Well, it's more than just ammo and the "fun" factor. How tight a gun groups is just part of the equation. The other part is how well you can shoot it in a variety of conditions. Try shooting your ultra-light AR10 clone offhand or from a sling. See what you can do with it at 1,000 yards resting it in the fork of a tree. Make yourself up a rack of 8 or 10 hanging plates on a piece of pipe and start out at 200 yards and see how fast you can swing all the plates while shooting off of a pack. When you get pretty fast at it, move 'em back 100 yards more and try it again. Then, when you think you're pretty fast at it, take that scope off of it and get you some good A2 sights (I like LMTs) on that gun and try it again and see how far you can hit 'em. Make a challenge out of it. That's what will make you a better shot. Then, one day you will discover that you are such a consistent shooter that when you do have a problem hitting a target, you know the problem isn't you. And, you also will discover that a gun that can shoot like a laser beam from a lead sled isn't necessarily that accurate a gun when you have to pick it up and shoot it offhand.