How do i use custom gun models?

hello,i am very new to game creation,i have made models of weapons in maya 2013,and i now want to bring them into the unreal engine 4,so how do i go about switching out the blue default gun with my model from maya?I want it to be in first person mode with iron sights.i have already imported the models from maya to unreal as fbx static meshes.also,is there a way i can apply materials to different parts of the gun?after i import the model i can only apply a material to the whole gun,but i need to apply different materials to differents parts of the gun,i have searched google for tutorials but have found nothing,any help will be apreciated

I think this video will answer your question: