Road Razor (Roadblasters - Matchbox - 1987/1988)
I have no memory of Matchbox going all Mad Max! :D (though I did own most of the vehicle models they used for them).
@MrRobotoUK Looking at the dates on the undersides, the cars were made a good few years before. I guess it was a good marketing idea. It was the 80s way. Take something and shove loads of guns on it. These were huge at my school, for about two weeks anyway.