I was reminded that the percentage of slow or fast is not really known yet.I was hoping this would fall around LVR/CFE223 burn rates/pressures. There's a ton of cartridges I shoot that would be "optimal" in that range, but I hate the temperature sensitivity of those two powders, and RL16 is just a tad too slow with the case volume available. Based on Alliant's load data, I would have expected this to be a touch slower than Varget, not so close to RL15. That's really unfortunate.
It may work in cartridges you need it to work.The only way to know is to try it since you have some.
This Saturday morning I am starting on my 30-06 trial loads to see if it's too slow for 152 gr H H.