Velocity spread issues. Bartlein barrel

[Prieto9000]

I used to shoot Berger/H1000 out of my old EDGE and worked awesome, but for some reason on my new build it didn´t. 100yd group was very nice, but ES was close to 50fps measured with my Magneto V3.
Changed to retumbo an SD is single digit and ES is 24 fps. Awesome grouping also!!!
The non marked target is the group I shot with retumbo. Both targets shot @100
My recipe is:
Nosler Brass
Berger OTM 300gr
Retumbo 95gr
CCI 250
BTOL: 3.137"