Hy friends.
I am starting to compete in bench rest with my steyr ssg 69 on 308 so my concern is to get the most small groups as possible.
At the moment I make 5 shoot groups in 2 inches at 300 meters(1/2 MOA) in this conditions: about 11.000 ft high. (Andean mountains) 670 mbar 15 to 18 deg celcius.
Sierra match king BTHP 175 gn 2350 fps.
At this distance, shoots are in the winning zone, but a very small variation can place one hole otside of the center, orvthe group will not be so nice at 400 meter and londer distances.
So I was reading a lot of stuff, and twist /stability is one of my concerns. I found the Bergers calculator which tells me the stability of my bullet is very very good, but other articles recommend a twust of 1:10.
I know twist rate vs bullet weight is an allready discussed theme, so my question is about your experiences with the reliability of this calculator, but I also hope you can share your twist rate/bullet weight experiences at medium and long range shooting with 308 if you also have a 1:12 barrel
Thanks a lot