I can still remember the first minute-of-angle group from a big-game rifle that I ever saw. It was from a 7mm Remington Magnum, was five shots, not three, and it made such an impression that I even remember the handload. (A number of elderly shooters were so shaken on seeing this group that they messed theyselves.) Nowadays, I see big-game rifle moa groups and even sub-moa groups so often that they’ve become routine.
Not so with factory varmint rifles. Back when I started shooting small furred creatures in the 1960s, a good heavy-barrel factory varminter would give you between .50- and .75-inch. Today, not much seems to have changed. I’m currently shooting a brand-new factory .22/250 that is hanging right around .650, and I don’t think it will do better. (If any of you have factory varminters that will beat .500, I’d like to hear about it.)
Such is not the case with custom varmint rifles. With ammo they like, and on a still day, and in the hands of a good shot, they will put five shots into .250–or less. The difference in performance, I think, lies mostly in the barrel. Accuracy is mostly a function of the barrel, and a factory tube has a hard time competing with one that costs $350 after it comes off the rifling machine, before any work is done on it.
I have a .223 built about 15 years ago by Kenny Jarrett that, with benchrest bullets, can put five shots in one slightly elongated hole. This is on a still day, with wind flags, and me not screwing up. The barrel is about the diameter of a freight car axle, and was made by the late Harold Broughton.