Your Sidearm, Promoted
The SMC-9 is already one of the most capable pistol-format GBBRs on the market. The MCO Zenix Uni takes it a step further — converting it into a fully HPA-powered primary that feeds from standard M4 AEG magazines. It mounts directly to the front Picatinny rail of your SMC-9, and once it's on, the whole platform changes. More capacity, more consistency, and a weight balance that actually works in your favour.
The Zenix Uni feeds from the front, with the magwell positioned forward of the grip. This isn't just a functional choice — it shifts the center of mass toward the middle of the gun, which makes a real difference in how it handles during target transitions and sustained play. The ambidextrous mag latch means you're not fighting the design regardless of which hand you use to reload.
Feeding is handled by the proven MCO single-pin BB retainer system, which keeps rounds moving reliably without dry shots or jams. The magwell shims are built in, so your M4 mag seats firmly with no wobble or rattle — though as with any cross-compatible magwell, it's worth testing your specific magazines before game day. PTS EPM1-S magazines are the recommended choice if you want a guaranteed fit out of the box.
The BB line disconnects without tools when you need to pack down or run maintenance, and the US Foster hose inlet keeps your line routed comfortably out of the way.
Key Features
- M4 AEG Magwell — Front-feed system compatible with standard M4 AEG magazines for increased capacity and faster reloads
- Ambidextrous Mag Latch — Accessible from either side, no awkward reach required
- Tool-Free BB Line Removal — Disconnects in seconds for transport and maintenance
- MCO BB Retainer — Single-pin feeding system for consistent, reliable performance
- Built-In Magshims — Keeps your M4 mag seated tight with no play or rattle
- Forward-Weighted Balance — Optimized weight distribution for improved stability and faster handling
- Modular Platform — Built on the universal MCO Zenix system, adaptable to other models with part swaps
What You'll Need
- Short GTP-9 / SMC-9 magazine (not included — required for installation)
- M4 AEG-style magazines for use during play
- Paintball HPA tank with a low-pressure regulator (0–140 psi)
- US Foster quick disconnect hose (the MCO XF-Lines pair directly)
A Few Things to Know
- Do not exceed 140 psi
- Not all M4 AEG magazines will fit without adjustment — test before game day. PTS EPM1-S magazines are strongly recommended for the best out-of-the-box compatibility
What's in the Box
- Zenix Uni Adapter
- Spare parts bag
- Optional Ultra Light Magazine (available at checkout)
If you've been running the SMC-9 as a sidearm and wondering whether it could do more, the Zenix Uni is a direct answer to that question. It's a clean conversion that turns a capable platform into a genuinely competitive primary — without losing what made the SMC-9 worth picking up in the first place.