The only problem with that is you can still alt f4 out. The only clear salutation would to implement a 30 sec despawn of your player so even if players alt f4 their character is still in game and can be killed for the next 30 secs. Also on top of that once you disconnect from the server even as a crash or alt f4 you are put on a 1 min timer on the hive so as to check if you are dead.
But the biggest thing you have to remember is Dayz is a combat simulator not a cod, bf 4 fps the twitch aspect is not in play, you have to steady your shot and plan for player movement as well.
Cause this game has more real world aiming, you have to adjust for bullet drop. Also if you are using the m4 or mossie check your zeroing is correct for the distance.
Also make sure you have a working battery installed and the scope is turned on, all this can be done in your inventory menu. Last but not least make sure you have your optics hot keyed in you control config menu.