I've started to play with OE 1.5 in my CSA .45-90, the grease groove gun, not my PP one. It looks promising at just over 82gr. That's a zero compression load in mine as I'm using a Brooks Creedmoor bullet with reduced driving bands. That rifle has never been as accurate as my .45-70's, but I think with a little fiddling on this new load it'll get pretty close.
Chris.