Cheers for that Hartley! They didn't ask him if he 'zeroed' the sight. And I wonder why he was never asked to be a witness?
He does refer to previous statements though. Maybe further insight is contained in other statements.
I think this zeroed thing is a bit of a red herring, the rifle would have been zeroed in by somebody, it doesn't really matter who it was. Even if the gun shop did do it, it's likely it would have needed to be repeated at some point in the 9 months since purchasing it (depending on use).
Would there be any point in calling him as a witness?