best bucket for cleaning out ditches

I have a standard digging bucket for my 426 cat and I have trouble cleaning out ditches. or making any clean cut for that matter. seems no matter how I roll the bucket or pull the dipper and boom up at the same time it just sort of tears the dirt at the inside edge of my scoop everything flops back down into it as I roll the bucket through. I was wondering if a ditching bucket would help. when I watch the township guys go along it always looks so smooth like they are just scooping out a melon. is there something special about the geometry of a ditching bucket?

best bucket for cleaning out ditches