Try using Hevi-Shot loads the next time and make sure you allow plenty of lead. Those big birds are moving faster than you realize and you can easily shoot behind them. The Hevi-Shot hits harder than lead and you can use a smaller shot size which helps your pattern. Shooting Canadas here in Colo., we like #2 Hevi-Shot at 1300 fps or BB or BBB Kent Fasteel at 1500. With steel, velocity really helps.

As far as calls go, the Big River Long Honker works good for me and Cabelas has it on sale for $26. Good luck.