Home › Browse Calibers › .240 Wby. Mag.
Common uses: Hunting, Varmint
| Type | rifle (centerfire) |
| Typical load | 100gr Weatherby Hornady spire point (legacy) |
| Muzzle velocity | 3406 fps |
| Muzzle energy | 2577 ft-lb |
| Published G1 ballistic coefficient | 0.381 |
| Case length | 63.5 mm |
| Overall length | 82.6 mm |
| SAAMI max pressure | 65000 PSI |
| Common twist rate | 1:10" |
| Range (yd) | Velocity (fps) | Energy (ft-lb) | Drop (in) |
|---|---|---|---|
| 0 | 3406 | 2575 | -1.5 |
| 100 | 3130 | 2175 | 0 |
| 200 | 2870 | 1828 | -2.1 |
| 300 | 2626 | 1531 | -8.4 |
| 400 | 2395 | 1273 | -19.7 |
| 500 | 2175 | 1050 | -37.1 |
At 1,000 yards, .240 Wby. Mag. (100gr at 3406 fps, 100 yd zero, standard conditions) has a modeled come-up of about 26.3 MOA / 7.6 MIL, retaining 1286 fps (transonic).
| Range (yd) | Velocity (fps) | State | Drop (in) | Elev (MOA) | Elev (MIL) |
|---|---|---|---|---|---|
| 300 | 2626 | Supersonic | -8.4 | 2.7 | 0.77 |
| 400 | 2395 | Supersonic | -19.7 | 4.7 | 1.37 |
| 500 | 2175 | Supersonic | -37.1 | 7.1 | 2.06 |
| 600 | 1967 | Supersonic | -61.9 | 9.9 | 2.87 |
| 700 | 1772 | Supersonic | -95.8 | 13.1 | 3.80 |
| 800 | 1592 | Supersonic | -140.7 | 16.8 | 4.89 |
| 900 | 1429 | Supersonic | -199.4 | 21.2 | 6.15 |
| 1000 | 1286 | Transonic | -275.4 | 26.3 | 7.65 |
Extended predictions beyond 500 yards are modeled from the same G1 engine — useful for initial DOPE, but outside the 500-yard manufacturer-table validation audit. Confirm with observed DOPE, especially near transonic.
A retained-energy reference only — not a shoot/don't-shoot distance. Real effective range depends on your accuracy, shot placement, bullet construction, and conditions. The ~1,000 ft-lb (deer-sized) and ~1,500 ft-lb (elk-sized) figures are commonly cited rules of thumb, not standards.
Your barrel, ammunition lot, and conditions will differ — always verify against the manufacturer's data and your own rifle.
The .240 Weatherby Magnum is a high-velocity 6mm that pushes light-to-medium bullets exceptionally fast, giving it a flat trajectory and hard-hitting performance well beyond typical .243-class ranges. It is a genuine dual-purpose round, effective on varmints and predators as well as deer, pronghorn, and similar deer-sized game. Its main practical drawbacks are the cost and limited availability of ammunition and brass, since it is a proprietary Weatherby chambering with no common substitute, and the heat and barrel wear that come with its high powder capacity. Recoil remains mild relative to its reach, which makes it pleasant to shoot despite its performance. It has always been something of a niche cartridge, admired by enthusiasts but never widely adopted, largely because standard 6mm options cover most of the same ground more affordably.
Introduced by Roy Weatherby in 1968, the .240 Weatherby Magnum was the last cartridge he personally designed. Like the rest of the Weatherby line, it uses a belted case and the company's signature double-radius shoulder, chambered to launch 6mm (.243-inch) bullets at unusually high velocity. It remains a proprietary cartridge produced only by Weatherby.
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