MK23 Covert M4 Mag Adapter

Versions for other Pistols, semi/bolt rifles as well as left handed versions are currently in testing so will also be available soon, including;

  • AAP
  • Hi-Capa
  • Glock
  • SRS
  • VSR-10
  • KC-02

With other mags potentially available on request, just message me here and I can see if the system would be suitable. Follow me on Instagram for the latest products as they are released. 

Looking for the ultimate sidearm? I was too. For me, the MK23 came so close; sound, range, accuracy... 

But my main gripe was the consistency of green gas. The solution? HPA…  

No drop in FPS between the first and last shot, therefore consistency; useable regardless of temperature; huge capacity for hundreds or thousands of shots between tank refills; and adjustable FPS so you can always be at your field limit.   

But this introduced the issue of BB capacity. Having to change the line to a new mag with each mag change every 30 shots; that’s not for me. 

I couldn’t find a solution that I liked, as I'm not partial to huge mags/adapters sticking out of the bottom of pistols making them look like some sort of tactical boomerang.  

So I designed my own.

This is a covert M4 mag adapter which mounts horizontally to the lower front rail of TM and clone MK23s, giving the lowest profile possible. This then feeds BBs directly into the pistol mag via a flexible metal spring tube, using the power of the spring in the M4 mag.  

The mag is HPA tapped with a high quality US foster fitting (Airsoft and Paintball industry standard), allowing you to connect your existing HPA tank and regulator. 

The system has been in design and testing for several months, with many game-days-worth of testing to make sure that it is reliable, consistent and durable.

Feeding
One of the main concerns for most people will be feeding. The device has been tested primarily using the PTS EPM1-S (170 round) mags. Feeding has been optimised at every part of the BBs travel, from the m4 mag to the hop rubber, meaning that as much resistance has been removed as possible, and you aren’t going to be dry firing when it matters most.

As this was my main concern too, this has been focused on during testing. After many design iterations and numerous test days, by myself and my select few beta testers, it has been performing brilliantly, reliably feeding the entire EPM mag.  

Noise
By using mid-cap mags there is absolutely no BB rattle. The adapter has been designed to hold the mags firmly in place, so there is no tapping or clicking when the gun is in use or holstered. Different nozzles and retention arms are included to ensure a perfect fit for any mags you use.

Reduced Mag loss 
The mag catch and release has been specifically designed to reduce the risk of dropping mags, as I know from bitter experience that there's nothing more sad than dropping a mag on the field. Fortunately, there is a highly recessed yet ergonomic release catch, meaning mag drops are much less likely, but reloads are still easy and fast.  

BB Retention
As there is a large feed path between the M4 mag and the feed lips, there are approximately 50 BBs which will remain in the system once the mag is removed. To stop these from coming out between reloads, there is a BB retention arm built into the M4 part of the adapter, meaning that only 1-2 BBs are lost when removing the mag, regardless of the angle you are holding the pistol. 

Other Mag Compatibility
The adapter has been primarily tested with PTS EPM1s, however it will work with any (all currently tested) M4 mag you already own. Not only that, but it can be optimised for any mags using the alternate mag kit, which includes multiple nozzles, retention arms and mag release catches, so that you can have the same firm fit and BB retention as with the default config.

Please bear in mind that EPMs have been chosen for their feed strength as well as capacity. You may find that other brands ]have less tension force pushing the BBs, so these may struggle to feed reliably.

Maintenance and Replacement Parts
When designing the adapter, maintenance was a huge focus. The adapter itself has a detachable tube, meaning that it can be taken apart for cleaning, or to replace parts should they need it. The nozzle and retention arm can also be taken out and replaced on the rare occasion they are damaged.

Durability
Great care has gone into the design and print orientation of each part, to ensure maximum strength to the most vulnerable part of each component. So although 3D printed, the adapter is very sturdy, with the adapter itself is easily able to withstand a full body weight without any damage. As such, day to day wear and tear should only cause aesthetic damage the adapter.

Holster Compatibility
The adapter has been designed as to not interfere with the popular trigger guard retention-based holster (you know the one) and allows for the exact same draw as when using the stock magazines. (When using a right handed version. A left handed version of the adapter is currently in testing and should be available soon).

QC and Support
As these are currently being manufactured by myself, each unit is tested in-house to ensure the highest level of quality control. If you experience any issues with the system then I will provide as much support as you need, including replacement parts. Any feedback you can provide will also be greatly appreciated!

Batches will be released in small quantities as they are made, so if currently out of stock, units will be available shortly.