I've killed quite a few big game animals with rifles that wouldn't average any better than four inches at 100 yards--if you count shotguns with rifled barrels for shooting slugs as rifles. (Dunno why not....) They work fine as long as the range isn't beyond minute-of-deer.
One, however, was a rifle used on an"industry" deer and pig hunt in Texas. Actually, the rifle shot fine, as it was a Remington 700 in 7mm SAUM--which I'd already purchased at the writers' discount, after testing it thoroughly with both factory and handloaded ammo. But the scope chose the Texas hunt to go screwy, which I discovered when range-checking the zero down there. The scope didn't totally fail, as quite a few others have on my rifles, but groups with factory ammo that normally shot into an inch or a little less were around 3-4 inches. So I hunted with it as if it were an open-sighted lever-action, and not only killed deer but one feral pig, plus a javelina, none of which were over 100 yards away.
