Calf Training

Hey!

I was just wondering if anyone has advice to share on effective calf training? I try to do intense calf work at the end of a workout at least once a week, other than regular leg day, and usually go high reps/lighter weight on bent knee (slow twitch?) and lower reps/heavier weight on straight leg (fast twitch?) and I really try to burn them hard. Seated 4 sets, straight leg press raises for 4 sets and maybe I'll do burn outs in between using body weight on stairs... I'd say my calfs (calves?) are okay defined, especially when pumped but I can't seem to break 15 inches which almost an inch smaller than my arms.. don't want to be a chicken rider lol