Guides · Field practice

Leading Moving Targets: Lead in MIL and MOA from 200 to 600 Yards

Leads for a 3 mph walking animal and a 5 mph steel mover from 200 to 600 yards, in inches, MIL and MOA, and why the lead in angle grows far slower than time of flight.

5 min readSolved with the Ballista engineUpdated October 2026

A deer walking at 3 mph crosses 52.8 inches every second. At 600 yards a 6.5 Creedmoor bullet takes 0.79 seconds to arrive, 3.4 times as long as at 200 yards. The lead in inches grows by that same factor. The lead in mils grows by only 12%: from 1.71 mil at 200 yd to 1.93 mil at 600. That small growth is what makes leading a mover workable with one number per speed.

Lead is speed times time of flight

The bullet lands where the target will be, so you aim where it will be. For a target crossing at right angles to the line of fire:

lead = target speed × time of flight

One mile per hour is 17.6 inches per second. That makes the inch figure easy, and the table turns it into reticle units with the range.

At 300 yd the walking animal needs 19 in of lead with the 6.5, more than twice the width of an 8-inch vital zone. A center hold on a walking animal at that distance misses behind it. Most of the time the better answer is to stop the animal before the shot. When you can’t, the lead has to be in the hold.

Why the angle barely grows

Divide the lead by the range and the range cancels against the time of flight:

lead angle = target speed × time of flight ÷ range = target speed ÷ average bullet speed

Time of flight grows with range, but so does the distance the lead is measured at. What’s left is the bullet’s average speed over the flight. For the 6.5 that average is 2,568 fps over 200 yd and 2,286 fps over 600 yd. The bullet slows down, so the angle grows, but only as fast as the average speed drops.

A bullet that kept its muzzle velocity would need the same lead angle at every distance. Drag is the only thing that makes the lead in mils grow at all. That’s why the .308, with its lower ballistic coefficient, sees more growth than the 6.5, and why the growth speeds up at long range where both bullets have slowed.

One number per mph

Because the angle changes slowly, a single lead per mph works across a useful span. Take the 6.5’s 400 yd figure, 0.60 mil per mph, and use it from 200 to 600 yd for the 3 mph walker. The worst error is 2.4 in at 600 yd, inside the 4 inches from center to edge of an 8-inch vital zone. For the .308 the same idea gives 0.66 mil per mph at 400 yd.

On a steel mover you can time the target over a measured length of track to get its speed. Multiply the per-mph lead by the speed and hold it on the stadia in front of the target. At 5 mph and 500 yd the 6.5 holds 3.1 mil.

Things that change the lead

Angle of travel. Only the crossing part of the speed counts. A target walking at 45° to your line of fire crosses at 0.71 times its speed; at 30° it’s 0.5. A target walking straight toward or away from you needs no lead at all, only the right range.

Wind. Lead and wind holds add or cancel. At 400 yd a 10 mph full-value wind from 3 o’clock needs 0.63 mil right for the 6.5. If the 3 mph walker is moving right, the two add to 2.45 mil. Moving left, the wind takes part of it back: 1.18 mil. Work them out separately, then combine. The wind drift article covers the wind hold.

Your own delay. Every tenth of a second between deciding and the bullet leaving lets a 3 mph target cover 5.3 in. A smooth swing that keeps moving through the shot avoids most of it. Stopping the rifle as you press the trigger adds it back.

Elevation. The lead doesn’t change the elevation, but you have to hold both at once. Dial the elevation and hold the lead on the horizontal stadia. The reticle holds article shows how to read the grid, and why a second focal plane reticle must be at its true power when you do.

Two ways to apply it

• Tracking: swing with the target, holding the lead on the reticle, and press the shot while the rifle keeps moving. It handles speed changes, but it needs a steady swing.
• Trapping: hold the lead ahead of the target’s path, keep the rifle still, and fire as the target reaches the hold. It’s steadier from a rest, but it depends on the target keeping its speed.

A short routine

1. Range the target. Estimate its speed and how much of it is crossing your line of fire.
2. Look up the lead per mph for that range in MIL or MOA and multiply by the crossing speed.
3. Add or subtract the wind hold depending on which way the target moves.
4. Dial elevation and hold the combined lead and wind on the horizontal stadia. If you’re tracking, keep the swing going through the shot.
5. On game, if the lead is larger than the vital zone and you can stop the animal, stop it first.