READ!
It will replace the carbinerifle sound.
with the Battlefield M4A1 sound.
I used this gun for the video :
 https://de.gta5-mods.com/weapons/m4a1-carbine-high-poly 
I recommend to use this gun because it will give you more Battlefield feeling with the sound combined!

MAKE A BACKUP!!

Install :

-start openiv

-go to: GTA V > x64 > audio > sfx > WEAPONS_PLAYER.rpf

-replace mgn_sml_am83_vera.awc

-then go to : GTA V > x64 > audio > sfx > RESIDENT.rpf

-replace weapons.awc

If you use this sound for a mod please credit Sheldon.

Kajot and TheNathanNS helped me to make my first sound mod.Thats why I will mention them in every sound mod that I will upload in future.