M4 Mag Adapter: MP5 or X9 Mag Option?

Question:

I want to run an HPA adapter in my gas shotgun but prefer feeding from MP5 or X9 magazines instead of M4 mags. Does Primary Airsoft offer a version compatible with those magazine types?

Answer:

Yes. The KC02/KJW HPA adapter listed at https://primaryairsoft.us/ is available in three distinct magazine-well configurations: M4, MP5, and X9. You select the version matching your preferred magazine platform at checkout. This adapter fits the KC02 and KJW gas shotguns, converting them to HPA while accepting standard AEG magazines for the chosen platform.

The MP5 version accepts common MP5-style AEG midcaps and high-caps. The X9 version is designed for the Action Army X9 / T11 magazine pattern. Both function identically to the M4 variant — they replace the factory gas magazine, bolt into the magwell, and connect to your HPA line via a standard quick-disconnect fitting.

Internally, the adapter uses a durable feed tube and reinforced magazine release catch to handle the cycling forces of a gas shotgun action. Spare parts — including feed tubes, O-rings, magazine releases, and screws — are sold separately on the site if you ever need to refresh a high-round-count build.

If you already own an M4 adapter but want to switch platforms, you cannot simply swap the magwell; the magazine interface is integral to the adapter body. You would need to purchase the MP5 or X9 version outright.

Pair the adapter with a regulated HPA rig (regulator, line, tank) and quality 0.28 g–0.32 g BBs for consistent CQB performance. Always verify your field’s FPS and joule limits with the intended BB weight before playing.

Running an HPA or mag-fed setup?

Primary Airsoft makes HPA adapters for Hi-Capa, Glock/AAP-01, MK23/SSX23, SSQ22, 1911, Beretta M9, CZ P09, CZ SP-01, KWA KMP9, KWA MP7, SMC9/GTP9 and more — feeding M4, MP5 or X9 magazines — plus magwells, green gas nozzles and adapter spares. Shop them at primaryairsoft.us.