Semi-Automatic Versus Bolt Action For Precision Shooting
BY Herschel Smith8 years, 4 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.
On July 26, 2016 at 12:52 am, TheAlaskan said:
The 6.5 Creedmoor ballistics are impressive, and, ammo and brass are common….and cheap (relatively speaking,) even in Alaska. I’m building one on the AR-10 platform with a 24″ barrel. I think I just might be able to reach the wolves this winter that always seem to know your rifle’s range.
On July 26, 2016 at 11:37 am, Archer said:
At this point in my “shooting career”, I only need “accurate enough”. I’m getting better, but most of my guns are more consistent than I am. Dropping the cash on a finely-tuned anything is money wasted that could have been better spent on training/ammo/practice to improve my abilities.
Like Granddad said, “You just need a gun that’s more accurate than you are. When you catch up, then you think about looking for a better gun.”
On July 26, 2016 at 2:25 pm, Jack said:
I’m right with you there.
When I used to race cars, there were two kinds of people. Those who blamed their loss on not having the latest and greatest trick racing part, and those who blamed lack of practice.
More range time, more range time, more range time.
Now, if I could only figure out how to build a small range in my backyard…
On July 26, 2016 at 7:47 pm, Haywood Jablome said:
Your Granddad was a smart man! It is my dream to be able to shoot most guns to their full potential!
On July 26, 2016 at 11:24 pm, Blake said:
Ha, yeah, count me as one of those who only needs “accurate enough.”
Jack, that statement is outstanding. I’m going to remember that one.
On July 27, 2016 at 8:30 am, Billy Mullins said:
I got my FNAR mainly for stopping power (post-apocalypse hunting and defense) and because it is semi-auto. The alleged/listed MOA accuracy is a plus. Unfortunately I am not an MOA/sub-MOA shooter so the extra accuracy is wasted on me. Good thing I didn’t choose the weapon for that.
On July 27, 2016 at 3:23 pm, TSA_TheSexualAssault said:
Got a spotter you train with? How are his eyes? Does his optics set cost as much as the scope on the rifle? Is your projected operating area fully-mapped for likely approaches? Just beginning on the non-rifle time/money that might be more worthwhile than supreme rifle accuracy.
Mac vs. Windows? rlly? What about the lessons being taught us by illiterate tribal people and former Iraq Presidential Guards? ps: It’s not about carbon build-up in the piston area of a Belgian rifle.
People problems are not solved with hardware (but…I love hardware!), as long as two teams exist. This was the Soviet solution in Afghanistan (no Afghans? No problem!), and it would have worked if not for Congressman Wilson.
On July 27, 2016 at 3:23 pm, Merle said:
Glad to see someone use some common sense when it comes to gun purchasing. Very few people shoot like Navy Seals and could certainly spend their money wiser on training and good ammo. I have some expensive rifles and optics but my go to weapons are middle of the road. Buy extra mags, if you have the money buy some NVG’s. Night vision is a game changer in my opinion. You can’t hit what you can’t see. My favorite close in weapon is a Sig 226 TacOp with IR laser and Gen 3 NVG’s.
On July 27, 2016 at 4:09 pm, unpundit said:
“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.”
I really don’t see why not.
Perhaps this should be the subject of the next test.
Drop a good barrel into a standard DPMS or Nemo high-caliber AR platfor, and see what happens.
I suspect the bolties will win by an equally unimpressive margin.
On July 27, 2016 at 4:19 pm, Herschel Smith said:
Maintaining the tight design tolerances on the moving parts associated with a semi-auto so that cartridge pickup, seating and ejection can occur seamlessly in the presence of greater forces.
On July 27, 2016 at 5:06 pm, Fed Up said:
Unless everything else was identical (barrel, trigger, scope, bipod, etc, etc) then this comparison is BS. Want to compare semi auto to bolt action? Then compare the action and nothing else.
On July 27, 2016 at 8:43 pm, Paul X said:
I can go along with most of this, but I think confidence plays a role too, and it is easier to be confident with a more mechanically accurate gun. That way if you miss, you can only blame it on yourself, not the gun. So while I agree one can go overboard with spending on precision, some *reasonable* amount of precision is probably not throwing money away. Better to have a gun you have to work to shoot up to, than one that is already worse than your abilities.
On July 29, 2016 at 4:31 am, Louis Chapman said:
I have a rock river varmint a4 in 308, and it drives tacks.
Then again, it’s also got a bull barrel, proving that you can make anything accurate if you’re willing to make it absurdly heavy. And while it holds. 75 moa all day long , my bolt action savage out shoots it, weighs less, and cost half as much. You seem to be missing your own argument here. Your title regarded precision shooting, and then you devolved into the minute of man / practical accuracy argument. ARs and AKs are indeed “good enough. ” but the bolt gun remains king when precision is the name of the game.
On March 8, 2017 at 5:45 pm, LilWolfy said:
I’ve had more malfunctions with an M24 in a day than I can ever recall with M16s and M4s. I also see a lot of malfunctions at PRS and long range matches when I RO, like at Steel Safari and local matches. Everybody is using bolt guns. Some of the problems are of a DQ or “you’re done” nature.
Normally it is easier to correct a malfunction with a bolt gun because you have direct access to the action, unless it’s a fire control or mechanical problem that requires disassembly and armorer work. I’ve seen several of those.
I would like to see more matches that require precision and speed, like with movers and multiple target arrays where you’re on a timer.
On March 8, 2017 at 5:55 pm, Herschel Smith said:
I think there are some 3-gun competitions now that require longer distance shooting, making the competitors think about transitioning to higher power scopes (perhaps some are using 6X now?). I have a 6X on one of my guns, although I don’t do 3-gun (would love to, can’t find the time).