Range Report DB 10 308 Win. - Accuracy Issue

[madpat]

I was at shooting range today to test different ammunition and I have big accuracy issue, any idea what could be a problem and how to fix it?

one square has 1.0 cm - 0.39" - 1/3moa

Specs:

DB10:
18" stainless steel barrel 1:10'
Standard trigger with softer JP springs
Harris Bipod 6-9
Vortex PST 6-24x50 FFP
Vortex Precise mount with 20 moa cant
Magpul PRS stock moded to fit in db spring tube

Photo of accuracy on different ammunition

PS I use bolt rifle too and don't have accuracy problem (usually 1/3 - 1/2 moa)