gunsmith eat the cost of the barrel? LOL.

    People have no idea what the insides of their tools look like. If everyone took a borescope or optical comparator to their parts no one would shoot becuase they would be too busy bitching on the internet.

    There are soo many variables that go into a how a tube shoots that trying to say because this one may look shity, it won't perform is a non starter.

    Shoot it. Do people not understand what the word "Lapping" Means? Its possible those marks will get knocked down or smoothed out with rounds down the tube like MOST of the marks you don't see that are still there.

    Like has been said, there are plenty of tubes that look pristine but shoot like dogshit and plenty of tubes that look like dogshit that are absolute lasers.

    You don't know until you put the rounds downrange.
    Youre wrong, the land tops should not have “railroad tracks” (as Frank called it) across them. The OP can do whatever he wants, but this isnt some gee golly shit happens thing. Done right, this doesn't happen. Its a mistake that was missed and made it out of the shop.
     

    308pirate

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    For everyone saying "shoot it and return it if it performs poorly," have you returned a poor shooting barrel? I don't imagine it to be an easy case to make, at least compared to attempting to return an unused barrel with bore scope pictures.

    You could just as easily be told "it meets our specs" and you get to eat the fucking barrel.

    Most of you don't know shit from shinola about machining anything but here you are borescope experts
     

    Alan Warner

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    A few words to all you guys.
    I've looked at a shitload of barrels over the past 35 years, and I can tell you that images are not the end all. Some of the most miserable looking tubes are hummers and there is no discernable reason why. Oclusions, pits, supher voids, ---- all kinds of weird shit would make you think this is junk. Maybe, but not for sure.
    Why do you think the top BR shooters buy and chamber 10,or 12 barrels prior to the season and sell all but 3.,, Because those 3 show up on targets what is a good one
    There is no hard and fast quantifying visual inspection of a barrel that says "this is a good one".
    I've had hummers that aided my HMcard
    A pleasure to shoot cause they always printed inside of call. They showed no discernable visual deviation from all,others
    Just shoot the fucking thing and then tell me your classification before you spout off about mostly what you hav'nt a fucks worth of a clue.
     

    Supersubes

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    A few words to all you guys.
    I've looked at a shitload of barrels over the past 35 years, and I can tell you that images are not the end all. Some of the most miserable looking tubes are hummers and there is no discernable reason why. Oclusions, pits, supher voids, ---- all kinds of weird shit would make you think this is junk. Maybe, but not for sure.
    Why do you think the top BR shooters buy and chamber 10,or 12 barrels prior to the season and sell all but 3.,, Because those 3 show up on targets what is a good one
    There is no hard and fast quantifying visual inspection of a barrel that says "this is a good one".
    I've had hummers that aided my HMcard
    A pleasure to shoot cause they always printed inside of call. They showed no discernable visual deviation from all,others
    Just shoot the fucking thing and then tell me your classification before you spout off about mostly what you hav'nt a fucks worth of a clue.
    Alan, nobody is claiming it wont shoot. The OP has said he’s going to shoot it, which is great. He wanted to know what he was seeing. So whats he seeing? There are more than a few in this thread that do this kind of work, including me. Thats not supposed to look like that in my experience. Do yours look like that?
     

    demolitionman

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    Youre wrong, the land tops should not have “railroad tracks” (as Frank called it) across them. The OP can do whatever he wants, but this isnt some gee golly shit happens thing. Done right, this doesn't happen. Its a mistake that was missed and made it out of the shop.
    I thought those were marks from the little bull dozers grouser tracks that the smith must have used to cut the barrel.....
     

    jakelly

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    If my $350 barrel comes to me looking like that it’s going back. I do not care how it shoots. If it’s 1/2 MOA, it should be 1/4. 1/4 MOA it should be in the ones. How it shoots is irrelevant when someone clearly made a mistake.

    That pitting / blemish in the barrel I don’t care about, but that Allen wrench they used for a pilot was the wrong size.
     

    Huskydriver

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    Alan, nobody is claiming it wont shoot. The OP has said he’s going to shoot it, which is great. He wanted to know what he was seeing. So whats he seeing? There are more than a few in this thread that do this kind of work, including me. Thats not supposed to look like that in my experience. Do yours look like that?
    I agree I wouldn't waste a single primer on that tube.

    Not a single one of my golf bag full of wintac chambered bartlein 5rs have any tool marks left in them when they arrive to me. All perfectly lapped everytime.

    I always check before screwing the barrel on to get a baseline of what the throat looks like new.

    If the op was going to shoot it, I would def show the smith first and clearly let him know I would try to shoot it first but if it didn't group I would be expecting a refund not another barrel.

    If that hurts peoples feelings...tough my business is going to a different smith.
     

    Alan Warner

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    Alan, nobody is claiming it wont shoot. The OP has said he’s going to shoot it, which is great. He wanted to know what he was seeing. So whats he seeing? There are more than a few in this thread that do this kind of work, including me. Thats not supposed to look like that in my experience. Do yours look like that?
    I've seen a lot worse looking than that shoot in the ones
    Winchester made a bunch in the 80- 90 that looked a bit better than my rear exit sewer that shot in the 2,s and 3,s.
     
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    Huskydriver

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    I've seen a lot worse looking than that shoot in the ones
    Winchester made a bunch in the 80- 90 that looked a bit better than my rear exit sewer that shot in the 2,s and 3,s.
    giphy (4).gif
     

    MTB doc

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    My philosophy on this is
    1. If it shoots I don't give a shit what it looks like inside; I'm keeping it.
    2. If it doesn't shoot I don't give a shit what it looks like inside; it's getting returned
    As you might guess, I don't have a borescope

    ^This Exactly

    Barrels are like tires...
     
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    Frank Green

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    So are you saying this is abnormal and not acceptable work from the smith or are you saying this is typical and not a problem?
    The marks on tops of the lands at the muzzle end....if done during the gunsmithing/crowning the barrel shouldn’t be there. Something really minor and barely visible shouldn’t cause any issues but if it’s really rough/pronounced could cause fouling issues and could lead to accuracy issues. Also take a close look at the crown’s edge. Any burrs there could cause problems as well. Take a Q-tip and run it around the edge. If it’s pulling fibers off most likely a burr. If there is a burr and the first bullet down the bore breaks the burr off it could leave you with a rough edge and again cause accuracy issues.
     
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    Frank Green

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    I would shoot it and see what it does. If it shoots great (put at least 30 to 40 rounds on it) and holds accuracy then don’t sweat it. If it doesn’t shoot then for sure you have a problem.

    I’ll also say....I’ve seen pretty crappy looking barrels/factory and what not shoot great. I tell guys at times....if the gun is shooting great...regardless of how many rounds are on it and it’s holding accuracy...don’t look down the bore!!!

    Sometimes you think you see something (not everyone knows what they are looking at) and as soon as you have a bad shot things start getting blamed that might not be the issue.

    Again to the OP...shoot it and report back! Let’s go from there.
     
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    Frank Green

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    Perhaps ask the smith involved his opinion?
    Agreed....talk to the smith and barrel maker (all parties involved). Sometimes that‘s what should happen first before anything gets posted on any forum.

    I can understand what the OP is asking so he can learn as to what he is seeing/looking at. I understand the wanting to learn part as well.
     

    Im2bent

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    Not to get off topic but those pics look pretty good as far as resolution/clarity too me. What make/model borescope did you use cause now I'm curious too but just for the lulz.
     

    lariat

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    i agree that how it shoots is what matters, and the crown is probably exponentially more important than "defects" or whatever you want to call what we are looking at.
    that said, some barrels look pretty different (although this is hammer forged and not cut).

    View attachment 7572189

    almost 60 year old Model 88 barrel.

    View attachment 7572191
    That’s some sexy work for its day. But why do you got to bring the Germans into it?

     
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    SupressYourself

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    I don't know about the rest of you, but I don't have infinite components to waste on a barrel that looks like that. Obviously something went wrong if the rest of the bore looks good as the OP states.
    What if it shoots .5 - .75? Thats still pretty good, but I would always wonder if it would shoot .2 or .3 without that mess. And I would probably waste even more time and money trying to get it to shoot better.
    What harm is there in running it by the smith and maker? If they both tell him to pound sand, he can still go "see if it shoots" if he wants, and / or take it to another smith and have it chopped and re-crowned. Luckily it's a 26, so you're not losing much by doing that.
     

    theLBC

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    That’s some sexy work for its day. But why do you got to bring the Germans into it?

    hahaha,
    i realize it contributed zero to the question for the op, but each time i post a picture i took it helps a poor like me justify buying the endoscope. :p
     

    demolitionman

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    I’m nearly positive I heard our HMFIC say more than a few times on his podcasts; “stop it with the borescopes people” ....I’m not saying this barrel is ok I’m just saying....
     

    theLBC

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    I agree I wouldn't waste a single primer on that tube.

    Not a single one of my golf bag full of wintac chambered bartlein 5rs have any tool marks left in them when they arrive to me. All perfectly lapped everytime.

    I always check before screwing the barrel on to get a baseline of what the throat looks like new.

    If the op was going to shoot it, I would def show the smith first and clearly let him know I would try to shoot it first but if it didn't group I would be expecting a refund not another barrel.

    If that hurts peoples feelings...tough my business is going to a different smith.
    if i was a smith and somebody brought that back to me, i would probably tell them to fuck off (assuming i wouldn't ship something like that).

     

    Tims

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    From a customers point of view, if you paid for a new top of the line barrel that's what you should get. You are paying your custom barrel maker for a smooth defect free finish with a bore tolerance of .0005 from end to end( or what ever they are lapped to).You are paying your custom gunsmith 500-600 dollars to chamber, thread, cerakote and crown your barrel. Is it too much to ask for a good chamber, thread and crown job? You are paying for custom work. Its not unreasonable to ask for quality machine work.

    Every custom new barrel I've had:
    1. Bore and grove were smooth almost mirror like
    2. Chamber, threading and crowning were clean . What I expected from the professional who did the work.
    3. Shot like I expected them to.

    To the Op: I hope it shoots but I would contact the gunsmith first.
     
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    Huskydriver

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    if i was a smith and somebody brought that back to me, i would probably tell them to fuck off (assuming i wouldn't ship something like that).

    And you know what.... You are totally fine to do that regardless if the barrel looked like that or not....cuz capitalism.... it's great and I like options.

    Just don't be pissed when word of mouth starts hitting back assuming you did ship that barrel as is 🤣 and then told the customer to F off and possibly told him to meet you at the firing line with 5k for a good ole winner takes all shoot off if he doesn't like it cuz you won the palma worlds in 1982. You hang at least 10 sticks a year for your comp rifle and only shoot the ones that "hummer" and that the one you chambered for me will probably outshoot me any day of the week so stfu and deal with it lol 🤣.

    I agree smith should be contacted first before he shoots it, at least let him know so he doesn't pull the old well you didn't break it in properly and your nylon brush you said you cleaned it with, chewed up all this steel and left all these marks. Not my problem.

    I also like the OP don't have 12 barrels being hung every year with enough components to blow in today's market trying to find out which ones will shoot and which won't. If I'm paying 6-800 for a quality barrel and chamber job, I expect it to look like a 6-800 barrel and chamber job.

    It's 2021... Bore scopes are only going to get into more hands as the technology allows it love it or hate it....

    Your customer service as a smith needs to adapt or your business will fail especially as word of mouth travels on social media.

    I'd be interested to hear @LongRifles Inc. opinion for the OP

    LRI has always blown my expectations away as a customer with their CS
     
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    6.5SH

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    hahaha,
    i realize it contributed zero to the question for the op, but each time i post a picture i took it helps a poor like me justify buying the endoscope. :p
    The Teslong are absolutely worth having to see if your cleaning is effective, but do NOT look at a new barrel before you shoot it.
     

    theLBC

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    And you know what.... You are totally fine to do that regardless if the barrel looked like that or not....cuz capitalism.... it's great and I like options.

    Just don't be pissed when word of mouth starts hitting back assuming you did ship that barrel as is 🤣 and then told the customer to F off and possibly told him to meet you at the firing line with 5k for a good ole winner takes all shoot off if he doesn't like it cuz you won the palma worlds in 1982. You hang at least 10 sticks a year for your comp rifle and only shoot the ones that "hummer" and that the one you chambered for me will probably outshoot me any day of the week so stfu and deal with it lol 🤣.
    one reason i'll never be a salesman. just one. :p

    anyway, the important thing is that i find out where this contest is happening and if i can watch it.
     

    CrabsandFootball

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    From a customers point of view, if you paid for a new top of the line barrel that's what you should get. You are paying your custom barrel maker for a smooth defect free finish with a bore tolerance of .0005 from end to end( or what ever they are lapped to).You are paying your custom gunsmith 500-600 dollars to chamber, thread, cerakote and crown your barrel. Is it too much to ask for a good chamber, thread and crown job? You are paying for custom work. Its not unreasonable to ask for quality machine work.

    Every custom new barrel I've had:
    1. Bore and grove were smooth almost mirror like
    2. Chamber, threading and crowning were clean . What I expected from the professional who did the work.
    3. Shot like I expected them to.

    To the Op: I hope it shoots but I would contact the gunsmith first.
    You are paying for a product that performs before one that looks pretty.

    Maybe $500 is alot to you but to the guy paying for the machine, tooling ,building, overhead and labor he doesnt make a ton off of barrel work. Be lucky to make $50 after all is said and done, which isnt shit. He makes money by being efficent not making shit no one ever sees look pretty for the sake of it.

    Some shit is out of your hand. Sometimes shit happens, you take every precuation and still get chatter or a dragged chip. You bid a job based on the plans. A 3" square block built to .0001 will cost magnitudes more than one built to .005, and if you dont need that level of precision for the application, you are wasting time and money.

    I would bet good money the people complaining and talking about tollerences and finish have never cut chips in their life and the people who have actually done this work are saying shoot it before you judge it. They are buzz words they picked up but dont even understand what they mean and the context.

    You have known experts telling you shoot the fucking thing and yet people want to argue and make issues where none may exist.
     

    jakelly

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    Yep, this bore scope went just like every other borescope thread.

    So many "Storm-off's" lol

    View attachment 7572636

    That's NOT true.
    I can't remember the last time I saw a 5g shooting challenge.
    For that matter I can't even remember the last time I saw someone abbreviate thousand with a "g"...

    This thread's been special. OP wanted to learn and I think we've all learned something here.
     

    Tims

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    Nope, not a machinist . Never cut chips in my life. I stated my opinion from a customers point of view.

    I recently received a Bartlein barrel I waited 6 months for. I received what I expected from them. A top of the line rifle barrel. Not only did the interior of the barrel look good the outside was looked like it was highly polished too. Looked "too pretty" to spray cerakote on. I got what I expected from them. A high quality product.

    Years ago I bought a Warner rear sight for a High Power rifle. It was a work of art . Again ,I not a machinist . I don't know what it takes to make a Warner rear sight but Mr Warner made the best. I got what I paid for.A high quality product.

    A prefit barrel for my rifle will be in the 800-900 dollar range. If it cost more for the level of work I expect ,no problem I will pay. Don't expect me to pay top dollar for custom work and then tell me "shit happens". Just because I've "never cut chips" dose not mean I should lower my expectations. You are the machinist. Tell your customers what to expect from your work. Make sure you tell them the "shit happens" part.


    You are paying for a product that performs before one that looks pretty.

    Maybe $500 is alot to you but to the guy paying for the machine, tooling ,building, overhead and labor he doesnt make a ton off of barrel work. Be lucky to make $50 after all is said and done, which isnt shit. He makes money by being efficent not making shit no one ever sees look pretty for the sake of it.

    Some shit is out of your hand. Sometimes shit happens, you take every precuation and still get chatter or a dragged chip. You bid a job based on the plans. A 3" square block built to .0001 will cost magnitudes more than one built to .005, and if you dont need that level of precision for the application, you are wasting time and money.

    I would bet good money the people complaining and talking about tollerences and finish have never cut chips in their life and the people who have actually done this work are saying shoot it before you judge it. They are buzz words they picked up but dont even understand what they mean and the context.

    You have known experts telling you shoot the fucking thing and yet people want to argue and make issues where none may exist.
     

    GrumpyOleFart

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    Are you here for bitching, or shooting.
    I had a Norinco SKS, worst looking bore from new, ever.
    That thing was accurate and has been on sold more times than a crack whore.
    Just shoot the fucken thing, and give us the gossip on how it goes.
     

    jakelly

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    Are you here for bitching, or shooting.
    I had a Norinco SKS, worst looking bore from new, ever.
    That thing was accurate and has been on sold more times than a crack whore.
    Just shoot the fucken thing, and give us the gossip on how it goes.
    Don't beat yourself up. They say English is one of the toughest languages to learn.
     
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    Supersubes

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    I've seen a lot worse looking than that shoot in the ones
    Winchester made a bunch in the 80- 90 that looked a bit better than my rear exit sewer that shot in the 2,s and 3,s.
    Alan, that’s not what I asked. I know that you know how those marks could happen. When a blank arrives to you from a premium maker, and you finish it, are marks like that going to be visible? Were talking about a premium blank, and a smith capable of finishing it, winchester has no place in this conversation imo. Again, the OP is gonna shoot the barrel. We’re talking about the work now. Tell us about the work please.
     
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    Supersubes

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    I'm LOL at this fucking thread

    The blind leading the blind with one exception and that exception's name is Green.
    Many of us that do this work have chimed in and said that it shouldn't look like that, and now Frank has confirmed it. You work in a tech field. The operation for crowning a barrel any number of different ways DOES NOT produce this when done properly, why is this acceptable to you? Serious question.


    Fwiw, I dont think this is a Bartlein, as they’re much cleaner in finish than the OP’s barrel. I could be wrong though due to the OP’s shitty camera.
     

    Near miss

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    Ok,

    Ok, smart ass. You pick the location
    1000 yd kd range
    Prone, sling with iron sights
    The RO holds 5g from each of us
    2 sighters, 20 for record. You game?
    Winner takes,all after tipping the range fees. 45 days notice.
    Let's put the money where mouth is.
    You take OP's barrel to shoot with as you have so much trust in it?
     

    Near miss

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    And also, yeah LL has said many times that you should not borescope, but he particularly means about starting to worry about firecracking, copper and carbon deposits, straches from sand powder, the small rock that got into the chamber and made a hole in it.. All the normal things in the barrel that stand out to folks looking in.

    How about I put my drill in to your barrel and spin it a couple times? Would you have a problem with it? Because that is literally what has happened.

    I own a scope and my barrel throat looks a bit nasty and it is missing a small chunk of crown. Yet it delivers. But you'd have to be some special kind to determine that even because damaged barrels can deliver, damage is a non issue.

    We really need someone to do a barrel torture test, where all kind of crap is done to inside of it and see how the performance changes. A minor problem is that the performance might just become more erratic. But at some point it must be observable.
     
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    reubenski

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    And also, yeah LW has said many times that you should not borescope, but he particularly means about starting to worry about firecracking, copper and carbon deposits, straches from sand powder, the small rock that got into the chamber and made a hole in it.. All the normal things in the barrel that stand out to folks looking in.

    How about I put my drill in to your barrel and spin it a couple times? Would you have a problem with it? Because that is literally what has happened.

    I own a scope and my barrel throat looks a bit nasty and it is missing a small chunk of crown. Yet it delivers. But you'd have to be some special kind to determine that even because damaged barrels can deliver, damage is a non issue.

    We really need someone to do a barrel torture test, where all kind of crap is done to inside of it and see how the performance changes. A minor problem is that the performance might just become more erratic. But at some point it must be observable.
    That has been done. I attended an international sniper seminar in which a fella that was the head of a ballistics crime lab presented some findings from various experiments his team conducted over the years. One experiment was damaging the crown and shooting to determine how much accuracy loss occurred. It took a surprising amount of damage to truly affect accuracy. And in fact the first damage they attempted strangley increased the accuracy. At one point they were going to town on the barrel crown with a drill.
     
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    Near miss

    Gunny Sergeant
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    That has been done. I attended an international sniper seminar in which a fella that was the head of a ballistics crime lab presented some findings from various experiments his team conducted over the years. One experiment was damaging the crown and shooting to determine how much accuracy loss occurred. It took a surprising amount of damage to truly affect accuracy. And in fact the first damage they attempted strangley increased the accuracy. At one point they were going to town on the barrel crown with a drill.
    Yeah, crown can really take a beat.
    One article here, I think is is little bad with that much variance in group size, something other off with that rifle/shooter/ammo combo.


    But if applied the 1% philosophy (even the small gains must be maximized) One can conclude that no particular spot in the barrel makes it accurate. It is the small bits here and there that have been taken care of. Like sharp tools. Good chemicals when cutting, true angles. It all counts up. This is what precision machining is really all about, in my opinion.

    Same applies to shooting.
    -You can feel even the smallest amount of friction change in the cheek pad, put tape on it to increase it so you are happy.
    -Maybe your cheek pad needs still another 0.05" of rise to get the perfect image.
    -Your legs are slightly too offset, fix it.

    (Only) By focusing to the smallest details, can someone get a system polished to the point of near perfection.
     

    CerebralDistortion

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    Oct 8, 2017
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    Let's put the money where mouth is.
    You take OP's barrel to shoot with as you have so much trust in it?
    Oh, come on. That's not what this is about.

    Is the bore pristine? No.
    Does it affect the shooting? Possibly.
    Is it enough to matter? Only OP can tell.

    The barrel maker is not at fault. Presumably.
    The smith is. Probably.

    The main question: Does it shoot?
    (And is OP good enough to notice?)

    On metal, you can see things you cannot feel and that is bl**day annoying (which anyone who has tried to polish metal to a mirror finnish can attest to). As I said before, a digital camera will make flaws really stand out.

    I'll await OP's target pics before judgment...
     

    Near miss

    Gunny Sergeant
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    Oh, come on. That's not what this is about.

    Is the bore pristine? No.
    Does it affect the shooting? Possibly.
    Is it enough to matter? Only OP can tell.

    The barrel maker is not at fault. Presumably.
    The smith is. Probably.

    The main question: Does it shoot?
    (And is OP good enough to notice?)

    On metal, you can see things you cannot feel and that is bl**day annoying (which anyone who has tried to polish metal to a mirror finnish can attest to). As I said before, a digital camera will make flaws really stand out.

    I'll await OP's target pics before judgment...
    Let's make a sharpened example and assume you make barrels and the number 1 in the benchrest world orders one from you.
    Do you let things like that slip, as you assume it won't affect accuracy?
    If you did, you could finish all of your barrels like that. Competitors will start mimicking you and soon nobody wants to buy a "Legacy" barrel without the "Cerebral fingerprint".

    We can ask, what actually makes the difference between a custom and factory barrel.
    Accuracy, for sure. But what about mechanically? Where does that extra cost you pay for goes to?
     

    308pirate

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    I own a scope and my barrel throat looks a bit nasty and it is missing a small chunk of crown. Yet it delivers. But you'd have to be some special kind to determine that even because damaged barrels can deliver, damage is a non issue.
    If the barrel delivers, why is the damage an issue?

    I'm struggling to understand the logic reasoning beyond "because I don't like how it looks"
     

    308pirate

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    Many of us that do this work have chimed in and said that it shouldn't look like that, and now Frank has confirmed it. You work in a tech field. The operation for crowning a barrel any number of different ways DOES NOT produce this when done properly, why is this acceptable to you? Serious question.

    What's the magnification we're looking this through? What is the size (length/height/depth) of these apparent defects?

    How does it do what it was intended to do?

    You know, questions a reasonable machinist or engineer would ask