How To Sight In Your Rifle Optic (Red Dots & Scopes)

Why zeroing matters and choosing a zero distance

The discussion opens with an overview of why properly zeroing a rifle optic is essential. A rifle round leaves the barrel at roughly 2,500 feet per second or more, so the optic must be aligned to place shots precisely where intended. The hosts note that there are several common zero distances, including 50 yards, 36 meters, and 100 yards, each with its own use case. Previous content has compared these options, but this segment focuses on using a 50-yard zero. They explain that the same principles apply whether the optic is a red dot or a magnified scope, and that the shooter’s preferred zero distance ultimately depends on personal needs and intended application.

Using a 25-yard target for 50- and 100-yard zeros

The hosts introduce a T.REX Arms zeroing target designed for shooters limited to 25-yard indoor ranges. This target allows a shooter to establish either a 50-yard or 100-yard zero while only shooting at 25 yards. The main box on the target is used as the point of aim, and the resulting point of impact is compared to printed reference boxes that correspond to the desired zero distance. Once shots land in the appropriate box, the zero is effectively set. A larger box on the target can later be used at 50 or 100 yards to confirm and fine-tune the zero. The target also includes guidance for different click values, such as half-MOA and full-MOA adjustments, to simplify the process.

Rifles, optics, and zero preferences

Two rifles are used to demonstrate the process. One is an IWI rifle with a 16-inch, piston-driven system, described as the manufacturer’s take on the HK416 pattern, equipped with a red dot sight. The other is a Smith & Wesson M&P15 Sport III outfitted with an LPVO (low-power variable optic). The hosts emphasize that the choice of zero distance is up to the shooter, mentioning 50 yards, 100 yards, and the 36-yard zero often favored by Marines. For red dots, one host prefers a 50-yard zero because the math and holds are straightforward. For LPVOs, a 100-yard zero is usually recommended so that the reticle’s BDC (bullet drop compensator) marks line up correctly. They stress the importance of reading the optic’s manual to understand preferred zero distance and click values, whether in MOA or mils.

Zeroing the red dot at 25 yards

The red dot is zeroed first using the 25-yard T.REX Arms target to achieve a 50-yard zero. Initial shots land significantly low, indicating that substantial elevation adjustment is needed. The optic uses half-click adjustments, so the shooter calculates roughly 26 clicks up and 6 clicks left based on the target’s printed guidance. After making these changes and firing another group, the impacts improve but are still not centered, partly due to confusion over which direction to turn the turrets, since some optics use clockwise and others counterclockwise adjustments. Additional corrections of roughly 18 to 22 clicks are made to bring the group into the 50-yard reference box. The final group places two shots solidly in the 50-yard box, with one called flyer, confirming a usable 50-yard zero from the 25-yard line.

Zeroing the LPVO and using mil-based math

Next, the LPVO on the Smith & Wesson M&P15 Sport III is zeroed. The optic is set to maximum magnification to obtain a true zero for the BDC marks, and the 25-yard target’s 100-yard box is used. The first group prints high, showing the rifle is set for a longer distance than intended. This scope adjusts in mils, with 0.2 mil per click. The host uses the target’s grid to measure the offset: at 25 yards, one printed line equals 0.3 mils. By counting 10.5 lines of vertical error, the shooter calculates approximately 3.15 to 3.3 mils of correction, translating to about 16 to 17 clicks down at 0.2 mil per click. After dialing 17 clicks of elevation, another three-shot group is fired, and the impacts move into an acceptable zone, demonstrating how basic math and the target’s grid simplify mil-based adjustments.

Confirming the zero at 100 yards and ammo considerations

With the LPVO roughly zeroed at 25 yards for a 100-yard point of impact, the shooter moves to 100 yards for confirmation. Point of aim and point of impact align on the target, though the group is not especially tight. The hosts attribute some of this to the use of standard Winchester White Box ammunition rather than match or duty loads. They recommend zeroing with the same ammunition intended for serious use, such as 77-grain loads, which typically offer better ballistic coefficients and more consistent performance. Despite the basic ammo, the resulting grouping is considered a solid combat zero, suitable for practical applications. The segment underscores that confirmation at actual distance is important, even when an initial zero is established at 25 yards.

Final thoughts on zeroing methods and adjustments

The video concludes by reiterating that zeroing a rifle is straightforward but must be done carefully to ensure accuracy. Shooters are encouraged to work within their constraints, whether limited to 25 yards indoors or able to access 50- or 100-yard ranges. The hosts acknowledge that some viewers may prefer specific loads, such as 77-grain ammunition, but emphasize using whatever is available while striving to be competent with existing tools. After establishing a basic zero, shooters can always return to the range to refine adjustments and tighten groups. The hosts invite discussion on preferred combat zeros, asking whether viewers favor 50 yards, 25 yards, 36 meters, or a strict 100-yard zero, and they stress the importance of ongoing training and periodic confirmation of the rifle’s zero.