Choppin down an AR barrel

wmass

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I have an Armalite AR10 a4 and love the gun. Well I love everything but the weight. Im ditching the prs stock and moving to something lighter. My dilemma is the 20" barrel with welded fsc brake. Id like to go carbine length while maintaining the slightly thicker barrel profile. Can the 20" be chopped to 16" and still run reliably with rifle length gas system? I've looked into having the gas port moved but it appears the barrel profile wouldn't allow it.

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I for get where the rifle gas port is on a ar10
Quick fix is drill and tap the hole . Then you tach a set screw so it doesn't move. This is done with old demilled barrels from imported kits . I wouldn't do it on a rifle . Belt fed parts kit you don't care about moa why not. Other option is a dummy sleeve to block if.

Barrel journals can be re profiled.

Personally I would build a different upper . You could buy a barrel . But if you build another upper you know have two for two different uses .
 
Te barrel thins out where the new journal would need to be and its appears pretty damn thin. I do plan on dropping the stock and going with a lighter carbine setup. Im concerned by doing that the rifle will be very front heavy.
i think warwickben has the right idea of setting up a separate upper. Thats what I was leaning towards. Just wanted other pov's
 
Te barrel thins out where the new journal would need to be and its appears pretty damn thin. I do plan on dropping the stock and going with a lighter carbine setup. Im concerned by doing that the rifle will be very front heavy.
i think warwickben has the right idea of setting up a separate upper. Thats what I was leaning towards. Just wanted other pov's

I second the new upper, you're likely going to get into a world of messiness trying to shorten a barrel. You have to worry about a lot of pieces, the smith work alone would probably be more expensive than a new upper.
 
https://armalite.com/shop/ar-10a4-carbine-barrel-assembly/
Been looking for a AR10 possibilities myself. Although the above is out of stock you could just buy a barrel and hand guards. I don't know enough about the AR10s if the buffer tubes and buffers are much different ?

I don't know how much weight you could cut but there's really no reason you can't cut the barrel back to about 1/2" from gas block. Rethread it or just put a target crown on it?
Like a "disapator" style AR
 
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Mac ive been waiting on those for a while. I dont know much about Armalite since the last sale. Rainier has 16" barrel for $300 which I've been considering a lot. The pita is the welded muzzle device would need to be removed to get the hand guard off. Then i have an xtra barrel with potentially jacked up threads. I think building and alternate upper is going to be the way to go.
 
Mac ive been waiting on those for a while. I dont know much about Armalite since the last sale. Rainier has 16" barrel for $300 which I've been considering a lot. The pita is the welded muzzle device would need to be removed to get the hand guard off. Then i have an xtra barely with potentially jacked up threads. I think building and alternate upper is going to be the way to go.

If it's not an expensive Muzzle Device you can simple split it carefully with a cut off wheel or dremel tool.
 
Mac ive been waiting on those for a while. I dont know much about Armalite since the last sale. Rainier has 16" barrel for $300 which I've been considering a lot. The pita is the welded muzzle device would need to be removed to get the hand guard off. Then i have an xtra barely with potentially jacked up threads. I think building and alternate upper is going to be the way to go.

If it's not an expensive Muzzle Device you can simple split it carefully with a cut off wheel or dremel tool. Or carefully remove weld and remove pin.
 
This was discussed at length recently over here:M4 carbine length vs. mid length - educate me


I am pretty sure the caliber doesn't matter, and the principles discussed (the physics of it) remain the same.

This all said, it is probably a wash as far as cost to just purchase a new upper. Then you have two at the end instead of one, so you could always sell one and come out ahead.
 
This was discussed at length recently over here:M4 carbine length vs. mid length - educate me


I am pretty sure the caliber doesn't matter, and the principles discussed (the physics of it) remain the same.

This all said, it is probably a wash as far as cost to just purchase a new upper. Then you have two at the end instead of one, so you could always sell one and come out ahead.

Man is it just me or is it hard to find armalite stuff! Google only comes up with direct armalite listings. Arrgghh.
 
This was discussed at length recently over here:M4 carbine length vs. mid length - educate me


I am pretty sure the caliber doesn't matter, and the principles discussed (the physics of it) remain the same.

This all said, it is probably a wash as far as cost to just purchase a new upper. Then you have two at the end instead of one, so you could always sell one and come out ahead.

Caliber effects all of things. Different pressures involved.
Different gas port hole size and length .
 
Thanks for all the responses guys. I think its best to keep the rifle as is. Its well balanced and damn accurate. I'm layin here in a hospital bed (pancreatitis) bored and letting my mind wander. Gotta learn to leave well enough alone. Maybe if this Matrix arms GB goes off I'll go ahead and build up a carbine. I'd really like to continue with an Armalite pattern since I have prebans for it...but I should be able to live with restricted mags.

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That rifle looks perfect to me. The only thing I would add is a Harris Bi-pod.


I don't have a harris but it normally has a Vltor modpod.
 
Just get a new barrel. It will cost you less than having someone machine it competently.
 
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