My 220 Swift favorite load didn't come from my experimentation. An article from a Shooter's Digest from the 1970's said that there was never a 220 Swift that didn't like 38.5 grains of IMR 4064 behind a 55 grain bullet. Hmmm...so I got out my reloading stuff and worked up to that load and that is the load that I have used since then. Yessiree...that is a good load.
For the 270, my long time favorite is 59 grains of 4831sc behind a 130 gr Nosler Ballistic Tip.
CCI BR primers in both of the loads above. Work up to both loads since they are near max (depends on the loading book you are reading).