I'm shooting an Optima Pro 50 cal. with the 29" fluted Bergara barrel. I am getting 1 1/2" 10 round groups at 100 yards. The fluted barrel is not as heavy as You would think. I'm shooting the 250 grain Shockwave Sabot & using 85 grains of loose Pyrodex. I swab the bore with a borebutter patch before My first shot & between every shot.
I'm planning on shooting some at 200 yards & will post My results.
Andy