where to make 10 sniper kills more then 200 meters ?

hy im running out of ideas im sniping away and getting headshots over 200 meters but they dont count up im stuck at 7 

is this because it only counts if yoour doing conquest 64 or 126 ?? i m doing solo /co op 

or do you need to do breaktrough ? and then not solo / co op ?

it also does not work on portals at least in my opinion i saw a youtube video and they did conquest solo/co op but i tried the same maybe something changed in the future and was it an 

old video ?? 

please help me out what to do and yes i under stand i needs to be a headshot with a sniper over more than 200 meters i played larges maps but no sigar 

kind regard dogan