People give the Mauser K98 too much credit for what it was. It was a short, light combat rifle, with a painful recoil. Great accuracy, of course, and the ammo was quite powerful, but still, it comes nowhere close to the original...
Mauser G98 (Gewehr 1898, or Rifle 1898). This is the king of them all, people. Full stock. Better recoil. More accurate than any combat rifle ever made. Smoothest bolt action in history. Oh, and my grandpa took one as a souvenir from a deceased German soldier in WWII (yes, Germany had many G98's in use in WWII, more than the K43, or G43, in fact).
It had only been fired about 4 times before my dad sold it.
Anyway, the Mauser G98 is the German rifle that should be mentioned in all of these topics, not the K98. Oh, and don't forget about one of the finest Muskets of all-time... The 1810 Prussian Potsdam (percussion version). Not even close to being a rifle, but it's still worth mentioning.
The G98 wins the long-range firing battle... But for close quarters. I would take the AK-47. It's very tough, rugged, and reliable.