50 Cent: Blood On The Sand
47 Achievements
8-10h
PS3
Explosive
Unlock all special weapons
52.7%
How to unlock the Explosive achievement in 50 Cent: Blood On The Sand - Definitive Guide
Wait until you get 1 million dollars in the bank first, since you get the Millionaire achievement for doing that. Then just buy all the weapons. 1 million isn't enough so you might wanna play through the 2nd last level a couple of times as there is a load of cash in it.
See "Tooled Up"
The special weapons are the R16, G94, Saw 153, Dragon SUV (the best gun in the game).