See the link, I think it will be insightful.
http://www.prairiestateoutdoors.com/index.php?/hunting/stories
If you look at that list of non-typicals, the #1 was a crossbow kill (Bryant buck) #2, #3 were shotgun kills, and the #4 (Jones buck 267 1/8") was killed with a compound bow.
So technically, the biggest buck killed with a "bow" in Illinois is a 267 1/8".
No matter the score that bruiser this guy killed is unreal! Congrats to him for sure.