How is bullet drop estimated without a chronograph chart?

The calculator uses a simplified point-mass drag model: it derives a retardation coefficient from the G1 ballistic coefficient, steps the bullet downrange in small time increments, and accumulates gravity drop. It is an approximation, not a substitute for verified dope, but it is close enough to pick the right hash.

What is reticle subtension?

Subtension is the angular value a reticle feature covers. A BDC hash that sits 3 MOA below centre subtends 3 MOA, which equals about 3 inches at 100 yards or 18 inches at 600 yards. Matching drop in MOA to the hash subtension tells you which mark to hold.

Why convert drop to MOA or MRAD?

Scope reticles are angular, so a drop of 24 inches at 400 yards must be converted to angle before you can match it to a hash. One MOA equals 1.047 inches at 100 yards; the tool scales that with distance and divides drop by it to get the angular holdover.

Is this safe to use for ethical hunting shots?

Treat the output as a starting point only. Atmospheric conditions, your exact load, and barrel differences all shift real impact. Always confirm holdovers on a range at known distances before taking a field shot, and keep shots within your verified envelope.

Does this account for wind or angle?

No. This tool solves vertical drop and BDC matching only. Wind drift, uphill or downhill angle, and spin drift are separate corrections you must add from a full ballistic solver or field experience.

Hunting BDC Reticle Holdover Calculator

A BDC reticle is only useful if you know which hash to hold on at a given range. This calculator models your cartridge’s drop, converts it to the same angular units as your reticle, and maps each shooting distance to the nearest hash mark so you can take the shot without dialing.

How it works

The tool runs a simplified point-mass trajectory and then matches drop to your reticle. The angular conversions used are:

1 MOA  ≈ 1.047 in per 100 yd
1 MRAD ≈ 3.6   in per 100 yd
drop (angular) = drop_inches / (unit_per_100yd × distance_yd / 100)
hash to hold   = round( drop_angular / subtension_per_hash )

Drop itself is accumulated by stepping the bullet downrange in small time slices, applying a velocity-dependent drag retardation derived from the G1 ballistic coefficient, plus constant gravity. The crosshair zero is subtracted so distances inside the zero read as zero holdover.

Example and tips

A 2,900 fps load with a 0.45 G1 BC zeroed at 200 yards drops roughly 9 inches at 300 and 26 inches at 400 yards. At 400, that is about 6.2 MOA, so on a reticle with 2 MOA per hash you would hold on the third hash. Always verify these holds on a range at true measured distances before trusting them in the field — this model ignores wind, shot angle, and your barrel’s individual velocity.