Gas system length discussion

[draco41]

I have been thinking about this for awhile now and decided to ask for the groups input. I purchased a Kotonics 6.8spc upper awhile back, but before doing so, wanted to read up about the 6.8 round. In doing so I came across several articles about the proper length gas system for the 6.8spc and the use of carbine length systems. In short, the thought that the carbine length is too short for the 6.8s added powder volume and the use of intermediate or longer gas systems is recommended to avoid excessive gas pressure inside the gas system. My question is this, Is the gas system on the 16" and 18" LR-308 a carbine length or intermediate? Not having my LR-308 yet, (still acquiring parts) I don't know what the actual length is.

[imschur]

16" are carbine. 18" has both carbine and mid-length options. DPMS

[draco41]

That's interesting, the carbine length does cause excess pressure in the system? seems like the 308 would cause a lot more gas then the 6.8?

[imschur]

The carbine length gas system is tougher on the weapon then rifle length for sure. The reason for custom buffers and springs regardless of caliber

Sorry I dont know anything about the 6.8, maybe others members do.

[C7Prod]

Not sure if what Ive read is accurate but it seems that the barrel manufacturer drills the gas port the optimum size for the cartridge/Barrel length configuration. However if you are still concerned, use the JP adjustable gas block and adjust as per the instructions and your problems should be resolved. Hope this helps.

  C7Prod