I have 7 CA. CARBON RIFLES AND ONE NOSLER 30 WITH PROOF RESEARCH BARREL AND AS OF RIGHT MOW WE HAVE TRIED AROUND 7 DEFERENT BULLETS AND 4 TYPES OF BRASS AND NOSLER FACTORY AMMO AS WELL AND STILL DONT HAVE A GOOD GROUPING WITH THIS RIFLE . WE CAN GO SHOOT IT ONE DAY AND GET 1/2" grouping and we reload the bullets and go back the next day and it's around 3 to 4" so I,m not sure right now whats going on with this rifle I,m hoping we can get it figured out after about 1000.00 dollars of trill and area