Re: 270 wsm bergers
I have used the 140gr Bergers in 270 WSM and consider them a go to bullet. I never found the velocity with 150 gr bullets to compete with a maximum load of MagPro. I could get 3400 fps from a 28 inch barrel in my 1885 Highwall (Miroku Mfg).
What is your powder, primer combination?
Do you have a 1 in 10 twist?