Cracked Feed Ramp

[Duman]

Have a cracked feed ramp. Anyone know of a smith that can replace the sleeve?
5809458095

[SideShow Bob]

Give Bert at BP Tactical a call. His contact information is down in the Industry Partners section.

[Great-Kazoo]

Fairly simple replacement of the bbl extension. Call Bert, he's about 35 min south of you.

[USMC88-93]

Has Bert started taking in work again post surgery?

[BPTactical]

Has Bert started taking in work again post surgery?

On a limited basis, I just went back to work last week on very modified duty. I am still locked down to a 5# weight limit on my left. Getting stronger everyday but I have to be super cautious of over exerting it.


OP- I have never seen a barrel extension crack like that.
A couple of things to consider:
The barrel extension has a tremendous impact on headspace. Unless the new extension is an identical match to the old one we have issues.
The threads must clock exactly the same or the locating pin will be out of time resulting in a canted front sight/gasblock.
Is your barrel chrome lined? If so then there is no prayer of adjusting the headspace with a reamer if need be.
I would be really curious to take a look at the bolt. To me damage like that could be a big hint of severe over pressure. Usually bolt lugs will batter or shear but I suppose an extension could crack.

Per the TM's IIRC if there is any damage to the extension the barrel is to be replaced.
If we have to do a bunch of work to time a new extension and deal with headspace issues you will very quickly approach the cost of a new barrel.

[68Charger]

Theoretically (just as an exercise), IF you mill the extension until it was timed to match... then the headspace would be off... given the variables of where the extension threads start, the torque required, etc... I 100% agree with Bert- It could likely take several hours to get it right, and possibly dozens of extensions to find one that is timed close enough to mill (need one that is very close, within tolerance of headspace)

I've actually looked at discount barrels (like $40 when it was hard to find any barrels available) that did not include extensions- but after research, the hassle of finding an extension to match made it no bargain, even if free.
The problem lies in that when the barrels are manufactured, the gas port and any other timed marks on the barrel are not done until the extension is attached at the proper torque and headspace... because there is no "timing" at that point... then they drill the gas port based on the timing of the feed ramps.
You'd actually be better off putting a new extension on at the correct headspace, weld up the old gas hole & drill a new one. Depending on if the gas block is drilled & pinned.

All that exercise aside, I also agree something went seriously wrong for the extension to crack like that- I'd personally throw away the bolt unless you're willing to have it inspected (MPI or other crack detection method).. maybe the extension was was defective from the start... but how could you know?

One question- Who made the barrel?

[thvigil11]

One question- Who made the barrel?

My thoughts exactly. Would be interesting to diagnose to figure out what went wrong. But unless we are talking a super high end barrel, it might not be worth the time and money to replace the extension. Good barrels can be had right now in the 2-300 dollar range, shooter barrels are anywhere from 90-200. What are the potential costs of a smith to replace the extension, while making sure the timing and headspace are correct. Plus there is the unknown of if there is that kinda damage to the extension, what is the condition of the barrel? I'd say MP'ing the barrel would be a good idea.

[ray1970]

I'm going to have to agree with everyone else. Not worth the time and money to fix. I'd just get a new barrel.

[ray1970]

Oh, and assuming the bolt looks good and you weren't having an issue with bad ammo, I'd venture to guess that the barrel extension wasn't properly heat treated. Would kind of make me question the barrel as a whole anyways.

[hurley842002]

. Would kind of make me question the barrel as a whole anyways.

And at that point, I can't help but question the whole rifle...

[thvigil11]

And at that point, I can't help but question the whole rifle...

I'd question everything in the safe, no telling how one bad apple can affect the whole bunch.

[ray1970]

I'd question everything in the safe, no telling how one bad apple can affect the whole bunch.
Why stop there? I'd look pretty hard at the house and vehicles as well. Could be something contagious going around on the home front.

[68Charger]

And at that point, I can't help but question the whole rifle...

sounds like BRD to me...[Coffee]

but in all reality, all the pressure in the AR platform is between the bolt, extension and barrel.

[Duman]

ROTFLMAO !! [LOL]

Can't go anywhere else with a smithing question, and leave with advice on your vehicles and shelter! LOL!

The barrel is a Sabre Defence, stainless, and is in excellent condition. The....er...'conditions' under which this occurred shall remain limited to a small group of individuals. Suffice it to say there was no loss of life or limb.

Rifle had been back to Sabre for repair, got a clean bill of health, then i discovered this. (Note: Sabre is no longer in bidness...something to do with importing gun stuff without telling the G-men)

But the warm thoughts are appreciated.

So...I think the barrel weighs <5-lbs., so when can I drop it off? [pick-me]

[BPTactical]

No, Sabre's demise was FA items ending up unaccounted for....like out the backdoor and employees pockets.


Realistically Duman I feel investing in a known good barrel and bolt would be a prudent move.
Not that I would mind making the money but let's make sure you spend your cash in most beneficial way to you.

[Great-Kazoo]

No, Sabre's demise was FA items ending up unaccounted for....like out the backdoor and employees pockets.


.

How True. Seems they started where CAVARMS left off.

[Duman]

No, Sabre's demise was FA items ending up unaccounted for....like out the backdoor and employees pockets.


Realistically Duman I feel investing in a known good barrel and bolt would be a prudent move.
Not that I would mind making the money but let's make sure you spend your cash in most beneficial way to you.

My new Wilson Combat upper arrived this afternoon, going to install TBA brake on it this week.

Before pulling the barrel, and finding ramp cracks, the barrel shot green tips all day long but jammed with FMJs. Visually comparing the Sabre and Wilson ramps, Wilson is smoother and the FMJs seem to feed smoothly.

Just hate to waste a good barrel.

[68Charger]

Just hate to waste a good barrel.

I can understand that, but consider the possibility that it's NOT a good barrel anymore...

I pulled some tires out of storage, and found the spare had a tread separation explosion....
Literally had belts poking out the hole... I thought what a waste, then decided that was better than it blowing while I was driving on it.

[Duman]

Well, since the barrel is now a tomato stake, I'm interested to learn how the feed ramp extension comes off. There is a retaining pin, of course, but that's in there pretty good. Suggestions?

[Great-Kazoo]

Well, since the barrel is now a tomato stake, I'm interested to learn how the feed ramp extension comes off. There is a retaining pin, of course, but that's in there pretty good. Suggestions?

Pull the pin, use correct tool OR old Bolt to remove. Plan B if you don't care about the extension a good pipe wrench. Chances are it will come of fairly easy. NOW if you have no use for the bbl i'll be happy to take it for a SBR 22 project