Are the weapons used in rambo 4 really that powerfiul?

i watched rambo 4 yesterday i liked the movie..just like its previous parts .. this one was full of gun power... did you see the fight at the end? where he uses a machine or something which was mounted on a truck..can it really chop into pieces the way it was shown? and what about the sniper it shopped off peoples head too in the movie...is this really possible? and what are the names of those weapons? and did you like the movie?