How to Make M4 CQBR Out of M4 (Airsoft)

One day I went airsofting with my AK-74U(Because my MK.18 Mod 1was too big). And on my way home I thought, since there is no M4 CQBR, why don't I make one by myself. So I went to market, bought myself a Colt M4 and start making it. 
Anyway here is what u need for making M4 CQBR
1-Airsoft Colt M4
1-Duct Tape
1-Office Knife
1-Lighter
1-Super Glue
1-Saw
1or 2-Rail
1-Sand Paper

Step 1: Measure the Length of Barrel.

Before u get into sawing and gluing measure the length of the barrel. Since there is inner barrel I measured it with pencil.

Step 2: Mark It! 1

If u r done with that mark the place where u are gonna saw.

Step 3: Saw It! 1

If u r done with that Saw it.....

Step 4: Voila! 1

After u r done with sawing it should look like this.

Step 5: Mark It! 2

Now pick up the barrel that u sawed off and mark the place where u will cut(because u need flash hider).

Step 6: Saw It! 2

Now saw it....

Step 7: Voila! 2

The flash hider should look like this after u sawed it off.

Step 8: Sand Paper! 1

Now with sand paper soften the sawed part of flash hider and the gun.

Step 9: Attach It!

Now attach the flash hider to your gun with super glue and duct tape.

Step 10: Finished!

Now your M4 CQBR is finished. Now go out and get 'em Private!