I just got my 270WBY together with a 25" Bartlein. Only two range sessions and just today with Chrono.
I only want to use 150's.
RE22 is accurate but 69.5grs with a 150BT is only 3050. Factory 150 Spire Points go 3130-3140.
I'm going to bump it to 70grs and also try about 72grs of 7828. The one load of 7828 I tried first time out was least accurate but still was 3/4'ish. R22 will drive tacks.

If I can get 3100 with a 150 at 1/2-3/4" in a 7.5lb scoped 270WBY I'm in heaven...

I may try RL25 although I have tried it in several rifles without any success, yet. (WBY's and 7mags).

Dave

But as for me and my house we will serve the Lord. Joshua 24:15
I can do all things through Christ who strengthens me. Phil. 4:13

I DON'T NEED A WSM AS I HAVE A WEATHERBY!