Ever wonder how the United State Army’s M4 carbines stand up to the harsh environments around the world and still function properly? From the desert dust of Iraq, to the mountain mud of Afghanistan, soldiers must keep their weapons in pristine shape. Having a clean and well maintained rifle may be the difference between life and death for these soldiers. But how do they keep them maintained while they are out in the field? I will be explaining the basic process of disassembling and assembling an M4 Carbine, which is commonly known as a “Field-Stripping”.
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Step 1: Safety Check
The very first step to the disassembling process is the most important; make sure the weapon does not have a bullet in the chamber. To do this, hold the weapon with the barrel pointing in a safe direction. This will most likely be pointing down at the ground. Once it is pointed in a safe direction, grasp the charging handle at the rear of the rifle (it will resemble the letter “T”), and pull it to the rear. Still holding the charging handle to the rear, press in the bolt catch. The bolt catch is on the left side of the rifle; it is oblong and will pivot when pressure is added. While applying pressure to the bolt catch, slowly let the charging handle travel forward. Allowing the charging handle to slide forward, let go of the bolt watch. This will cause the internal bolt carrier group to stay to the rear of rifle, which will expose the Star Chamber. Next, tilt the entire rifle to the left so that the Star Chamber is visible. The Star Chamber is at the base of the barrel and shaped like a star. Visually inspect the Star Chamber to insure that there is not a bullet chambered. After visually inspecting it, take a finger and put it in the Star Chamber to physically insure that it is clear of obstructions. Lastly, press the bolt catch to send the bolt forward. Upon completion of the safety check, the rifle is ready for the disassembling process to begin.
Step 2: Separating the Upper and Lower Receiver
The disassembling process begins by pressing in both take-down pins. The take-down pins are located above the grip and where the magazine well meets the rifle. After pressing both of these out, the rifle will split into two parts: the upper receiver, which is what the barrel is attached to, and the lower receiver, which the grip is attached to.
Step 3: Taking Out the Internals
Set the lower receiver aside. While holding the upper receiver, grasp the charging handle and pull it to the rear. After doing this, the rear of the bolt carrier group will be exposed. Grip the exposed area and pull it back at a downwards angle. This will cause the entire bolt carrier group to come out the upper receiver. Set the bolt carrier group aside. While the charging handle still to the rear, press down on the top to pop it out. After this step, the upper receiver is now fully stripped. The next step is to disassemble the bolt carrier group.
Step 4: Bolt Carrier Group Disassembly
To begin the disassembly process on the bolt carrier group, lay it on a flat surface with the bolt facing outwards. The bolt is the section that is in the shape of a star. On the left hand side of the bolt, there is a firing pin retaining pin (it is the only one on the right side). Remove this pin. Once this pin is removed, the firing pin will be able to be taken out.
Step 5: Firing Pin Removal
The firing pin is a bright silver rod that runs through the entire bolt carrier group. Flip the bolt upwards and lightly tap on a solid surface, which will release the firing pin.
Step 6: Cam Pin Removal
The next step is to separate the bolt from the bolt carrier. To do this, the cam pin must come out. The cam pin is the rectangular pin located on the top of the bolt carrier. Twist the cam pin 90 degrees, and then pull it out.
Step 7: Separating the Bolt and Bolt Carrier
Lastly, the bolt and bolt carrier can be separated. That is the final step to Field-Stripping an M4 Carbine.
Step 8: Conclusion
To reassemble the rifle, do the steps in reverse order. It may sound complicated and time consuming to do this process, but it becomes second nature after doing it a few times. It is beyond crucial to recognize the procedure in the correct steps of the process. Field-Stripping is used to clean and diagnose malfunctions in the weapon. The disassembling and assembling process can be done in a very timely manner, which makes the M4 Carbine so effective in various environments. Once the process is learned, maintaining the weapon is fairly easy to keep up with. This is one of the main reasons why it is chosen as one of the main weapons used by American soldiers during battle. As always, weapon safety is the responsibility of every soldier; thus, this procedure must be implemented properly in order to have the reliability that this weapon has been known for.