“Or hunting, in specific situations. I've covered those already. Professional guides separated by oceans, hunting their respective continents, have called them "the best damn bear gun" and "the best damn lion gun" they have ever seen. I cannot argue.”
However, the lever is clearly not the best damn dinosaur gun, because in Jurassic Park, Owen Grady fails to take down the Indominus Rex despite shooting at it many times (and presumably hitting it, since Indominus is a huge target - although its brain is the size of a walnut - with his 45-70 Marlin 1895.
Chris Pratt (the actor) explained that Owen (his character) had the rifle for raptors, which are human sized, so even though it isn’t the appropriate rifle for a Rex, it is what he had when the s hit the f. In a later Jurassic movie, he is better prepared with military weapons.