OzFclass

I wanted to start a different thread from the other one so we all can follow them and keep them separate but don't know how to link the two together other than doing it this way. I wanted to get this started but I'm getting ready to leave work for the day.

The cut off section of the barrel came in from Tony today. On initial inspection I don't know what to say or where to start.

I will say I feel with a 100% certainty the barrel didn't leave here like that but again I will say were all human and things do happen but nothing is adding up from what we see with the cut off piece.

I'll start with the dimensions of the bore and groove sizes. The bore size is beyond the limits of our gauges. Our bore gauge goes up to .2782" and the bore is still bigger than this. If I have to put a close guess on it....the bore is around .2785" maybe even a tad bigger. We bore ream to .2768" to .2769". Then we prelap the barrel. Prelapping we only take out basically a .0001". So that brings us to .2769" to .2770". We rifle the barrel to approx. .2839" to .2840" on the groove size. During the cut rifling process we only cut the grooves. The bore doesn't get touched. So there is no way that during the rifling process it made the bore (tops of the lands) another +.0012" to .0015" bigger.

The bore reamer lets assume is bad and either ropes or reams the bore big. We would've/should've seen it but the bore reamer will not leave the cut/drag marks on the sides of the lands. It would appear something rode up the sides of the lands during rifling. The bore reamer only reams the tops of the lands and this is done before rifling and bore reaming wouldn't be able to leave the marks on the sides of the lands. So it's not from bore reaming.

Also what is odd is the marks on the lands are not just contained to the tops of the lands. The drag marks or if you want to call it cutting type looking marks start on the sides of the lands go over or on tops of the lands and off the opposite sides of the lands. I've never seen that happen with cut rifling. The other thing that would happen if that was the case.....this would lead me to think the cutter was being pulled straight basically as the cut/drag marks don't follow the twist with any uniformity. The cut/drag marks have they're own uniformity it appears. You wouldn't have any twist in the barrel basically which if you look at it there is a twist in the rifling and appears uniform.

These marks should've caused burrs to happen in the bore/sides of the lands etc...if it was a tooling issue and the rifling head/tooling would get jammed in the bore of the barrel during rifling and not only would it wreck the barrel but we would loose the tooling as well. The barrel wouldn't have gotten past rifling at all.

Now to the grooves. The grooves appear to be way to shiny looking. What I'm saying is the finish looks wrong from anything that I see here. It almost looks like it's been chrome plated. Now on to the groove sizes. The groove size is also big. The groove is measuring .2850". That's outside our normal tolerance as well.

I cannot explain how the bore ended up at .2782" or bigger and the grooves at .2850". My first guess is along the lines some sort of bore polishing treatment was done to the barrel.

During the manufacturing of the barrel the bore gets measured and visually inspected after reaming. After the barrel gets prelapped it will get measured and visually inspected again. Then it goes into rifling and the barrel gets measured for size towards the end of the rifling process and before it gets pulled from the rifling machine. Once the barrel is to the size it needs to be the barrel at that time is pulled from the machine and besides the size it is visually inspected again. Then the barrel gets finished lapped and again is visually inspected. Between the different times it gets measured and visually inspected if it happened here something somewhere should've been caught. The marks are so bad you can see them with the naked eye. Again with the bore not being to size and the grooves not being to size and the drag marks and the finish being off in the grooves nothing is making any sense to me.

I will bring my camera in tomorrow and see if I can take some different pictures and will post them.

I will also email Tony privately as I have more questions for him but will email him tomorrow morning our time.

I will stand behind what I said and that we will replace the barrel if he cut off a chunk of his and sent it to us and he did. So I will get a order cut for him for a replacement tomorrow as well.

Right now though I'm drawing a blank as to what is going on/happened to the barrel. Will work on it some more.

Later, Frank
Bartlein Barrels

Frank - I have a piece of the barrel here too. I noticed the same bore dimensions but only go to thou once I get above my pilots so assumed 0.2780-2790 but doesn't seem consistent (ie worn more in some places).

A note picked up by a very astute gunsmith here was the
gouges "seem" to start running with the rifling at bottom of slope on lands then when they get to the top they track across and directionally down bore (diagonally across rifling), then track down the other side and start heading with the rifling again. I don't know if this is an optical illusion with the canted lands but maybe worth looking at - and a very interesting coffee table discussion-- - It can be seen in Tony's video on the other link

It has us all stumped but for Tony's sake (and others) I hope we find the issue before another one goes down flusher.

A stainless tumbling media pin??

A disgruntled employee?

BATattack wrote:A stainless tumbling media pin??

I think the directional change ruled this out for me (magic bullet syndrome) - providing it isn't just an optical illusion???? - should just punch straight through the lands.

DaveMc wrote:

BATattack wrote:A stainless tumbling media pin??

I think the directional change ruled this out for me (magic bullet syndrome) - providing it isn't just an optical illusion???? - should just punch straight through the lands.

Yeah it's very interesting particularly since Tony seems pretty diligent in his processes. I don't know how a stainless pin would go down a barrel but in my mind it may start to try and follow the rifling and cause strange markings.

I haven't seen the barrel in the flesh like you guys have so it's just a theory.

Shifted my broken leg post and "thank you" over to its own off topc thread, so as not to side track this very important Bartlein perspective

Jees Tony lucky you were wearing your helmet
I bet you will be itching to get back on the range once you have mended.

All the best and warm Regards

RICHARD

BATattack wrote:

DaveMc wrote:

BATattack wrote:A stainless tumbling media pin??

I think the directional change ruled this out for me (magic bullet syndrome) - providing it isn't just an optical illusion???? - should just punch straight through the lands.

Yeah it's very interesting particularly since Tony seems pretty diligent in his processes. I don't know how a stainless pin would go down a barrel but in my mind it may start to try and follow the rifling and cause strange markings.

I haven't seen the barrel in the flesh like you guys have so it's just a theory.

This is a good thought. A very good gunsmith over here and has worked on my rifles (lives about 8 hours a way from me) just had to replace a barrel for one of his customers and he had left the stainless tumbling media in the cases and the rounds got loaded and fired down the barrel. I'll give Moon (gunsmiths nickname) a call and see if he still has the barrel and if he does have him send it up to me so I can look at it.

Later, Frank

Tim N wrote:A disgruntled employee?

LOL! That's a good one but all the same guys are still here! If he was disgruntled it must have been just for a few days or so!

Later, Frank

Tried to take a couple of pictures. Sorry not the best!

First picture is of a new 7mm barrel and has not been installed on a rifle/shot etc...



Your looking right at the top of the land with the angle on both side of the lands and a little bit of the groove on each side.

Next picture is of one of the lands in Tony's barrel.



Notice how the drag/gouges come up the sides of the land, onto the top of the land and not seen in this picture they go right off/down the other side of the land.

The next picture is of one of the grooves in Tony's barrel. The gouges stop right at the sides of the lands and don't touch any spot in the grooves anywhere.



This is what is puzzling me. Lets say it was a chip hung up on the cutting tool or rifling head then the gouge should be taken into the grooves and there is nothing. This picture doesn't show it good and I could not get a picture with out glare from the new barrel etc....but the finish in the groove in the above picture seems smoother/more polished almost like it's been chrome plated. It just looks different than what I normally see.

Besides things like stainless tumbling media.....the other thoughts that come up are....

Was the barrel fire lapped?

Some type of paste cleaner used and it wasn't gotten completely out of the barrel? Then the first rounds fired the bullet forces the grit of the paste into the bore but you would think it would damage the grooves as well?

Paste cleaner used with a brush etc...? The brush wasn't rotating with the rifling and skipping over the lands along with the compound? I've seen this before but the scratches/gouges didn't look anything like this (this deep/bad) but it the scratches were confined to the tops of the lands. I didn't really notice any on the sides of the lands. This was in a 6.5x284 F-Class rifle barrel. We tried to save the barrel for the customer as he brought his rifle to the shop but no matter what we did we couldn't save the barrel/get it to shoot/not foul anymore. We had 3-4 customers in one year that wrecked 4-5 barrels. One guy wrecked two of two of them. I know the gunsmith that did the work and bore scopes all of the barrels he does before and afterwards and he confirmed that the shooter wrecked them with using a paste cleaner. The only common thing amongst these shooters/barrels was they all used a paste cleaner. Did they leave some paste in the bore and fired rounds down the barrel? Didn't clean it all out?

Was any type of electro bore polishing done to the bore of the barrel? Black Star use to electro polish the bores of rifle barrels but are no longer in business.

Later for now!

Frank

Were the bullets tumbled/polished before loading and the fired down the barrel?

Might sound funny but I've talked to the guys in the past who were tumbling/polishing the bullets before loading them. As well as tumbling/polishing loaded ammo.

If so these could leave a film/cleaning media on the bullets, cases etc...and when the ammo is fired in the gun this media will go down the barrel as well.

Where nickel plated cases used in loading the ammo and fired in the gun? I'm going to say no but I have to throw it out there. If I remember correctly this is a .284win. and I don't know of anybody making .284 cases with nickel plating.

I won't use nickel plated cases for loading my ammo. Why? The nickel plating is very hard and can and will flake off. If and when the nickel gets into the chamber and bore and the rounds are then fired the nickel/metal particles can scratch the bore of the barrel as well.

Later, Frank

What if he had JB Borepaste or similar stuck in the grooves of the rifling ? when you fired the .284 projectlie it would gather up the paste like a wave infront of it at 50000 psi and shove it down the barrel ? just an idea

A few random thought:
As I said yesterday in the post that I shifted :
Mark Fairbairn did comment that I am the only one he has seen who uses KG2 (the bore polish) on a bronze brush.......rather than on a patch or cloth wrapped around a nylon brush. As I pointed out to Mark, the instructions on the side of the KG2 bottle specifically says to use it on a bronze brush, so I am literally following the manufacturers instructions !
It is filthy dirty bloody stuff but I have always shaken it really well, and in most cases 10-15 strokes, gently up and back, is normally enough to remove all visible copper provided KG1 has been used first as per instructions, to get rid of carbon and powder fouling
I use copious amounts of Shellite to rinse out after using KG2 or JB's Bore Paste.3 or 4 saturated wet patches, then 3 or 4 dry patches, and commonly repeat that 3 or 4 times. Always finish with a dry patch wrapped around a sft nylon brush.....and do that 2 or 3 repeats.
Always oil with Ballistol even if using the next day. Oil is dry patched out, then I use the Shooters Choice" process of 2 x wet patches to ensure the oil is cleaned away, then wo dry patches. That leaves the desired light coating of Shooters Choice as a bore conditioner for the first shot.

Have never used Nickel cases. Only Lapua and Norma.

I do use stainless tumbling pins, but only started with that at approx 700 round mark, and this gouging had definitely started before that.
When using the stainless pins, I really do take extreme care to get them out.
I am the one who lost a Broughton 6mm barrel due to ReddingApplication Media remember ! It was all shared on this forum with a lot of photos.
I multiple rinse the Thumler tumbler, flushing the water over the tilted edge multiple times.
Then one handful at a time I transfer the cases over to a 3 liter clear plastic beaker, making sure each case is drained of the pins as they leave the Thumler Tumbler . Overflow rinse again.
Then get 3 or 4 cases at a time, make sure they are all aligned the same way, then invert them ensuring each case is totally filled and underwater......then drain them by tipping them upside down and shaking into the clear beaker
Then dry them by putting on a nail board with 4" nails. It's a piece of 8" x 1" thick maple. I then run my fingers backwards and forwards, up and down the rows to spin the cases multiple times and multiple direction changes on top of the 4" nail. That probably sounds pedantic, but I do it specifically to ensure that there are NO PINS left in each case.
With my pedantic system of draining and drying, there has never been a single pin on the maple nail board......ever.....and there has only ever been two pins in th bottom of the 3 liter clear plastic beaker that I "final rinse" in. It seems that if you take great care as they leave the Tumbler, filling and inverting each case, that the pins do slide out of the case very easily.

I have never tumbled/polished either bullets or loaded rounds.

As a neck lube for the cases that have tumbled I use either Lockease (applied with a Q tip to the inside of the neck) or the Forster white mica set up with the three brushes in the red plastic case. Choice depends on the mood that I am in. The Lockease needs to be well dried so that powder doesn't hang up and the Forster mica set up is a messy, fiddly bloody thing.
The original tub of Redding Application Media ceramic balls still sits on my bench as a constant reminder of how easy it is to blow $1000
Tony