Shotguns need fixing not nerfing - if you run around with another weapon that can also kill with 1 hit i.e. 338-Recon as I often do its quite apparent that there is something not quite right with how the game reconciles the player histories involved - you need to kill a player with a shotgun a good 500-600ms before they fire or they will always get the kill and your shots in the relevant timeframe will always count for nothing (even when in reality your reacted and shot - even if you adjust for latency - before they did, have a lower latency connection to the server, etc.).