One thing to keep in mind about the "approximate burn rate" charts in the manuals....they are based upon the burn rate "at moment of ignition", and don't account for the powder's "vivacity", which is its burn rate once it's under pressure. Most powders increase in burn rate once aflame and under pressure, and at that point, the burn rate listed in the manuals doesn't mean much.
For example, according to most burn rate charts, IMR4350 is "faster" than H4350. But, once ignited and under increasing pressure, H4350 reaches it's peak faster and "holds" this pressure curve longer. And a projectiles "time under pressure" is a major contributing factor to it's final velocity. You can actually get noticeably faster velocity with the Hodgdon powder than you can with the IMR powder, all else equal, and given suitable bullet weights.
Mike