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dakobster81
06-01-2009, 12:25 AM
ive heard that on a 16" barrel having a carbine gas system can be harsh on the action. is this true? and if so what does that mean? and if you have a 14.5" barrel is a carbine system ok?

Texas Boy
06-01-2009, 12:51 AM
There is some good info on Randal's site - start with http://ar15barrels.com/prod/operation.shtml. Near the bottom there are some graphs that show chamber pressures for different length gas systems and barrels.

Bottom line is the carbine gas system is better suited to a barrel shorter than 16". At 16" a mid length gas system is more appropriate. That said, plenty of carbine 16" systems exist and they do work - but if you have the choice a mid length is smoother, more reliable, and simply better with a 16" barrel.

trinydex
06-01-2009, 7:31 AM
http://www.calguns.net/calgunforum/showthread.php?t=70177

http://www.calguns.net/calgunforum/showthread.php?t=91790

BigBamBoo
06-01-2009, 7:37 AM
..........

fatass
06-01-2009, 9:32 AM
wait, do i need a different buffer if i'm running a carbine? i just got the standard one

dakobster81
06-01-2009, 11:04 AM
so even if you are running say a 14.5" barrel a carbine system is still harsh on the action? would a mid-length still be better on the shorter barrel?

dakobster81
06-01-2009, 11:06 AM
and not only that how much does it really matter being that we aren't using full auto and only shooting it once in a while

Desert_AIP
06-01-2009, 11:09 AM
so even if you are running say a 14.5" barrel a carbine system is still harsh on the action? would a mid-length still be better on the shorter barrel?

There may not be enough barrel forward of the gas port for reliable operation.
Look at a 14.5 " carbine gas, 16" midlength gas and 20" rifle gas.
They all have approximately the same length of barrel forward of the gas port.
This is to give sufficient time for the gas to reach the carrier and operate the action before the bullet leaves the barrel and the pressure dies nearly instantly.

That is why the really short barrel weapons (10"-11") can be troublesome to get to work reliably.

deez
06-01-2009, 11:26 AM
wait, do i need a different buffer if i'm running a carbine? i just got the standard one

You don't need a different buffer, a standard one will work fine.

A heavier buffer can help "soften" recoil though.

GoingPro
06-01-2009, 11:32 AM
im actually looking for site that explains the differences as well for a friend.

trinydex
06-01-2009, 11:35 AM
so even if you are running say a 14.5" barrel a carbine system is still harsh on the action? would a mid-length still be better on the shorter barrel?

ar15barrels said 10.5 might be close to the ideal length for a carbine gas system, but regardless, the pressure is still high when you're tapping gas off the barrel that far upstream.

fatass
06-01-2009, 11:35 AM
You don't need a different buffer, a standard one will work fine.

A heavier buffer can help "soften" recoil though.

gotcha, thanks. being ammo prices as they are i actually haven't shot mine yet.