Is a 25-Yard Zero Dead-On at 100 Yards?

by
posted on June 10, 2011
bs_2015_fs.jpg (4)

The Myth: A 25-yard zero puts you “dead-on” at 100 yards. I’ve listened to some pretty amazing ballistic theories over the years but this one is probably the most common. The theory is that, with common big game cartridges, a “zero” at 25 yards will correlate to a second “zero” at 100 yards.

The Ballistic Background: First we have to understand the concept of zero. Because a rifle’s sights are not inside the bore and a bullet’s flight path is subject to gravity, we must align our sight to intersect with the bullet’s path at a given distance. Generally, we consider the rifle’s “zero” to be the point at which the bullet’s path intersects the line of sight for the second time. In other words, if the bullet strikes the line of sight at 25 yards and then rises relative to the line of sight before falling and intersecting the line of sight again at 100 yards, we have a 100 yard zero.

Let’s look at a few common examples:

.30-06 Federal Premium 165gr. Nosler Partition 2830 fps (Factory)
25 yard zero=2.77 inches high at 100 yards

.270 WCF Winchester Silvertip 130gr. 3060 fps (Factory)
25 yard zero=3.0 inches high at 100 yards

.243 Winchester 100gr Hornady Interlock 2960 fps (Factory)
25 yard zero=2.9 inches high at 100 yards

Fact is,most common big game loads would be about 3 inches high at 100 yards. For hunting purposes it may be "close enough," but it's not "dead on" for most calibers.

The Conclusion: A 25-yard zero will put your bullet around 2.5 to 3 inches high at 100 yards depending on caliber, but it's not "dead on."

Latest

MAIN1875 Outlaw
MAIN1875 Outlaw

Taylor’s & Company Introduces 1875 Outlaw Revolver in 9mm

Taylor’s & Company has partnered with Uberti to create the 1875 Outlaw 9mm Revolver.

New for 2023: Primary Arms Optics SLx and GLx

Primary Arms Optics has released its inaugural pairs of binoculars: the SLx 10x42mm and GLx 10x42mm binoculars.

First Look: XS Sights Ghost Ring Sights for Henry Big Boy Carbines

XS Sights is offering its Ghost Ring sight sets for Henry Big Boy Carbine lever-action rifles chambered in .357 Magnum and .44 Magnum.

New for 2023: GPO Spectra 4.5-27x50i SFP

The German Precision Optics (GPO) Spectra 4.5-27x50i SFP is built for those who hunt game in environments where shooting at extended ranges is often required.

#SundayGunday: Davidson’s Pietta 1873 Great Western II

Get a closer look at the Davidson’s Pietta 1873 Great Western II, the latest addition to our #SundayGunday series.

Recipe: Fettucine with Ricotta and Venison Sauce

Contributor Brad Fenson gives his readers a hearty pasta sauce recipe to help round out the cold winter months.

Interests



Get the best of American Hunter delivered to your inbox.