The JB M4 CQB Airsoft-brand rifle is a non-lethal replica of a military grade weapon. The “stubby” design of the barrel makes it more suitable for close-quarters “combat” than a standard rifle, but the less-than-ergonomically designed fore-grip handle at the back causes accuracy to suffer because of improper handling. You can upgrade the JG M4 by replacing the handle with a more ergonomically designed model. Replacement handles are available from hobby shops and select gun stores that sell airsoft-brand replica weapons, and the partial disassembly of the JG M4 does not require any special tools.
1. Remove the magazine clip from the JG M4 CQB airsoft-brand rifle — the clip is inside a compartment just in front of the trigger guard on the underside of the rifle.
2. Remove the screws from the side of the battery grip handle that is at the rear of the rifle using the Phillips screwdriver. Remove the faceplate from the handle and place it aside. Remove the battery pack from inside the handle; first pull the battery clip off the battery with your hands. Place the battery pack aside.
3. Grip the fore-grip handle that is in front of the battery grip handle by its bottom. Hold the handle steady as you push down on the pin at its top where it meets the chassis of the gun using the tip of a flat-edged screwdriver. Alternately you can grip the edge of the pin with a needle-nose pliers.
4. Twist the fore-grip handle from side to side to dislodge it from the chassis. Pull the handle off and place it aside.
5. Place the top of the ergonomic replacement fore-grip handle up against the chassis from where the original handle was just removed. Twist the replacement fore-grip handle so as to engage its clips to the underside of the chassis. Pull up on the pin to lock the handle to the chassis using the tip of the screwdriver or the needle-nose pliers.
6. Return the battery pack to its original position in the JG M4. Place the faceplate back on and reattach the screws. Return the magazine clip to its original position in the underside of the rifle.