AR15 thread cleaning

[StacattoP]

So I bought an upper from a member here he was very clear and very open about the condition of the threads he sent me plenty of pictures so I knew exactly what I was getting into I just wanted to get that out of the way. I tried contacting Allison Carey to clean up my threads but they said it would be about 5 weeks before they can do a simple job. The barrel was pinned and welded and then removed and it looks like there's a little bit of slag just blocking the flash hider from coming down that needs to be removed I was wondering if there was anybody in the area with the appropriate tool to do so I can compensate them or if anybody knows what tool I need to accomplish this. I'm only posting the photos so folks can see what I'm talking about but to be clear again I was aware of the condition when I bought it and the member was very open about it

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[cigars]

Hope you didn't spend too much on that, but a bargain's a bargain. You can try cutting the threads again. It's going to be rough when you hit that glob of weld so you may have to dremel that down first. If you're lucky, you can still continue the thread over that. Start with a thread chaser. 1/2" 28tpi. Brownells sells the die.

Drill America 1/2 in.-28 Carbon Steel Hex Re-Threading Die DWTSH1/2-28 - The Home Depot

Drill America Hex Dies are for rethreading over brusied or rusty threads. They are the most cost effective type of rethreading tool available. No special holder is required for this type of die.

www.homedepot.com

 

[StacattoP]

Hope you didn't spend too much on that, but a bargain's a bargain. You can try cutting the threads again. It's going to be rough when you hit that glob of weld so you may have to dremel that down first. If you're lucky, you can still continue the thread over that. Start with a thread chaser. 1/2" 28tpi. Brownells sells the die.

Drill America 1/2 in.-28 Carbon Steel Hex Re-Threading Die DWTSH1/2-28 - The Home Depot

Drill America Hex Dies are for rethreading over brusied or rusty threads. They are the most cost effective type of rethreading tool available. No special holder is required for this type of die.

www.homedepot.com

New barrel?

 

[TTSX]

I've rethreaded worse than that. A good die, plenty of lube and a little patience will get you through just fine

 

[jbett98]

I've chased bunged up threads using the correct sized grade 8 nut that I cut in half with a thin cutoff wheel and then clamped it just tight enough with vise grips to back it out towards the damaged area, working very slowly and with lots of thread cutting oil.
Don't use anything but thread cutting oil, as that has lots of sulfur in it and it's a necessary ingredient.
I use this method when the starting threads are messed up, usually on wheel studs

 

[Pepe-lepew]

Just grind off the buggered threads. There is more than enough good threads left to secure a flash hider.

 

[Member 34319]

Looks like they straight up removed the muzzle device without grinding away the welded pin.

A 1/2x28 thread die should be about all that is needed to get it functioning.

I'd be curious if the inner bore diameter changed at all due to whatever the hell they did. If that pin in the circled area of your picture? Then they likely didn't do due justice to remove it correctly. If that's true, the pin has to move metal to get out of the way somehow. IE forcing metal inward.

 

[DirectDrive]

If that's the remnants of the pin, I'd try to get it off of there first before running the die.
Use oil, cutting oil if you have it.
Back the die out as resistance increases and then take another small bite...rinse and repeat.

 

[Rkangel]

Looks like they straight up removed the muzzle device without grinding away the welded pin.

A 1/2x28 thread die should be about all that is needed to get it functioning.

I'd be curious if the inner bore diameter changed at all due to whatever the hell they did. If that pin in the circled area of your picture? Then they likely didn't do due justice to remove it correctly. If that's true, the pin has to move metal to get out of the way somehow. IE forcing metal inward.

View attachment 1161412

I would also be concerned about the receiver side of the barrel. If they didn't use a barrel vise while removing the muzzle device, that potentially put a lot of torque into the receiver and index pin.

 

[DirectDrive]

I would also be concerned about the receiver side of the barrel. If they didn't use a barrel vise while removing the muzzle device, that potentially put a lot of torque into the receiver and index pin.

Very good point.
Bubba doesn't use barrel clamps, so hopefully it wasn't him.
Also wondering if the muzzle is jacked from all that torque.

 

[edzz]

Triangular needle file time. Just clean the threads up, don't over think it.