Who does the art concepts of the CF Guns?

A bit of an odd question but i do digital painting and recently i have been drawing some of the guns from crossfire (Not done yet). I just wanted to know if it's ok...Who is the person or people that make the concepts of these new guns? Do they have an online portfolio or anything i can check out? Who ever it is they get very creative with there ideas, especially like the m4a1 pink guitar.