Ask Seafire, but Blue Dot is high performance and goes over the top like a light switch. My pet BD load is 13.8 in a 223 under both 35s and 40s and pressure manifests really quickly, not at 13.9 but absolutely at 14. I'd not be shy backing off, it's hot stuff. If you have a chronograph, you'll see velocity stop climbing and scary things starting to happen. Might be the pressure curve under a can is "that" tiny bit different. Again, Seafire posted a ton of good numbers for all of us, and others have reported back and pretty much verified Seafire's experiments.
My practice is to make a batch of singles at grain increments of one tenth, five tenths around Seafire's favorite, and carefully shoot the series, tracking each impact in a notebook target. Usually, three are close together and those after, I've never gotten more than two tenths past that point without seeing or feeling "something" and therefore calling it good. The load is usually the lightest of the cluster, and it's usually VERY good.
Velocity with Blue Dot is not the point. The point is efficiency, accuracy, lower temps and relative quiet.
