Bioshot apparently fixed their formulation with their new generation of bbs. You can order straight from their site (I think, if I remember right). You mentioned Bastards jamming in your mags and barrels... that's a little unusual.
Primary: Custom VFC M4 - KJW KC02
Secondary: Custom TM PX4 - KJW Mk1 - KJW M9
Camo: Pencott Greenzone - Pencott Badlands - MARPAT