I've shot all factory loads through my ultra,,cause I don't reload,,and they all group to an area that would be a kill on most game animals. But,,I am also thinking that this gun will never be a tack driver as I had hoped. Maybe we all need to reload to do that,,but I just don't shoot the 243 enough to make it economical.
The ammo I liked best.......Hornady 75gr hp...58gr vmax. The 100 gr Win sp didn't do bad,,,like I said it would kill,,,and I didn't adjust my scope to make it group better since that's not the ammo of choice for me. The Cabelas bulk 75gr vmax isn't bad either for the cost...but it groups 4/5 inches. Also some 80gr sp by PMC shot okay.
Great looking gun........heavy on the shoulder when walking,,,I've got a 8-32x50 Swift Premier on mine so that adds a bit of weight too.
Hope this helps.