Average dispensing time of 60 grains of extruded powder is 30 seconds
600 Overkill
Lyman in the last ten years bears no resemblance to the Lyman of the 1970's.I'm still using a Lyman #55 that I bought in the early 70s, don't know why they would be getting bad reviews.
I think hornady makes one for the 50 bmg that might be in your range.
This should work!
It's a little pricey though!