Irons, Dots, or Scopes? There's Data on That!

An all too common discussion, or argument, is what is the best category of sighting system for infantry arms. There are a lot of traditionalists who insist iron sights are best, and much discussion of whether red dots, fixed power scopes, or LPVOs (low-power variable optics) are best. 

Well, a couple years ago the US Army Research Lab (ARL) actually did a very relevant study. Their plan was to determine if a universal zero or soldier zero is best. Now while that's not the focus of what we care about, to avoid you being distracted we'll talk about that briefly. Soldier zero is what you do with your gun, or what the US generally does; the individual zeroes his gun for himself. A Universal zero means the armorer zeroes the rifle for you. For example, the reason the G3 has a weird sight tool is to make sure soldiers in the field can't mess with it, as only armorers are allowed to zero the gun. On purpose. 

But to get there, they did a test of how well each of those zeroes worked... on four different sighting systems! 

That means we incidentally got data on how well each of those sighting platforms work, on the same gun, with the same soldiers shooting, under the same conditions. For those not 1000% familiar, I'll summarize which is which: 

• Standard M4 Carbine Iron Sight — The MATECH flip up BUIS (Back Up Iron Sight), but basically an aperture or peep sight, with a range dial. 
• Vortex Razor 1-6x — I guess because 3 years ago, off the shelf, not type classified scope. The defining characteristic of the LPVO is the bottom end is 1x, and ideally is like not looking through a scope at all. Also usually with an illuminated reticle, bright enough to be seen during the day so it sorta operates like a red dot sight at 1x. Reticle is not specified but will likely have a way to hold off for range. 
• M68 Reflex Sight — The Aimpoint Comp M... something. They use "M68" for all of the several generations. I assume nothing based on the photo, but all Aimpoints are pretty bog standard RDS, or Red Dot Sights. If you think the holographic EoTech is very different, it's not. All Reflex/Collimator/Holographic/RedDot sights are about the same. No reticle, just a dot. No ranging ability. 
• M150 Advanced Combat Optical Gunsight — A normal 4x ACOG, the newer one (replacing the TA01) is this, the TA31 (Army) or PVQ-31 (USMC). Fixed power, illuminated via fiber optics and tritium and no diopter adjustment for the individual shooter's eyes. Has a BDC reticle to adjust for different ranges if fired off the expected platform (M4) with the proper ammo, and everything is as planned. 

And the results? Lots and lots of stats. Let's not worry about them, and don't agonize over the number of participants. I do some research for a living, and for the type of study, and the results and analytical methods chosen it is fine. These are valid results. 

Biggest takeaway: Irons are terrible. As we've known for individual programs back to the late 1940s, anything is better than irons. Even at 100 m on a range, notably worse results. As I was once told, "Falklands experience confirmed that at 400–500m, even when you had the ballistics to threaten the foe, iron sights and fear were a bad mix for getting hits (we didn’t do badly - after all we won - but we did take a hard look at what worked well and what could go better)..."

As range increases, the next most obvious thing occurs, in that the red dot begins to suffer. This is likely the direct result of no magnification, so the shooter's eyes are doing a lot of work. 

The M4 and ACOG are optimized for about 300 m distance, and it shows here, with a notable dropoff in accuracy, nearly to RDS levels, at 400 m. 

The LPVO is the best as range increases. Likely because of the small additional magnification, but there may be something else such as dialing vs holding ranges. It's unclear, and would be good to observe people shooting such a test. 

One last note is that they did not test a magnifier behind the M68. That should have provided similar results to the LPVO, but it would be good to try out. 

Read the whole study if of a mind:

Effects of Sight Type, Zero Methodology, and Target Distance on Shooting Performance measures While controlling for Ammunition Velocity and Individual Experience

ARL (US Army Research Laboratory) TR-8594 (December 2018) 

Or bookmark the whole CWG library of info like this.

Using this Info For Swift Fox and other CWG events: 

Due to the limited range of the simulation systems we cap all magnified optics at 4x. But even then, we've seen the reduced-range version of these results as everyone brings their own guns and so we see a broad range of sighting systems. This sort of thing (or classes, or so on) is one reason that these results are not at all confusing and in fact the conventional wisdom. 

Even at closer ranges, there's a notable benefit to optics. While a red dot sight would seem to be enough, the research also was on a flat range, but we've seen magnification be helpful at least as close as 50 m, to see through brush, or pick out camouflaged individuals moving slowly under partial concealment.  

For Swift Fox 23 we'll be back on the ground, in the woods of Oklahoma. Try out your weapons systems and skills April 21-23. Sign up today.