The 243 SuperLites are notorously poor groupers. As a truck gun goes though, just how well does the gun need to group? The real question may be how well does the gun put it's first shot in the same place everytime. As a hunter, I look at that as much if not more than how it shoots groups, particularly groups of greater than 3 shots. I have yet to find the best load for any gun in just a couple of days. Ihave spent as much a six months working with a Handi to find it's sweet spot, and I've seen it with the first load I fired through the gun. While my 38-55 shoots several loads well, there are several loads it doesn't shoot well. Just because a gun doesn't shoot well at first doesn't mean the gun is bad, nor does the first shots through it going less than an inch make it a great rifle.
I am currently working with my friends 243 using cast bullets. The rifle is scary accurate, I've done nothing but some trigger work, you only have to stand on it make it fire now. Meanwhile the best Ihave seen my 357 Max shoot at 100 yards is 2" (5 shots). It'll do that nearly on demand, and the first shot is always within 1" of POA, that is over 2.5 years, that's good accuracy. I can hit anything I wish out to 150 yards no questions asked. Groups are not the only measure of a rifles accuracy.