That gun is an economy version of a Benelli Nova. I'm not sure what the exact differences are. I've worked on a few Nova's, they have all been "clanky" with a very distinctive trigger sound. They are great guns in the field and in a blind, not the set up I would use for shooting sabots with a scope.
He should run a bunch of rounds thru it and that will smooth things out a bit.
Cheers!