MOA vs MIL: Which Rifle Scope Turret Is Right for You?

MOA and MIL are the two languages a rifle scope uses to measure adjustment and holdover. Both are angular units, both are precise, and neither is inherently more accurate. The confusion comes from mixing them up — so let's make them concrete.

What each unit actually measures

MOA (minute of angle) is 1/60th of a degree. At 100 yards it covers about 1.047 inches — near enough to "one inch at 100 yards" for a working rule. Most MOA turrets click in 1/4 MOA, so four clicks move point of impact roughly one inch at 100 yards.

MIL (milliradian) is 1/1000th of a radian. At 100 yards one mil covers about 3.6 inches (or exactly 10 cm at 100 meters). Most MIL turrets click in 0.1 MIL, so one click moves point of impact about 0.36 inch at 100 yards.

Both are angular, which is the part people skip over, and it is the key to everything else. An angle covers more ground the further out you go. One MOA is about an inch at 100 yards, two inches at 200, five at 500. One mil is 3.6 inches at 100 yards and 36 inches at 1,000. Nothing about your scope changes with distance — the same click moves the bullet a bigger distance simply because the target is further away.

This is why neither unit is "finer" in any meaningful sense. A 0.1 mil click is 0.36 inch at 100 yards and a 1/4 MOA click is about 0.26 inch, so MOA clicks are slightly smaller — but the difference is far below what the rifle, the ammunition or the shooter can resolve. Anyone telling you MOA is more precise because the clicks are smaller is measuring the wrong thing.

The rule that actually matters

Match your reticle to your turrets. A MIL reticle belongs with MIL turrets; an MOA reticle belongs with MOA turrets. When they agree, you can see a miss as "0.4 mil low," reach up and dial 0.4 mil, and be corrected — no math, no conversion. Mixing a MIL reticle with MOA turrets forces a conversion on every shot, which is exactly where field mistakes happen. This is why every scope we stock is offered in matched pairs; for example the Athlon Helos BTR GEN2 4-20x50 in MIL and the same scope in MOA.

If you take one thing from this article, take that. A mismatched scope is not broken and it is not useless, but it taxes you on every single correction, under exactly the conditions where you least want to be doing arithmetic.

Why the reticle has to be in the right focal plane too

There is a second trap behind the first. Holdover marks on a second focal plane reticle are only correct at one magnification — usually maximum. Dial the zoom down and the marks still look the same size to your eye, but the target has shrunk behind them, so a "0.4 mil" hash is no longer 0.4 mil.

On a first focal plane reticle the marks grow and shrink with the image, so they stay true at any magnification. If you intend to use your reticle for holdovers rather than just dialling, this matters as much as the unit choice. Our guide to FFP vs SFP covers it properly.

Converting, if you have to

You should not need to convert routinely, but it is useful to know the relationship: 1 mil = 3.438 MOA. For quick field maths, 1 mil is about 3.5 MOA, and 3 MOA is a bit under 1 mil.

Where this genuinely comes up is talking to a shooting partner who uses the other system, or reading a ballistic app set to the wrong unit. Both are better fixed at the source than corrected in your head.

A note on ranging

Mils became the standard in military and precision circles partly because ranging maths is tidier in them. With a target of known size, range in yards is roughly the target size in inches multiplied by 27.8, divided by the measurement in mils. The MOA version works the same way with a different constant.

In practice almost nobody ranges with a reticle any more — a laser rangefinder is faster and far more accurate. Treat reticle ranging as a backup skill rather than a reason to choose a unit.

So which should you pick?

• Choose MIL if you shoot with others who use mils, follow precision-rifle content, or want the finer 0.1-mil clicks that dominate the PRS world.
• Choose MOA if you think in inches, do most of your zeroing and holds at 100-yard increments, or are coming from a hunting background where MOA is common.

The strongest argument for mils is social: if the people you shoot with call corrections in mils, you want to be able to act on "come up point two" without translating. The strongest argument for MOA is also social, in the other direction — if everyone around you thinks in inches, so should your scope.

What if you already own a mix?

Do not panic and do not sell anything in a hurry. A mismatched scope is still a perfectly good scope — it just means you should dial rather than hold, because dialling only uses the turrets and sidesteps the reticle entirely. Set your ballistic app to the turret's unit and ignore the reticle marks for corrections.

When you next buy, standardise. Whichever you pick, commit to it across your rifles so your muscle memory transfers. For long-range work where dialing matters most, see our long-range rifle scopes, and if you are choosing a scope from scratch start with how to choose a rifle scope. For what the hash marks themselves mean, see understanding reticles.