I'm not sure about this but it would seem that deer will need a tighter pattern than say a goose, probally really need more than one pellet in it. I would doubt that you'd want to shoot at a deer all that far with buckshot. I'd think a full choke. Probally a better idea is to go to slugs.I understand that they do well out to 100yds, give or take. Then it's simple, buy a slug gun!
The only experience I have had with buck shot would be using 2 3/4 9 pellet 00 buck shot while using my super full choke I use for turkey hunting. 50 yds was about the limit. My buddy was using same set up only using 000 buck shot and he got much better penetration at the same distance. Shoud be sufficient for your set up. Definitely get the tightest pattern you can.
Your going to have quite a spread at 50 yards with buckshot regardless of the barrel, but full choke will give you the tightest group. Burneke(if that's the proper spelling) rifled slugs would be my choice.
One of the most important pieces of equipment that you will take hunting is a good quality pair of optics and they take some care to give you the performance that you want. So here are a few tips.
Use some alcohol and cheese cloth to clean the lenses. I will usually pick up an extra cleaning kit from my optician when I have my eyes examined.
Don't touch the lens with your fingers. If there is a stick or a bug on them blow it off.
Use the lens covers. They are there...