The hit detection is completely **** broken and random. Many times landing a clean hit on a stationary enemy with my DSG1 will not register at all. Other times that same enemy will 2 hit kill me with a scar from 100m away, and no headshots.
Melee seems to be a game of gambling dice. You either kill or be killed at full health in 2 hits, or it SOMEHOW takes you 5 direct hits to do any damage.
Getting the jump on someone means nothing half the time as the game frequently will throw away half your shots as the enemy simply turns around and kills you in less than a second... in armor mode.
Everyone uses the Scar because its the only weapon in the game with a good enough RoF and very little recoil to make it so the hit detection isn't as bad. Even if the game wastes 10 bullets with it's terrible detection you still make a kill 100m away in less than 2 seconds.
However this makes sniping a game of gambling since often your shots never register. Slower RoF weapons like the kvolt and MG are useless because of this.
I've never in my life played a multiplayer game with such inconsistant and broken hit detection. It would be one thing if it was always bad all the time for everyone - but it's not. Sometimes you (and only you) will land hits where you actually fire. Other times your bullets go into thin air. Ping seems to have no effect too, I go in the lowest player and ping servers, the game says I have "50" ping in game and yet half my shots do nothing at all against someone who somehow always manages to hit from a great distance.