Cut and thread 12.5" AAC barrel to 9"?

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jessmcquaid
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Cut and thread 12.5" AAC barrel to 9"?

Post by jessmcquaid »

Does anyone know if there is enough barrel profile diameter to cut down an AAC 12.5" barrel to around 9-9.5" and have proper threading/shoulder? The barrel profile seems to taper and then flare back out at the muzzle.

picture borrowed from AAC's website

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Nic56
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Re: Cut and thread 12.5" AAC barrel to 9"?

Post by Nic56 »

I have no idea as to answering your question. But, if it were my barrel, I would just buy a 9" and sell the 12.5". It just seems like an easier solution than sending it off to be cut down, wondering if it would cycle properly and hoping it was threaded concentric to the bore. Of course, a reputable business should do it properly. But, I would also assume any warranty on the barrel would be void after shortening it.
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A-Game
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Re: Cut and thread 12.5" AAC barrel to 9"?

Post by A-Game »

Cost involved is more of a factor. A concentric thread is easy. Think about this though, if you can't find a 9" AAC barrel Noveske would be happy to sell you one for the same price.
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dellet
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Re: Cut and thread 12.5" AAC barrel to 9"?

Post by dellet »

Depends on what you are planning to mount.

Many suppressors want a shoulder of at least .750, which is the diameter of the journal for the gas block. The barrel will be less than that from there forward.

If it is not a direct thread you might have more options, but you will need to talk to the manufacturer of your chosen mount.
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Re: Cut and thread 12.5" AAC barrel to 9"?

Post by TMD »

Not sure what locals charge by you to cut and thread a barrel but around me they all want $100 or more. I'd say your better off buying a new barrel and selling your old one.
jessmcquaid
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Re: Cut and thread 12.5" AAC barrel to 9"?

Post by jessmcquaid »

Hi all, thank for the feedback. I got an offer to buy the upper at a really good price but it seems not worth the trouble. I ended up going a different route.
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300Blk
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Re: Cut and thread 12.5" AAC barrel to 9"?

Post by 300Blk »

I wouldn't. Too much trouble and cost, and you would have to use non-standard threads.
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Re: Cut and thread 12.5" AAC barrel to 9"?

Post by A-Game »

If the diameter is smaller then you might be stuck with a 14mm thread or 15mm thread like a fal uses. Yes I know it isn't a metric thread but it is 15mm diameter.
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