Round bar and chefs knives

[Tenkan360]

I'm thinking of making some dyes for.more forge press to make round bar. Does anyone know what size round bar is typically required to make an 8" chefs knife with a 2.25" heel. I usually forge 85-90% to finish but let's just say I'd like to drop that back to 60% for sake of error. I'm new to integral knives so there will be mistakes. Thanks