Our wonderful friends over at bf3stats.com are hosting a Gun Master event with some nice prizes. The event will take place on the 31st of August and all you need to do beforehand is to choose your platform and submit your gamertag on their website: http://bf3stats.com/gm

Now of course there are also some specific rules for this as well as an event schedule.

A game round must be played in BF3 Gun Master mode on a ranked server.
A game round needs at least 8 active players.
A game round must not take longer than 30 minutes.
A game round must begin after the start of the stage.
A stage takes at least 60 minutes. The next stage starts at least 60 minutes after the previous stage started.
Their system determines the winners of a game round if they have at least one kill with M320 LVG and at least one knife kill.
Has a stage not ended 12 hours after it’s start, winners of a round are determined from there on if they have at least two JNG-90 kills.
If a stage would start after 04:00 the stage start gets moved to 18:00
A round is counted 30 minutes after it’s end.
For more info on how it is going to be played out, visit the website over at http://bf3stats.com/gm