Cracks in the flutes of my barrel?

alanmc

Hi all,

I was cleaning my barrel today and noticed some scratch marks in the flutes of my barrel. On closer inspection, they seem to be cracks. Mostly at the chamber end, and in some of the flutes, they seem to extend further down the barrel.

It's a .308 Win barrel off my Unique Alpine TPG-1 (factory barrel). Accuracy is still dead on. But I'm worried about these "cracks" now.

I'm guessing I should have this looked at. Has anybody seen stuff like this before? Is it a common failure on fluted barrels?

Any insight or advice is appreciated,
Alan.

gunny123

Cracks normally start at sharp edges and corners, not in smooth rounded surfaces like that.
I would contact the importer/ manufacturer, and of course i would not dare firing it until the issue was resolved.

alanmc

gunny123 wrote: »

... and of course i would not dare firing it until the issue was resolved.

100% agreed.

gunny123

You might be able to take the barrel to somewhere that does non-destructive testing of engineering components.

Metlabs ireland have places in dublin and cork. They could xray or ultrasound test the barrel for you.

Cass

They're not cracks, they appear to be gouges. I would hazard a guess it was a "Monday morning" or "Friday evening" barrel.

To be on the safe side, as the lads said, i'd have it inspected by a gunsmith (a competent one), but don't fire until you have it checked.

I've seen some pretty awful fluting over the years. From a chap that "tried his hand at it" and left a sharp on one side and rounded on the other side fluting to a lad that took out so much material i'd say the barrel was thinner than tissue paper. in the bottom of the fluting

That would seem to me to a rough reamer (has a burr or chip) or piss poor CNC machine tool/operator. Depending on how Alpine do it. If you're only noticing them now then asking if you seen them before is pointless, but i'd imagine they were always there and you're only noticing them now. However, and i have to say it again, i'd have it checked before firing as it's your face on the firearm. Better off taking no chances.

If it's gouges then it's only cosmetic and won't effect the firearm. If it's cracking them it's time for a new barrel .

May Contain Small Parts

Nothing to do with shooting, I just wanted to pop on here to thank OP for the laugh I got when I read the title on the front page.

august12

May Contain Small Parts wrote:

Nothing to do with shooting, I just wanted to pop on here to thank OP for the laugh I got when I read the title on the front page.

I second that, had to check in to see what they were referring to,

Kat1170

May Contain Small Parts wrote: »

Nothing to do with shooting, I just wanted to pop on here to thank OP for the laugh I got when I read the title on the front page.

august12 wrote: »

I second that, had to check in to see what they were referring to,

Could be worse, could be cracks in the barrel of his flute :o:(

alanmc

Cass wrote: »

They're not cracks, they appear to be gouges. I would hazard a guess it was a "Monday morning" or "Friday evening" barrel.

To be on the safe side, as the lads said, i'd have it inspected by a gunsmith (a competent one), but don't fire until you have it checked.

I've seen some pretty awful fluting over the years. From a chap that "tried his hand at it" and left a sharp on one side and rounded on the other side fluting to a lad that took out so much material i'd say the barrel was thinner than tissue paper. in the bottom of the fluting

That would seem to me to a rough reamer (has a burr or chip) or piss poor CNC machine tool/operator. Depending on how Alpine do it. If you're only noticing them now then asking if you seen them before is pointless, but i'd imagine they were always there and you're only noticing them now. However, and i have to say it again, i'd have it checked before firing as it's your face on the firearm. Better off taking no chances.

If it's gouges then it's only cosmetic and won't effect the firearm. If it's cracking them it's time for a new barrel .

Thanks as always Cass. So you reckon it's probably just tooling marks from manufacture?

I'm definitely going to get it checked out. As you said, it's my face.

alanmc

May Contain Small Parts wrote: »

Nothing to do with shooting, I just wanted to pop on here to thank OP for the laugh I got when I read the title on the front page.

Ha. Never even crossed my mind when I was writing it.

Cass

May Contain Small Parts wrote: »

Nothing to do with shooting, I just wanted to pop on here to thank OP for the laugh I got when I read the title on the front page.

Kat1170 wrote: »

Could be worse, could be cracks in the barrel of his flute :o:(

Heh, now thats all i can read i as.

Cass

alanmc wrote: »

Thanks as always Cass. So you reckon it's probably just tooling marks from manufacture?

The pictures are of good quality and you can see the "valley" of the scrap mark. Its not "dark" which indicates a crack (see through the material). You can see material under/in the gouge which, to me, indicates a gouge and nothing more.

I'm definitely going to get it checked out. As you said, it's my face.

Do for that very reason. "Cass said it was fine" will be of no comfort to either of us, especially you, if i'm wrong.

solarwinds

Good chance they could be stress fractures considering they are at the chamber end only for now. This would be the highest temp and press initially and the valley of the flute would be the thinest point. You can get hairline fractures in steel that are not evident until put under pressure.
To me if it was caused during the milling of flutes on manufacture the gouges would be linear the length of the barrel.
But either way something you are not confident with you will not trust. It definately needs further investigation before firing again.

Cass

solarwinds wrote: »

To me if it was caused during the milling of flutes on manufacture the gouges would be linear the length of the barrel.

I'm not an expert, i'm not even familiar with metallurgy to be classed as competent. However while they are not perfectly linear they are "with the grain".

The other thing that makes me think they're gouges is the marks as the machining tool goes into the fluting. I've marked them here to highlight them.

But either way something you are not confident with you will not trust. It definately needs further investigation before firing again.

Absolutely.

solarwinds

Yep i agree the last 2 pictures do look like gouges but the first 2 im not sure about.

Grizzly 45

What you could also do for a quick opinion, is ring the Birmingham proof house in the UK and ask to speak to one of the proof masters,tell them your story and send them the pics to look at. They will have seen every sort of barrel and any and all states before they went to catastrophic failure and be able to tell you possibly whether this is a potential bomb or not.

Also, if it is an EU manufactured gun,it will have to have by law proof marks from the country it was made in[IE France in this case?].So they might be able to tell you if this has been seen before around Europe as they get technical bulletins that don't really make it into the public domain.

ejg

10-30 mag microscope will tell a lot already and would be my first port of call. Then non destructive florescent penetration liquid. Found a few cracks in a friends Ruger bolt with that method. I couldn't tell from those pictures.
edi

alanmc

Sent some of the photos to Dom Byrne. He can't be sure without physical inspection, but thinks they look like cracks. I'm going to bring it down to him next weekend.

A new barrel may well be in my immediate future.

Thanks for all the help lads.

meathstevie

Roughly how many rounds through it and factory loads or "hot" loads ? If it's not an exorbitant amount of standard factory ammo after going through it and they're cracks you may well be looking at a barrel that wasn't fit for purpose.

As Grizzly said, get in touch with the likes of Birmingham, Ulm and in this case if the gun is French the St-Etienne proof house. If it has happened before they will have had it documented at some stage.

alanmc

meathstevie wrote: »

Roughly how many rounds through it and factory loads or "hot" loads ? If it's not an exorbitant amount of standard factory ammo after going through it and they're cracks you may well be looking at a barrel that wasn't fit for purpose.

So, Ive only had the rifle for the last year and put about 300 factory rounds through.

It's a 10 year old rifle though, so I don't know the full history. For all I know it could have been firing hot hand loads for years. Accuracy is still amazing though.

alanmc

So I'm just back from my first visit to Dom's. Absolutely sound bloke.

My barrel definitely has cracks in it. Dom bore-scoped it and saw some debris from a cleaning patch exactly where one of the worst cracks is. Possibly hung up on the crack inside the barrel!!!

Either way, I'm retiring it. "Accident waiting to happen" is what Dom said.

Cass

alanmc wrote: »

My barrel definitely has cracks in it.

Well balls, no pun intended.

Either way, I'm retiring it. "Accident waiting to happen" is what Dom said.

Absolutely. You done the right thing by not firing it when it was only a suspicion, but now it's confirmed it's bin time.

Only good thing is, depending on the severity, some parts of the barrel might be salvageable and reworked for a muzzle break, invisible thread cap, etc. Only a thought.

alanmc

Cass wrote: »

Well balls, no pun intended.

Ha.

Cass wrote: »

Absolutely. You done the right thing by not firing it when it was only a suspicion, but now it's confirmed it's bin time.

Only good thing is, depending on the severity, some parts of the barrel might be salvageable and reworked for a muzzle break, invisible thread cap, etc. Only a thought.

A fellow boardsie came to my rescue and sold me an almost new Alpine barrel he wasn't using.

I'm thinking of havimg my old one rebarreled in 6.5 Creedmoor so I can fully use the switch barrel capabilities.

Grizzly 45

alanmc wrote: »

Ha.



A fellow boardsie came to my rescue and sold me an almost new Alpine barrel he wasn't using.

I'm thinking of havimg my old one rebarreled in 6.5 Creedmoor so I can fully use the switch barrel capabilities.

Cost you almost as much as just buying a new 6.5 Creed barrel. Do you really want to shoot somthing that already has material failure ? As Cass said, make useful bits out of it

alanmc

Grizzly 45 wrote: »

Cost you almost as much as just buying a new 6.5 Creed barrel. Do you really want to shoot somthing that already has material failure ? As Cass said, make useful bits out of it

No no. The cracked barrel is scrap. But the adapter it screws into is just fine. The adapter is what slots into the switch barrel system on the Alpine. So I'm planning on getting a new 6.5 CM barrel and fitting it into the adapter.

The bolt locks into this adapter through the action meaning your headspace is always right. It's a pretty neat system.

solarwinds

The cracks are the visible damage you can see. Better to use it as suggested for parts, of a non load bearing kind. I definately not use it as a barrel again.

alanmc

The dark grey bit is the adapter. The barrel is just screwed in to this. A new 6.5 CM barrel screwed into tgis adapter will be using none of the damaged material.

Cass

Why not?

If you want a 6.5cm (with the complimentary man bun ) then go for it.

alanmc

Cass wrote: »

Why not?

If you want a 6.5cm (with the complimentary man bun ) then go for it.

Ouch!

What other caliber would you go for if you had the opportunity?

Bear in mind, I'm not on the reloading scheme, or else I'd probably have gone for the 6.5x47. I have yet to see a RFD with x47s.

philmire

Good job you got it checked out I work with metal every day and was deffently not machine marks from your pictures shown could of had a hand grenade if you kept shooting it

Cass

alanmc wrote: »

What other caliber would you go for if you had the opportunity?
.

Just taking the piss. :P

The 6.5cm is producing some impressive results. I've always loved the 6.5 caliber with the old 6.5x55 being my favorite. However ammo choices were getting slim with the ever increasing popularity of the 308, but the 6.5cm seems to be doing the business. As a short action rifle with the superior ballistics of the 6.5 bullet it is better than the 308 and ammo seems to be readily available.

There is nothing else in short action i think i would consider when looking from a factory ammo point of view.