Hey guys for me it's easy for me to get headshots mid range as heavy but in cqc with smgs and shotguns I feel like I am aiming for the head but its very random tips ?
Purchase a pump-action shotgun and aim for the chest instead, would probably reward you much more for your aim.
Keep in mind that laser sights (and Advanced laser sights) tighten hipfire accuracy, it's not just for cosmetics or even the laser itself. You get the benefit even if the laser is turned off.
Aim such that only the top part of your cone is near the head, allowing the spread and recoil to do the work for you. You don't want to aim directly at the head because that will at least half of your shots to miss entirely. It is better to hit all your shots with most in the chest and a few in the head rather than going all-or-nothing. At least, that works for me when I want headshots.
Aim for the dog-tags (even if they're imaginary dog-tags). This works in most games, at most ranges, I find.