Help with history on 8mm mauser?

[haf]

I recently inheritted a 8mm mauser from my grandfather. He got it from his father who I think brought it back from the second world war. It is a model 98 and says k98 Germany 8mm on the front of the barrel. On the top of the gun is says ar then 42. I assume the 42 is the year it was produced. All of the numbers on the on the barrel and reciever match but there are no markings anywhere on the stock. I was just hoping to find out some history on the gun like what the ar means and if it was used by the nazi's. Thanks for the input