I think something needs to be taken into consideration that may be escaping some of us. When I started shooting muzzleloaders almost all of them were 1 in 48” twist no matter what caliber they were. When I got my old CVA Mountain rifle that was 1 in 66” I thought I had died and gone to heaven. But it didn’t stop there. Soon barrels were being made in 1 in 72” twist which although they shoot well, require a bigger charge of powder. About the same time the barrel companies changed the steel they were using, and started making barrels lighter, which made for more felt recoil. But, it also pushes the envelope when it comes to pressure in those thin barrels. The end result if the barrel doesn’t rupture is the light barrel with the big ball, and big charge, kicks the snot out of you. Which makes your groups grow progressively larger, because you are anticipating the recoil.
Hungry Horse