If you shop for gun scopes, you will see the abbreviation MRAD. Sometimes, you will see MIL, which is the same thing, just different letters. MRAD = MIL. I will use the term MRAD to make things easy.
MOA is similar to MRAD but still different. MOA is also an abbreviation. It stands for Minute Of Angle (MOA).
When used in the context of gun sights and scopes, MRAD and MOA refer to measurements. Each one is figured a different way, and each one represents a different space, length, or distance, depending on your choice of words and measurement needed.
Look at a scope and the measurements it uses. Every scope has a reticle. You change the position of the reticle using the adjustment controls. These adjustments are also called click value because, on traditional scopes, the knobs click as you move them.
Milliradian
MRAD is the abbreviation for the word milliradian. Strictly from the math side of things, MRAD is a measurement of an angle. It is based on the metric scale.
When talking about gun scopes, MRAD is a measurement of distance. For our purposes, 1 MRAD is 1 centimeter at 100 meters. The best gun scopes offer click values in 1/10 of an MRAD.
Putting this in Imperial measurements (American), an MRAD is equal to 3.9 inches at 100 yards. At 100 meters, the MRAD is a tiny bit larger because 100 meters is a longer distance than 100 yards.
A scope with 1/10th of an MRAD adjustment means the reticle moves .39 inches at 100 yards and a hair more at 100 meters.
On the Imperial scale (American), a centimeter is .39 inches, and 100 meters is 109.361 yards. The difference between 100 yards and 100 meters is around 27 feet.
IMPORTANT – Do not get caught up converting inches to centimeters and back. Your rifle scope does not do the math. Sight your gun in at the range you want to shoot. Then, learn how to shoot at different distances using that scope.
Artillery
MRADs were developed for the military. When shooting cannons and big armaments, the gun’s barrel is moved up and down to change the elevation. The movement is measured along an arc, and MRADs provide the precision needed for such large weapons of war.
Big guns often have an angle dial on the side or somewhere nearby so gunners can compute the needed degree of raising or lowering the big guns.
The military still uses MRADs, and many law enforcement agencies also use the MRADs in their sniper weapons.
MOA
MOA is also a measurement using angles. It is the abbreviation for Minute of Angle.
For shooting and scope purposes, an MOA works out to be about an inch of distance at 100 yards. If you want to be exact, it is 1.047 inches at 100 yards.
Going from Imperial to metric, 100 yards works out to be 91.44 meters.
Most civilian scopes use MOAs for the adjustments. The most common click value is 1/4 MOA. Some sniper scopes offer 1/8 MOA. A few have ½ MOA, and some red dots have 1 MOA click value.
More Precise
If you read the above carefully and do some rudimentary math, you will see that a scope with ¼ MOA click values offers a tighter adjustment than a scope with 1/10 MRAD.
You are looking at ¼ of an inch (MOA) vs. about ⅓ of an inch (MRAD) at 100 yards. Yes, ¼ of an inch is smaller than ⅓ of an inch. Here is the math ¼ + ¼ + ¼ + ¼ = 1 inch. For the ⅓ equation, ⅓ + ⅓ + ⅓ = 1 inch.
Using decimals instead of fractions, an MOA is .25 inches. An MRAD is .3333 inches.
Strictly on the numbers, MOA offers more accuracy than MRAD. But is that difference really enough to matter?
No.
Reach this out to 1,000 yards. At that distance, a 1/10th of MRAD is 3.6 inches. An MOA at 1,000 yards is 2.63 inches. So, at 1,000 yards, there is a 1-inch difference between the two.
For comparison, A typical mouse’s body is between 2.5 and just over 4 inches long. The current world record for a 10-shot group at 1,000 yards is 2.6566 inches.
Military
So why does the military prefer MRADs? Consistency. Using one set of measurements means rifles and artillery are using the same formulas when making adjustments.
A sniper’s spotter can call out needed adjustments to a shooter and, if needed, call adjustments to gunners manning the heavy weapons. By using 1 measurement system, the spotter does not have to switch back and forth between 2 systems.
In the middle of a battle, swapping back and forth creates unnecessary confusion.
Bullet Size
Compare MRAD and MOA to a bullet size. Caliber is a 1:1 ratio with inches. In other words, a 1 caliber gun has a 1-inch bore. A 22 caliber bullet, if measured exactly as a 22 cal, is .22 inches across.
In the metric system, 1 caliber is equal to 2.54 centimeters or 25.4 millimeters.
So why are bullets in diameters of .308, .310, and .312 called 30-caliber bullets? Why is the .44 Mag round actually a .429 caliber? Because people do not make sense. Anyway…
An MOA at 100 yards is almost the same diameter as a 25-caliber bullet shot in the .25-06. An MOA is a bit smaller than a 6.5 Creedmore and a hair bigger than a .243.
An MRAD at .39 inches is just slightly bigger than a 9mm Luger bullet, which has a diameter of .355 inches. It is a tiny bit smaller than a 10 mm or .40 S&W. Both are .4 inches in diameter.
Which Is Best?
When talking about MRAD and MOA scopes, you want to know which is best.
Whichever you feel more comfortable using is best for you. Some shooters want MRAD. Some want MOA.
How your scope handles measurements is truly irrelevant. What matters is the quality of the gun, the ammo, and the person behind the trigger. Scope quality for accuracy matters only when it comes to the ability to hold a zero over time and many shots.
The world’s best scope, in MRADs or MOAs, on a gun with a bad barrel, poor ammo, and mediocre shooter (or any combination) is not going to deliver accuracy.
On the flip side, an average scope on a superior gun, precision hand loads, and in the hands of a sharpshooter is going to bang the gong every time. Or, it will as long as the scope holds up.
Why 2 Measurements?
This begs the question, why do scopes have 2 different measurements? The reason for the MRAD is explained above; it is what the military uses.
The reason for MOA is America. Americans use the Imperial system for measuring things. Most Americans understand inches and fractions of an inch far better than centimeters and the rest of the metric system.
Since MOA is so close to inches, Americans are just more comfortable with that than MRADs.
Get outside the US and most shooters use the MRAD system because they are more familiar with the metric measurement system.
Both systems are based on measuring angles.
FAQs
The best choice for a gun scope, MRAD or MOA, is entirely up to the shooter. The quality of the scope is far more important than how the reticle is adjusted.
MRAD and MOA are not interchangeable. They are similar. One can be converted to the other with the proper math formula.
You use an MRAD scope the exact same way you do an MOA scope. You sight it in by making small adjustments on the windage and elevation turrets until you are on target.
MRAD and MOA are equally accurate in a gun scope. Accuracy is a function of the gun, ammo, and the shooter, not the scope. The same gun with no scope, a bad scope, and a high-quality scope have the same accuracy as any of the three.
Conclusion
All of my gun scopes are MOA; I have nothing against MRAD. I am just more familiar with the MOA measurements. I grew up with MOA. As I am approaching senior citizen status, the idea of learning a new scope setup is not appealing.
Also, I am spectacularly bad at math.
If I ever get into extreme long-range shooting, 1, 2, and 3 miles, I will likely get an MRAD scope. The highest quality scopes from Europe are made on the MRAD platform.
Since I’ll need a scope that can handle that kind of shooting, I will get MRAD.
