That shoots a pair of Nitro Express cartridges the size of bananas. It's designed for knocking down elephant... not just wounding them, but knocking them base-over-apex.
11 seconds sound clip from the X Minus 1 - A Gun for Dinosaur by L. Sprague de Camp classic radio drama series.
You can hear this line at 00:03:03 in the radio play.
Quote context
[...]
- I'll get you a shot at any entelodont or even mammoth or mastodon... and they have fine heads.
- But I'll jolly well not take you to the Jurassic or the Cretaceous. You're just too small.
- Well, what's my weight got to do with it?
- Now, look here, old boy, what did you think you were gonna shoot those dinosaur with?
- Well, look over here in this case. That's my own gun, a Continental six hundred.
- Well, now, I've handled guns.
- Look, I've been guiding hunting parties for over twenty years.
- But I've never known a man your size who could handle the six-nought-nought. It knocks him over.
- But people have killed elephant with lighter guns, even a three-seventy-five.
[...]