Well well... I see I’m not only one who has issues with the RFB. It jams every magazine. I just sent mine back after it LITERALLY fell apart on the charging handle in less than a week. I had to send it back.I'm not happy with my RFB reliability either, seldom get through a mag. Ammo is hard to find these days, even harder to find the same stuff each time. If I knew what tweaks to make I'd get started. Any suggestions besides gas valve?
FF 2 weeks later, I get it back from Kel-Tec as “tested with no malfunctions”. I load in a magazine. First one. Ok. Second mag.. jams on the first round fired. Took it apart and did a quick clean and lube. Put it back together and 3 rounds later the trigger decides to stop working. It’s such a piece of garbage.
I’m sorry for anyone else who bought one.