I bought the game a couple weeks after launch, and I spent most of my first 5 pretiges just unlocking attachments for every gun, so I'm just now getting into the whole gold/diamond camo business.
I'm working on the Skorpion, and it just doesn't ever get headshots. With the MP7 I could hipfire and aim vaguely towards the head and get headshots at a decent rate, but no dice with the skorpion. It's like one headshot every 3 games, typically with 15-40 kills per game depending on what game type.
If I recall the Skorpion has a low/nonexistent headshot multiplier, so I'm guessing that's the culprit. Getting a headshot doesn't count for extra damage and thus have a higher chance of being the killing blow, but still. It's going to suck using this gun for like a week.
I suck at getting headshots for those challenges. I usually get one headshot at most per game. Sometimes I'll go the entire match without a headshot. I was also trying to do the Scorpion challenges, so I averaged like 10 headshots per day. Finally when I got to 100, I decided to switch over to the FAL as my main weapon before I got the Gold camo. <_____<
I dunno, a lot of times I feel like I'm aiming for the head area and I still won't get the headshot. Sometimes I'll even get free shots at snipers standing still and don't see me behind them, and I still don't get the headshot even when I was sure I shot them in the head. It was really frustrating.
I guess my advice would be to take it slow, and don't try to do too much in one day. Concussions definitely help get easy headshots, so run concussions with Scavenger so you can replenish a concussion with every kill. Definitely be sure to take advantage of those guys standing still who don't notice you sneaking up on them.
Wait I got it! Super Mario 3D Land will be in California and Super Mario 3D World will be in Florida. Zing! ~AloofGuyXXVII