The only shot gun I have is a Remington 870 pump with a full choke (fixed, of course). It's marked for 2 3/4" on the barrel. I don't have a clue what to use for shot size, though. I picked up some of the Turkey Thug shells at Walmart, and realized they were 3" when they wouldn't eject (obviously I wasn't very detail-oriented when I bought them).

I switched to my target loads once I realized it because that was all I had at the range yesterday, and I did my best to pattern and sight with those. It's possible that I could have some time today to go try to pattern and sight again once I get a good recommendation from y'all, but I don't know.

Can I get some advice on this situation, including shot size?
No hunt is all skill. If not for a little luck, no one would hunt.