Sako 300 Win Mag Issues?
I have a Sako rifle with a Hart 300 Win Mag 1-10" barrel. I have struggled with consistent accuracy from day one. One day the rifle will shoot a particular load into 0.5". I'll load some more and they now group 1.5". I have tried H1000, H4831, H4350, Rx22, Rx17 and IMR7828 powders. For bullets I have tried Berger 168, 175 and 185 VLD Hunting, Nosler 150, 165 and 180 AccuBond and Hornady 150 165 and 180 Spire Point, Hornady 165 SST and 180 Inner Bond.
I have also tried a different scope.
My friend suggested that I should put the expander button in my Redding Type S full length die as without turning necks I will get inconsistent bullet pull without it. Redding post this on it's site:
Question: Do I need to use the expander button that came with my Type "S" Die?
Answer: It is advisable to use an expander button to maintain consistent neck tension if the case necks have not been turned to a uniform wall thickness. However, the expander button can be replaced with the Decapping Pin Retainer (included with your Type "S" Die) if the user does not wish to use an expander button.
so I guess he is correct. I installed a carbide expander button but accuracy still remains inconsistent.
The barrel work was done by Dan Dowelling and the rifle was bedded by T&M Stock Works. Just to be sure I had the rifle rebedded and recrowned.
I have tried different seating depths and have measured my bullet runout at 0 to 0.002" max.