Category: MTW
Covers MTW-Spec replicas including MTW, MTW-9, MTW-308 and MTW MK18.
Feed Tube and Retention Clip Compatibility/MTW Generations
Depending on the year they were manufactured, MTW receiver sets can be grouped into three generations. Please use this image of upper receivers to determine which generation feed tube your MTW uses and whether or not an engine retention clip is required.
Gen 1
First generation MTWs require the Gen 1 Feed Tube as well as the Engine Retention Clip.
Gen 2
Second-generation Billet Series MTWs as well as earlier Forged Series MTWs, MTW-9s and Article I’s require the one-piece Advanced Feed Tube Assembly.
Gen 3
Third-generation Billet Series MTWs as well as MTW-9s, MTW-308s, Forged Series MTWs and Article Series manufactured after July 2023 require the CNC Feed Tube and Engine Retention Clip.
FRAC Installation
Loosen castle nut with armorer’s wrench. Unscrew castle nut all the way back and slide buffer tube plate back. Don’t lose selector spring and detent if not retained in lower. Unscrew buffer tube.
Install FRAC orientation ring against castle nut.
Install FRAC body with button on the left side of the gun. (Shown upside down. Don’t push the button on the FRAC!)
Thread buffer tube into lower. Align buffer tube to gun and push FRAC up to the back of the lower. Snug down castle nut by hand. Do not thread buffer tube in past the front edge of the buffer tube extension or upper will not install.
Tighten Castle nut with armorer’s wrench.
Remove air line with ¼” wrench.
Install FRAC air line with ¼” wrench.
M4/MTW-9: Use 3.5″ airline.
MTW-308/Shotgun: use 4.5″ airline.
Install engine.
M4/MTW-9: Upside down (airline on top of engine).
MTW-308: Install regularly.
Feed airline through FRAC while holding button, then secure body pins.
308/Shotgun Firmware Configurations
The MTW-308 is shipped with a the standard MTW Spartan Electronics Control Board with dedicated 308/Shotgun firmware. This firmware includes two configurations: “308 Mode” and “Shotgun Mode.” The MTW-308 is set to “308 Mode” from the factory, but it is possible to change the mode accidentally and enter “Shotgun Mode,” which features additional dwell (a longer release of air) only suitable for shotgun builds. You can tell which configuration your MTW is set to by listening to the sound of the dwell. See the examples below.
308 Mode
Shotgun Mode
The configuration can be toggled between the two modes by holding down the trigger for at least 15 seconds. The MTW may fire or make a small click to let you know the mode has been changed.
NOTE: The MTW may also fire after 5 seconds, indicating the select fire mode has been changed. Continue to hold the trigger until the 15-second mark and the gun fires or clicks. If you desired, you can then set your fire mode as desired by holding down the trigger for 5 seconds. See this article for more information: https://www.wolverineairsoft.com/knowledgebase/mtw-spartan-electronics-for-mtw-spec-fire-modes/