Lawdog, I confess , I still use a 222 Rem. Mag. It is my "second" / alternate prairie dog rifle. When the first one gets too hot, I switch and hope the first has time to cool before the 222 mag gets too hot. Anyway, it is a 40+ yrs old Sako vixen that I was given as a youngster. I think I am shooting about 27 grs. of Ramshot TAC behind a 50gr. VMAX. Velocity is around 3400 and it has a wonderful way of "elevating" a prairie dog's day. I occasionally use the 50gr. Blitzking which is awesome, but just a bit more expensive than the Vmax's. Even this old Sako will still shoot sub-moa groups. IMO the 222mag is a good solid caliber that exceeds the 223 by a wee bit, but sadly its lack of popularity has made it almost extinct. Thanks be to the 204 Ruger for extending the manufacturing life of its brass. If you are looking to build some loads use a grain or so under the 223's max loads for a starting point.
TAC and H335 are good powders for it. Hope this helps.