As I was reading through the topics last night, I discovered one member's post that described a call to Dillon where the service person recommended not using AA5 - and that got me thinking. Now retired, I've recently returned to reloading after a ten year absence. I have a bunch of powders I haven't tried in the 550B and it would be interesting to see what others think about how the various powders meter through the 550B. So without regard for how the powders perform once loaded. I find that Unique meters poorly and Tite Group is superb. What say you?