I just recently purchased a VR80 12 ga. shotgun. I cleaned the packing oil out and bought 4, 9 round mags. I took it up north and ran it hard. After about 15 boxes of shells. A mix of 7 1/2 low brass and 6 shot high brass it began to fire one round then load but not fire the next. I did a quick field strip and cleaned the gas ring that was very dirty. After that it was running like a champ again. Probably 10 or 12 more boxes of shells and not a problem. Great gun and very fun to shoot. Good luck and God bless.