I dont think its got 3 rings. its got a metal ring, or combo of rings that remington calls the gas collar and then one o ring near the top of the mag tube. I got a couple of the o rings from the local gun shop but they were kinda pricey so thats why i was wondering how often they need replacing. And i was trying to avoid what happened to you since if im shooting my 1187 at dove im already on my backup (bps is my go to) thanks for the thoughts man.