I use 2230. When I built mine there was data available for the 6x47 Rem (6mm-222 Rem Mag) BR round and it's variation. I also use other 6mm BR rounds with comparable capacities to figure out loads starting way below safe and working up. A few years ago the Hogdon data magazine had an article on the 6mm-204 data in it.
Ackleyman here has been working with it recently.
I. Built mine in 2006, found a good 55gr NBT load for it and finally retired it last year and used the action to build a 20P as I already have 22-204 6x45 and 25-204.