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Zeroing at 25, 36 or 50 Yards: Where a Short Zero Really Hits at 100 to 400

A dead-on 25 yard zero is not a 100 yard zero. How far low to hit at 25 for your sight height, where 25, 36 and 50 yard zeros cross again, and why any error at 25 is four times larger at 100.

6 min readSolved with the Ballista engineUpdated October 2026

A common question on long-range forums: “Can I zero at 25 yards and be zeroed at 100?” Put the 6.5 Creedmoor from our reference set dead on at 25 yd, with the scope 1.6 in over the bore, and it hits 2.9 in high at 100 yd and crosses the line of sight again at about 250 yd. Raise the scope to 2.5 in and the same 25 yd zero is 5.6 in high at 100. A 25 yd zero is a perfectly good way to get on paper. As a 100 yd zero it’s wrong by an amount set mostly by your sight height.

At 25 yards the bullet is still climbing to the scope line

The scope sits above the bore, so the bullet starts below the line of sight and has to climb to meet it. With a 100 yd zero the bore is tilted up just enough for the bullet to cross the line of sight at 100. At 25 yd it has covered only a quarter of that climb, so it’s still well below the crosshair. That gap is the number you want: aim at a dot at 25 yd and adjust until the group lands that far below it.

The offset grows with sight height. At 25 yd the 6.5 hits 0.66 in low with a 1.5 in scope height and 1.41 in low with 2.5 in. The cartridge barely matters this close: the .308’s numbers are within 0.07 in of the 6.5’s. So the table works for most centerfire rifles, and your sight height is the input that sets it. The sight height article shows how to measure it.

A dead-on 25 yard zero is a long zero

If you skip the offset and zero dead on at 25, the bore ends up tilted more steeply. The bullet crosses the line of sight at 25, keeps climbing past it, and comes back down much farther out. The result is a long zero with a near crossing at 25.

For a hunting rifle with a tall scope, the dead-on 25 yd zero lands several inches high from 100 to 300 yd. That’s close to a point-blank zero, and some hunters choose it on purpose. The trouble starts when a shooter believes it’s a 100 yd zero and then dials elevation from a dope card built for 100. Every come-up on that card is then off by the 25 yd zero’s height at that range. The point-blank range article covers how to pick a deliberately high zero.

AR-style zeros at 36 and 50 yards

AR shooters use short zeros on purpose, because with a tall optic and a fast, light bullet a near zero also gives a useful far zero. The second crossing is the number that matters, and it depends on the load and sight height, so treat the yard pairs passed around as starting points.

With this load and a 2.6 in optic height, a 50 yd zero crosses again at about 230 yd and a 36 yd zero at about 300 yd. At 300 yd the 36 yd zero is 0.1 in high and the 50 yd zero 5.2 in low. A 25 yd zero on the same rifle stays above the line of sight until about 390 yd. Lower the optic and every far zero comes in closer. Change bullets and they move again. Confirm the far zero on paper before relying on it.

Every error at 25 is four times larger at 100

A short zero is an angle. Whatever angle you set at 25 yd, the rifle carries it to 100 yd, where the same angle covers four times as many inches. The engine confirms it: putting the 25 yd group 0.125 in off the intended spot moves the 100 yd impact by 0.50 in.

That has three practical consequences.

• Measure the group center carefully. A 1/8 in mistake on the 25 yd target is a 0.5 in mistake at 100. Shoot a group of three to five and measure its center, not the last hole.
• Clicks are tiny at 25. One 1/4 MOA click moves the impact about 0.065 in at 25 yd, about 1/16 in. Count clicks from the measured offset rather than nudging by eye.
• Sight height must be right. Say the rifle’s real sight height is 2.0 in, but you took the 25 yd offset for 1.5 in and set the group 0.66 in low. That rifle hits 1.5 in high at 100. Every long-range come-up after that inherits the same error.

So the 25 yd zero gets you to a 100 yd zero only if the offset and the measurement are both right. Confirm it at 100.

Using a short zero in Ballista

Ballista’s rifle profile takes a Sight height, with a note under it on how to measure from the center of the bore to the center of the scope. In the Zero section, Zero distance can be 25, 36 or 50 yd if that’s the zero you actually have, and “Impact above aim at zero” covers a group set deliberately high or low. The come-ups for every distance are then solved from the zero you shot, so you don’t have to convert it to 100 yd first.

A short-zero routine

1. Measure your sight height, bore center to scope center.
2. Look up how far low a 100 yd zero hits at 25 yd for that height (table above), or solve it for your load.
3. Shoot a group at 25 yd, measure its center and dial the group onto the offset point below your aiming dot.
4. Confirm at 100 yd. Expect to touch it up by a click or two.
5. If you keep a short zero on purpose, enter it in your solver as it is, and verify the far crossing on paper.