Long guns aren't great at shooting somebody who's currently grappling you because it would be hard to get the barrel pointed at them, but that's about it.

Do grenade launchers count as guns?

There is one... but it's incredibly rare.

https://en.wikipedia.org/wiki/Gyrojet

Technically it fires very small rockets.

There isn’t a gun alive that works worse at close range.

FTFY

There might be some edge cases where a round going fast enough to exit a target would impart less energy than a shower round that completely stops inside the target

Probably not the case with a hunting rifle though