Borescope evidence of the death of a very good barrel

[AlanF]

Tony,

That external photo showing the evenly repeating pattern of the "vines" suggests to me that its a bore machining problem that happened before the rifling was cut, and not a steel quality problem. I also think it would have been there since the barrel was new, and must have been much harder to see through the "sheen" of the new bore surface. This would mean the depth of the vine pattern is very shallow, and looks worse than it actually is.

As a possible fix, I like your idea of shooting it without cleaning for a hundred or so rounds and see if accuracy improves. A few of the top shooters didn't clean for the whole of the Townsville Queens, so its not a radical strategy!

I hope it comes good - and my order with Craig for another Bartlein definitely still stands !

Alan

[plumbs7]

Hi Tony , that's why you've struggled ! I new u were a lot better shot than what u have been getting.
I've heard of some tr shooters getting 12 -13 000 rounds out of their .308 and they haven't gone near it with a cleaning rod . A shooter at Cannon Hill RC was doing this , thought he would get a new barrel just in case . He cut the old one in half and said he could still see tool marks in the rifling!

Cam posted just before somewhere that he got 4000 rounds out of his 284 .

The amount damage u have with such low mileage is concerning .....I wander if super cleaning may have contributed ???!
We won't know !
Kind regards Graham .

[DaveMc]

I think you should certainly take it straight to Bartlein. If they had an issue with any machining it will show up in more than just the 2 barrels that Tony Berry owns and am sure they will replace them. They also probably see more "issues" or barrel claims than any of us - they have probably seen anything that can happen.

1) On machining. Bartlein are single point cut rifle barrels. The final machining and lapping is all done in direction of rifling. These 'gouges" are certainly not following the rifling and appear to be more parallel with bore. I don't know the Bartlien process but normally before cutting the rifling the centre is drilled and reamed and sometimes honed. None of these machining processes would follow the direction of these gouges. Pre lapping of the bore (before cutting) would be in the correct direction but these are deep gouges for lapping compound (possibly a machine rod if machine lapped) but I seriously doubt Bartlein would do that anyway .

2) Do the gouges continue all the way down barrel? Are they heavier at the muzzle or throat or consistent for the length?

Dave

[ecomeat]

You've said that the dodgy section is the lands. It may be that I'm not looking at it properly, but the dodgy part looks to me like its the grooves. I stand to be corrected, but in my experience, the grooves are normally narrower than the lands.

Denis,
this is the second Bartlein barrel muzzle


i will also post the straight link, and hopefully if you click on THAT, it will open some Photo viewer on your computer , that lets you blow it right up for a closer look
http://s862.photobucket.com/user/ecomea ... e.jpg.html

Similarly with the "problem" barrel. Open this link in a seperate programme on your PC and blow it right up as far as you can
http://s862.photobucket.com/user/ecomea ... e.jpg.html

One last one of the problem child, taken last night. Where the clear land disappears against the crown, in the photo, the ugly bit is very evident

The ugly bit actually goes all the way to the crown edge, but its not in focus in the photo, and so it appears flat

Here is its seperate link so you can blow it right up
http://s862.photobucket.com/user/ecomea ... t.jpg.html

Finally the second Maddco

[jasmay]

Tony, I am with Dave, I would be passing all this info on to bartlein, the worst that could happen is they say nothing.

DennisA, It's pretty easy to see the lands just by holding your barrel (out of action) up to a light looking from the chamber end.

[ecomeat]

Tony, I am with Dave, I would be passing all this info on to bartlein, the worst that could happen is they say nothing.

Yes, have just done that.
Got an automated response back saying "Due to the amount of emails we receive and the amount of phone calls we currently are not staffed to handle the volume we are receiving. Please be patient and will respond to you as best we can.
Thanks, Bartlein Barrels"

Hoping to hear back from them sometime this week !

[ecomeat]

2) Do the gouges continue all the way down barrel? Are they heavier at the muzzle or throat or consistent for the length?

Dave

Dave,
Just went and measured it carefully. From the chamber :
Just 1/8th of an inch from the base of the ramp at the beginning of the lands, its visible on the sides of the Land
At about 3/4 of an inch further, it starts on top as well.
At a further 1 and 7/8 inches (2 and 3/4 inches from the very start of the "ramp") it is all over the top of the land. ie the land is fully damaged within 2.75" of the very start of the Lands.
Tony

[Malcolm Hill]

Tony
It appears to me to be a problem with the barrel steel being too soft. If it was anything to do with the boring , machining or lapping of the original hole before rifling then the problem would not be evident down the sides of the lands. This area as well as the bottom surface of the grooves should have the finish left by the cutter during the rifling process. Depending on groove diameter vs projectile diameter the force exerted by the projectile on the groove surface varies but from what I have evidenced it is usually not that great. Reasoning of that is due to where you generally get light to moderate carbon build up starting in the corner of the grooves and working its way across to the middle of the grooves . If there was a lot of pressure and the projectile was forced hard down into the grooves I don't think you would see this happen. Same reason you don't get much copper build up in the bottom of the grooves, the pressure and friction between projectile and barrel doesn't seem to be high in this area. Copper build up is usually always on the top of the lands in a conventional square cut barrel where the forces are highest but in a 5R type barrel with angled lands it does tend to creep down the sides a bit as well. What I am saying is that your problem is only occurring in the area's subject to high friction loadings, hence my reasoning that it may be due to the steel being a bit on the soft side.
Regards Malcolm.

[AlanF]

Maybe it is the steel Malcolm, but mine was bought at the same time, so must have been from a completely different batch because mine is not only the most accurate barrel I've had, but possibly the least prone to throat erosion. I lined up 5 barrels (including Bartlein, Kreiger, TF and Maddco) side by side on a table and scoped them all for the full length of the bore. The US made barrels definitely had the least throat erosion (for their age), and the Bartlein scored best.

Alan

[IanP]

Tony, excellent info and photos and I have never seen a barrel look like the one you have on show. I like others wonder if the barrel stock the steel has come from is to blame?

Thanks for letting us all know just how bad things can get with "quality" barrels. Any chance of the manufacturer giving you a replacement? If I had manufactured this barrel I would not want the pictures on the internet doing the rounds and at the very least give the customer another barrel or two.

Ian

[DaveMc]

For the record I don't think it is a manufacturing issue. (Could be but evidence is not that strong - sorry Tony but I need to say it and I am sure you will forgive me eventually) Please everyone be careful of blaming manufacturers until all investigations are carried out. I do however believe the manufacturer will be the best help here. They will let Tony know if there indeed has been any other issues and replace his barrels for sure if there was. If not then you need to look closer to home.

1) Only two barrels so far found with this issue. Both with the same owner. Until more are found there is a stronger correlation with owner than manufacturer (2/4 barrels compared to 2 out of thousands). If Tony had only 1 then I would suggest it could just be a Dud but 2/2 from that time whilst other owners have no issues is a bit strong. It could be but we need to find more before jumping to conclusions. Perhaps if all those with borescopes and Bartlein barrels can take a look. I have looked down a couple up here in the recent past and seen nothing like that. I have also just asked a couple of people I met in the states that use Bartleins and they have never heard of this issue either.
2) The direction of the grooves tells me it is not a soft steel issue. If it was soft steel "peeling" or other then it would be in the direction of the rifling. This is not. It also does not appear to be stress fractures but true "gouges". Fire or stress cracking or peeling would be parallel or at 90 degrees to rifling. This gouging is more in direction of barrel, not rifling. It is working at odds to projectile and cleaning brush and patch direction.

So it appears to be something travelling fairly straight down the barrel. If it was done in manufacturing then I would have thought it would be noticed earlier than now and probably in their QA checks. Also Firing and cleaning projectiles would be smoothing rather than enhancing the gouges in this case.

It is so unique though that I don't like guessing but would look closely at all processes that go straight down the barrel not with rifling (manufacturing, cleaning and firing etc). Brads joking suggestion of garnet in the powder sounds crazy but actually makes some sense???????? or those stupid ball bearings used for lubricating necks that find there way into the powder. The gouges look consistent (machine like) in one photo but quite random in others.

Sorry Tony but I see a great deal of frustration ahead for you. If one still shoots well then bench the worst and fire the better one and closely watch what is happening as you proceed.

I feel for you.

VERY VERY PERPLEXING!?????

[ecomeat]

Thanks for all of the input.
This is definitely NOT a Bartlein "bashing" exercise.
I have put it online on this forum for the sole purpose of sharing the photos and information, and asking for opinions from our F Class "family".
We are, after all, quite small in a global numbers sense, so its important to me to get feedback from as many experienced Aussie F Class shooters as possible.
Bartlein are undoubtedly a world class barrel maker whose product is literally famous.
I remember looking at an Equipment List from a major USA Benchrest title a couple of years ago, and something like 18 or 19 out of the Top Twenty in Light Gun were all Bartleins.
I will share the Bartlein response on here when i get it.
Tony Berry

[DenisA]

Hi Tony,

Great pics and vids, thanks for sharing.

You've said that the dodgy section is the lands. It may be that I'm not looking at it properly, but the dodgy part looks to me like its the grooves. I stand to be corrected, but in my experience, the grooves are normally narrower than the lands.

I just want to correct my previous comment as I was wrong. I checked a few of my barrels, different brands, and the grooves were all wider than the lands. ............. sorry Tony for the dumb comment

Certainly a bit of an optical illusion.

[IanP]

Thanks for all of the input.
This is definitely NOT a Bartlein "bashing" exercise.
I have put it online on this forum for the sole purpose of sharing the photos and information, and asking for opinions from our F Class "family".
We are, after all, quite small in a global numbers sense, so its important to me to get feedback from as many experienced Aussie F Class shooters as possible.
Bartlein are undoubtedly a world class barrel maker whose product is literally famous.
I remember looking at an Equipment List from a major USA Benchrest title a couple of years ago, and something like 18 or 19 out of the Top Twenty in Light Gun were all Bartleins.
I will share the Bartlein response on here when i get it.
Tony Berry

Tony, I dont think anyone reading this thread will think its a manufacturer bashing exercise. A very small percentage of all manufactured goods whether made for aerospace or sport can be defective and find their way thru quality assurance checks and into circulation.

Its a very interesting thread and its a very specific problem that needs the expert opinion of a barrel maker. If Bartlein are busy and cannot respond anytime soon maybe a second opinion would be a good idea. Do you think it would be possible to discuss what may have caused this barrel's condition with the Aussie manufacturer Maddco?

Barrel manufacture explained here: http://www.firearmsid.com/feature%20art ... acture.htm

Ian

[Norm]

Tony,

Are you sure with the canted lands that the rod is actually turning with the rifling at the same twist rate as the rifling, rather than slipping or partially slipping over the lands as you push in the rod.
The part of the rod where the jag screws onto the rod is made of steel and could be marking the lands.
Just a thought.