Ok, you are shooting good groups with factory and not shooting good groups with reloads that are jammed or tight to lands. First immediate thought is this rifle prefers SAAMI COAL thus significant jump. So I would measure the CBTO of the factory and load similar CBTO to determine if this rifle just prefers jump. Sometimes we don't let the rifle tell us what it likes best or maybe we are not listening. I have a 300 WSM that shoots Nosler ABLR 168's at SAAMI by far the most accurate so heck of jump. Same with Sierra Gamechanger 165's. Close to lands doesn't always get it done best.
