The HK 91 was a rifle used by Dieter Stark in The Lost World: Jurassic Park. He lost the rifle when he fell down a hill mainly because he tripped over the branches. Dieter died in the end, to be killed by the compys biting him. His rifle was fitted with a scope for better accuracy. The HK91 is a semi auto civilian version of the Gewehr 3.
Heckler and Koch HK 91