Ah, a good rest, calm down, proper hold, relax, squeeze the trigger. Just watch the wind. If you can get a good read on the wind, and read the chart taped to the stock of the gun, it's doable.
I hear ya on the slug guns. I got tired of fighting with my Ithaca Deerslayer II and bought a Tar-Hunt. If I had to do it again, I would have went 20 ga instead of 12.
I hope he walks in range soon!