Just an after-thought, but if I were going to replace gas rings on an AR that apparently wore the first set rather quickly..... I would make sure that I installed high quality rings, to help rule out the rings if this re-occurs.

I would also suggest that you carefully check your old rings (preferably under magnification) to see if there were any rough or flat spots on the rings. I would also carefully examine the "carrier bore" to look for rough spots.

Once the rings are installed, don't forget to do a repeat "ring test" to see a baseline. If it fails the test with new rings, then I would suspect that the bore of the carrier is slightly oversize.

I apologize for any errors in terminology. I kind of make them up as I go ....( sign of an amateur!! )

PS: Cool video find by Powermad!