AirTac VFC / APFG M4 / 416 to M4 HPA Magazine Adapter

A VFC gas blowback rifle is a beautiful thing until the gas runs out mid-game, the mag goes cold after a burst, or winter turns a crisp recoil into a wet cough. This adapter replaces the gas magazine entirely, feeding the rifle from an external HPA tank instead, so output stays flat from the first shot of the day to the last regardless of temperature.

It arrives fully assembled. The gas valve, feed lips and gas router are all prefitted, so there is no building, no fettling and no ordering parts you did not know you needed — a genuine difference from the kit-form adapters that expect you to assemble and tune them yourself.

AirTac use a non-VFC high-flow valve rather than the factory part, which is the single biggest reason this adapter handles high FPS and sustained full auto reliably. The M4 base is injection-moulded from an impact-resistant polycarbonate blend, and the gas router is moulded rubber built to standard VFC spec and dimensions, so a factory or aftermarket VFC router will drop straight in if you ever need one.

The magazine catch area is adjustable and ships with three numbered shims that let you tune the nozzle-to-gas-router seal. AirTac test every adapter in a VFC 416 before it leaves them and prefit whichever shim performed best, so in most cases you fit it and play — but if a particular magazine sits loose, swapping the rear shim sorts it.

Compatibility

It fits all VFC M4 variants and the standard 416. It does not fit the VFC 416D — the model with the noticeably flat magazine well — which needs a dedicated 416D adapter instead. If you are unsure which you have, look at the magwell: the 416D is unmistakably flatter than the standard 416.

Specifications

What you also need

The adapter replaces the magazine, not the whole air system. To run it you need an HPA tank, a secondary regulator set within safe pressure, and a US Foster line — none are included. A 68ci tank is the usual choice for a full game day.

Good to know before you buy

It is supplied assembled and tested, so fitting is genuinely straightforward. Note the two things that catch people out: it will not fit a 416D, and it must run through a secondary regulator (see the safety note below). The included spare feed lips are worth keeping in your kit bag — feed lips are the wear part on any HPA adapter.

Frequently asked questions

Will this fit my VFC 416D?
No. The 416D has a much flatter magazine well and needs its own dedicated adapter. This one covers all VFC M4 variants and the standard 416.

Do I need to build it?
No. The gas valve, feed lips and gas router are prefitted, and AirTac test each unit in a VFC 416 before shipping. It works out of the packet.

Which magazines should I use?
AirTac recommend PTS magazines — EPM-LR, EPM1-RX, EPM-1 or EPM1S. Many other brands work too, and if one fits loosely you can swap the rear shim to suit it.

What else do I need to run it?
An HPA tank, a secondary regulator set below 150 PSI, and a US Foster line. None of those are included.

Can I connect it straight to a paintball tank?
No, and this matters. Always run through a secondary regulator such as the AirTac AT200, Wolverine STORM or PolarStar MRS. Never connect directly to a paintball or CO2 tank, and never to a Tippmann-style line.