KMRDragon

I've fired 8 rounds through the R1 and almost didn't get the barrel removed from the piston because it was soundly stuck. I can see carbon fouling inside the piston chamber. Is brake fluid the best to remove it? I can tell you regular bore cleaner won't touch it. I can see the retaining ring on the piston, but I'm unclear how to remove it? Also I'm using federal 180 power shock. Is there anyone who has used a different amo with less piston and chamber problems? Thanks!