I use a Dillon power trimmer with whatever rifle brass I can. Unfortunately, short cases like 300blk, 7.62x39, 6.8/224 are too short for the stock Dillon die. However,
www.ch4d.com will make custom dies for it.
I just got a .224 die prior to moving to a new house, so I haven’t set it up yet. I have used the .300 and x39 dies and they work exactly as expected. It takes some setup, but it’s positive and consistent. The throughput once you have the Dillon set up is great.