About the 7383 ...
It ain't similar to other canister powders due to the flash suppressant.
Nothing scary about it. It is sensitive about being taken out of its happy zone. The happy zone is 38,500 psi. If you go with less it will be dirty. If you go more it gets unhappy. Once you pass 40,000 psi it becomes unpredictable. By burning the powder outside & above it's designed pressure application you are changing the burn rate, essentially teetering on a much faster burn rate by overcoming the flash suppressant. That's when things go south quick & my layman's attempt to articulate what's happening.
I've burned 21lbs so far in 223 thru 308. I've heard it said many times "you can't over fill that case with it". That is untrue for most situations. Any case that can generate more than 38,500psi with it can be overfilled. It always shows pressure signs if exceeding the happy zone.
Loads must be worked carefully. It actually works pretty good in some cases. I've a some for x39, 3030, &308. Bullshop really liked this powder in the 308 & shared some useful tips on the old site. Once you get near compression you don't want increases more than 1/10th of a grain at a time, it will show you where your at.