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Posted: 3/1/2008 11:34:20 PM EDT
| Getting ready to order one of CMMG's 18" SPR barrels, but am wondering if I should get the mid-length or rifle length gas system. I'm running a rifle buffer setup if that helps any. Will there be any noticeable difference between the two in terms of function and reliability? |
You need to read more carefully. The mid length is smoother than a carbine length because it gets the gas from 2" farther down the barrel so the pressures are lower. The rifle length pulls the gas from 3" farther down the barrel than a mid length which means that the pressures are much lower and it is much, much smoother. In the context of an 18" barrel and which length to use there are two main issues to consider: - The rifle length system on an 18" barrel doesn't leave very much barrel past the gas port. The military uses 18" barrels with rifle length gas systems on their SPR rifles and they have had reliablility issues in very cold (sub zero) weather. Since most of us civilians have enough sense to stay indoors with a cup of hot chocolate on days like that (  ) it should be a non-issue for most people. Also, I think CMMG may be using a slightly larger gas port which would help to reduce this problem.- What handguards and front sight do you want to use? If you want a fixed front sight or you want to use a flip-up front sight that is part of the gas block then you will probably want a rifle length gas system. Longer handguards, longer sight radius, etc. But if you want a low profile gas block that is covered by the a free float handguard then the mid length is the better option. |
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