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How to Assemble an M4 .223

Learn how to assemble an M4 .223 from Police Officer Keith Charley in this Howcast gun video.


Today we're going to talk about how to assemble the M4 Assault Rifle.

As you can see, we have the Assault Rifle disassembled. The first thing you need to do is put the bolt back into the upper receiver. So what you want to do is you have your bolt carrier here and your handle here, you have to make sure this is out. A lot of times what you can do is just give it a good flick like this and make sure it's out that way it properly seeds in the gun.

Before putting the bolt carrier in the gun you have to take the handle and slide it into the upper receiver first. So what you do is, there's a little notch here, you're going to push this in and get that in place just a little bit. Once that's in, you can slide the bolt in. Bring it in and they slide in together. Just like that.

Once they're together, your upper receiver's fully assembled, you need to pair it with the lower receiver.

So you want to do the front first. You're just going to line up the holes and get it in. And then once they're lined up, push the pin back in and now they're together from the front.

As you're putting this together, you want to make sure that the firing mechanism is down. That's the hammer right there. And as you present down, this will go together nice and smooth.

Then just push this pin back in and the gun is back together. You can test it by cocking the gun and firing it. Now you know the gun is reassembled properly.

And that's how to assemble the M4 Assault Rifle.

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