Hey guys, I'm hoping yall can help me out.  I have a post ban m4gery upper that is getting way too much gas.  If I try to run with the standard CAR or "H" buffer, I get ftextract.  The extractor will jump right over the rim (yes I've tried the 0-rings, wolff springs, and other extractor aids).  I'm currently running a solid 9mm buffer, and it has cured my jams, for now.  What is the best long term solution to this problem.  The barrel is still very accurate, so I hope I don't have to replace it.  I've seen services where the gas port is plugged and re-bored.  Is this a good idea?  If not, what are my options?  Has anyone else had this problem, and found a cure?

I have seen gas tubes that had a screw in them where you could regulate the amount of gas going back. No idea if they acutally work or not.  

Put a new barrel on it.  They aren't expensive and you can get rid of that ugly post ban barrel.  Check out CMMG's barrels.  I paid $25 to a local gunsmith to replace it for me.

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