8 months ago
The Precision Rifle Blog has a very interesting piece up on semi-automatics (in this case, AR style rifles) versus bolt action rifles for precision shooting. It is noteworthy that, according to PRB, “there isn’t a single shooter among the top 100 competitors in the Precision Rifle Series (PRS) using a semi-automatic rifle. Why not? Even though speed, maneuverability, and recoil management are huge parts to that game, the best shooters are all running bolt-action rifles. Some believe that is because AR’s can’t achieve the same precision as bolt guns, so the goal of this test was to quantify the precision difference between a couple of high-end gas guns and a custom bolt-action rifle.”
But they put all of this to the test by comparing bolties and ARs in a side-by-side competition. It’s worth your time to go investigate his findings. He uses the 6.5 Creedmoor for his test, and I’ll comment on this in a moment. It’s also noteworthy that the group sizes look like this.
Now let me speak for a moment on testing for MOA. Barrel harmonics and its effect on bullet placement is a heuristic process. It will follow the Central Limit Theorem. If you shoot three or five shots and claim that your MOA is thus-and-so, you haven’t really given us useful information because you don’t have fractional standard deviation (relative error) and variance of the variance (VOV) information along with the test data for us to ascertain how good it is (and it won’t be good with such few shots). Understand what I’m saying. The more rounds you put down range, the more you will fill in the tails of the distribution and the wider your MOA will be (or at least, you will be able to give us your MOA with its associated standard deviation). There is no such thing as MOA. There is only MOA with its associated standard deviation.
This is a pet peeve of mine, but when anyone – shooters or manufacturer – tells you that a gun is 1 MOA “out of the box,” they aren’t really telling you anything about how many rounds they used to make this judgment. But moving on from this, I’ll note that the high-end ARs are performing very well.
There is another point to be made. I’ll turn to WeaponsMan for his observations.
Money spent on accuracy not used is money wasted. In economic terms, it’s an opportunity cost. 100%, to a first approximation, of shooters, would improve their lethality and therefore their safety in an armed encounter if they put those dollars into ammo, or, especially, training. Yet the guy who balks at taking a pistol class (unless maybe he can take it from a high-speed “operator” who wears designer Multicam down to his skivvies) will drop that money on a tuned 1911. Who are you going to shoot with that 1911? If you’re the late Paul Poole, you shot F-type silhouettes at 100 yards to get people’s attention; if you’re a ranked competitor, you might need that edge when X-rings decide who takes home the trophy. But who are you going to plug with a .45? A burglar in your bedroom? A carjacker in the pax seat of your Prius?
The waste of excessive accuracy is not the only problem with high-precision weaponry. Yes, precision costs money — any gunsmith, machinist, hell, any biologist sequencing a bacterial genome will tell you that. Costs rise asymptotically as you approach the goal of perfection. And yes, all this is bad. Because money is fungible, at the defense ministry or service finance level, a dollar spent on excess accuracy is a dollar than can’t buy training ammo, tank fuel, medical supplies or new radios (or anything else).
But the things that make for optimum accuracy alone may not be suitable for a general purpose weapon. Have you ever wondered why all M1 Garands or M14s weren’t National Match rifles? It’s not just because Uncle Same Numba Ten Cheap Charlie. It’s because some of the NM “improvements” are only improvements for the express purpose of match competition. Tighter parts fit? Hand-lapped locking lugs? A “blueprinted” or tight chamber? A smaller rear-sight aperture? All of these things are wonderful when your target is a bullseye at 500 yards, but they’re no help when your target’s the 10,000 screaming Norks or Chinamen who are coming to take your position or die trying. Indeed, since history tells us that you’ll be facing that human wave in bitter cold, blowing sleet, enervating heat or jungle monsoons, accuracy for a service rifle is defined as practical accuracy that a real-world rifleman (who is not NRA Distinguished or the owner of a Presidents Hundred tab) can employ in real-world combat.
Engineers have a saying for this. “The best is the enemy of the good.” Excess performance over practical specs has uncertain benefits but very real costs.
Yea, engineers have another saying too. Good, fast and cheap. Choose any two. I have chosen the middle of the road. Rock River Arms has a nice competition grade rifle (5.56) with an 18″ stainless steel barrel, sleek barrel shroud and muzzle brake, and it’s not cheap, but it also isn’t top of the line expensive. It’s advertised as 0.75 MOA, and it’s obviously designed for 3-gun competition (as well as some distance shooting competitions). I have one on order as a complement to my RRA 16″ barrel carbine with rails.
Folks, 0.75 MOA challenges the best that most bolt action rifles can do. This is true of 5.56 mm, and I see that the 6.5 Creedmoor bolt actions are similarly challenged by AR designs. I’m not sure that the same can be said of 7.62/.308. In fact if you read the forums on the AR-10, commenters are rather down on the lack of similar design features / lack of modularity, breaking parts, higher expense to get the accuracy, and other things. It may be that accomplishing this kind of accuracy with .308 in semi-automatic invokes the observations about too much expense to get the accuracy.
And 0.75 MOA challenges what I can do with a rifle as well. Other manufacturers have similar designs for 3-gun and target competition with ARs (they usually involve 18″ SS barrels and a muzzle brake). It’s good to see manufacturers closing the gap between semi-automatics and bolt actions on the smaller calibers, but I’m not sure that I expect for this progress to hold for the larger calibers.