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Common uses: Hunting, Varmint
| Type | rifle (centerfire) |
| Typical load | 100gr Winchester Super-X Power-Point |
| Muzzle velocity | 3110 fps |
| Muzzle energy | 2148 ft-lb |
| Published G1 ballistic coefficient | 0.356 |
| Case length | 42.42 mm |
| Overall length | 60 mm |
| SAAMI max pressure | 65000 PSI |
| Range (yd) | Velocity (fps) | Energy (ft-lb) | Drop (in) |
|---|---|---|---|
| 0 | 3110 | 2147 | -1.5 |
| 100 | 2834 | 1782 | 0 |
| 200 | 2575 | 1472 | -2.8 |
| 300 | 2330 | 1206 | -11 |
| 400 | 2100 | 979 | -25.5 |
| 500 | 1882 | 786 | -48 |
At 1,000 yards, .243 WSSM (100gr at 3110 fps, 100 yd zero, standard conditions) has a modeled come-up of about 35.2 MOA / 10.2 MIL, retaining 1098 fps (subsonic).
| Range (yd) | Velocity (fps) | State | Drop (in) | Elev (MOA) | Elev (MIL) |
|---|---|---|---|---|---|
| 300 | 2330 | Supersonic | -11.0 | 3.5 | 1.02 |
| 400 | 2100 | Supersonic | -25.5 | 6.1 | 1.77 |
| 500 | 1882 | Supersonic | -48.0 | 9.2 | 2.67 |
| 600 | 1681 | Supersonic | -80.3 | 12.8 | 3.72 |
| 700 | 1497 | Supersonic | -125.0 | 17.1 | 4.96 |
| 800 | 1335 | Transonic | -185.3 | 22.1 | 6.43 |
| 900 | 1201 | Transonic | -265.0 | 28.1 | 8.18 |
| 1000 | 1098 | Subsonic | -368.9 | 35.2 | 10.25 |
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 .243 WSSM was designed to push standard 6mm bullets faster than the long-established .243 Winchester by burning a large powder charge behind a light-to-medium projectile, making it a hard-hitting choice for varmints, predators, and deer-sized game at extended range. Its flat trajectory and high velocity gave it genuine reach on prairie dogs, coyotes, and antelope. In practice the short, wide case earned a reputation for rapid throat erosion, with some shooters reporting noticeably shortened accurate barrel life, though the severity was disputed and varied with loading. Poor factory ammunition and rifle availability, combined with only a marginal ballistic edge over the far more common .243 Winchester, kept it from catching on. Today it survives mainly as a niche cartridge of interest to handloaders and collectors rather than a mainstream hunting option.
Introduced in 2003 by Winchester in partnership with Browning, the .243 WSSM was created by shortening the .300 WSM case and necking it down to 6mm. It was one of three cartridges in the short-lived Winchester Super Short Magnum family, all built around a fat, stubby case that promised magnum-class velocity in a very compact action. Both companies dropped their WSSM rifles and ammunition within a few years, and the line is now effectively obsolete with no rifles in current production.
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