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Barrel Query

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Can I ask the members here to provide the measurements to determine which gas length system is on a 308AR barrel.  Looking at possibly replacing my barrel to ensure a bit looser headspace than "match"....I prefer function over having that kind of accuracy differential between a match chamber and a standard/7.62 type chamber.

And as an aside....:lmao: I have been told that the bolt is what makes the headspace on the AR.  Please confirm what I have been told.  This would make a bolt change more what I am looking for.

1/2 case deep with some Rebel Rouser IPA.....sorry if my thoughts and ideas don't come across correctly.

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Q1. What is the barrel length ?

Generally a 16" or shorter will take a carbine length gas system. 

A 18" barrel could use carbine,mid or rifle length.

A 20" or longer barrel can use a rifle length gas system.

The shorter the gas system the harder the bolt carrier slams in its cycle.

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I had always understood the bolt,extension, and chamber together create the headspace.

I have a 16 inch barrel with a rifle length gas system, runs nice and smooth so there are no hard and fast rules there.

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 Why not have your chamber Finish Reamed to a 7.62x 51 chamber, no change in Head space , just a slightly different chamber dimensions . You should still check it with the proper Head space Gages.

 Or polish the Chamber , it may be tight because of it being rough .

Edited by survivalshop

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Thanks for the info guys. 


I will look into finding a smith around here to get some pricing on a finish ream. 

And mine is a 16" barrel with the rifle length gas system also.

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