Hi Jacob and welcome. The Modified Choke will be the best choke to use for buck and slugs without the need to change chokes for each. Otherwise, Cylinder choke for slugs and Full for buck when shooting independently. Cheers and stay safe!

Good morning Jacob. I would suggest the improved cylinder choke, it usually provides best accuracy for slugs, and is effective for buckshot also. With buckshot an improved cylinder choke provides a good balance of pattern density and effective range.
Stay safe & have a great day!