Disclaimer for all those handy with your negative votes:
This is not a 'legit' way to get it. I think the achievement speaks for itself if you want to do it in regular lobbies, but if you want the achievement without the hassle, the game has given you that opportunity. Here's my way.
Set up a match with a single bot.
Down him, plant a frag on him (Note that you don't start with frags) then use him as a shield before he blows.
It won't damage you.
Rinse, repeat ten times.
UlteriorDesert - "You can also change all weapons to frags and get wins on all the maps"
If you negative vote, please let me know why.