Rifle-length gas system do I need to change anything?

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Rifle-length gas system do I need to change anything?

I have an AR-15 with a mid-length gas system and I'm going to be changing out the barrel to a rifle-length match. Anything need to changed in the buffer system, etc.? It has a Colt H1 buffer and Colt buffer spring now. Will it work as is or am I overlooking something?

Thank you very much!

[markm]

h2 would most closely match a rifle buffer system. H1 might work ok. This all depends on the barrel and the port size of course.

[Rascally]

I have a 20" rifle length .223 Wylde with a carbine stock, standard spring, H1 buffer. No issues, 223 lands about 3:30, 5.56 lands about 2:30.
As markm said, depends on barrel and port size, but I don't expect you would have any issues. While the dwell time is about an inch longer, the gas pressure at the port is lower.

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The barrel is a Lilja 20" .223 Wylde, 0.093" gas port hole, rifle length gas system. http://riflebarrels.com/shop/drop-in...23-8-ar740-20/

At this point I'll install the barrel and see how it cycles. Thanks for your help...

ar740_2018-03-06.jpg

[Bob Sacamano]

Recent data point.

BCM chrome lined, 20" barrel, rifle gas (0.093" port), standard BCG, Sprinco green spring. Cycles PMC bronze through IMI 77 and 55gr fine. Even assembled a few heavy A2 buffers and at 7.1 oz, still cycles everything.

Going to try an LMT E-carrier and adding a buffer weight spring from an A5 buffer. If building another one, would start with a BRT GB with a 0.089" port and A2/A5-H2.

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Turns out not changing anything worked perfect for changing a mid-length barrel to a rifle-length gas system. Same everything just a barrel change!