Gunsmithing distance from gas port to muzzle

Rhys

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I've got a DPMS LAR-308 That I'm thinking about cutting the barrel down on. Anybody know right off hand just how much barrel needs to bee left ahead of the gas port?
 

cruizer

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Re: distance from gas port to muzzle

Ive cut one to 18" and it runs great. It seemed overgassed at 24" though
 

skinnj1

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Re: distance from gas port to muzzle

Is it a carbine lenght gas system or a Rifle length?
 

AXEMAN

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Re: distance from gas port to muzzle

lar-308 is a stock 24", so rifle. but as cruizer said, several suggested i just cut it to 18" rather than source an 18" with carbine specs.

OP, you can get an 16"-18" kreiger from fulton and sell that one
 

skinnj1

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Re: distance from gas port to muzzle

AXEMAN- I was trying to verify what he had before I answered his question. DPMS does not make a L<span style="font-weight: bold">A</span>R-308, they do make a LR-308 and LR-308 AP4 is the correct designation for a carbine (http://www.dpmsinc.com/store/products/?prod=4854&cat=1940). There are a lot of "large frame" AR's out there and I wanted to make sure I understood what he had before I gave my opinion. If it is a rifle length system I agree 18-18.5" is as short as you want to go.
 

Rhys

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Re: distance from gas port to muzzle

That was my typo. rifle length AR in 308. I was pretty sure there wouldn't be a problem going down to 18 inches or so, but didn't want to find out the hard way that I had cut it too short.
 

cruizer

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Re: distance from gas port to muzzle

if you want it to be handy, turn it down also. I cut one to .650 in front of the gas block and .750 under the gas block nd handgaurd