Rifle · SAAMI
.223 WSSM
Winchester's super-short .22 magnum — a fat, stubby case driving .22 bullets to .22-250 velocities in a short-action platform.
- Caliber
- 0.2245″ · 5.702 mm
- Introduced
- 2003
- Case
- Rebated
- Parent
- .300 WSM
- Primary use
- Varmint, Target
- Status
- Discontinued
- Introduced
- 2003
- Type
- Rifle
- Origin
- United States
- Inventor
- Winchester
- Manufacturer
- Winchester Ammunition
- Standard
- SAAMI
- Status
- Discontinued
- Availability
- Collector
- Case capacity
- 53 gr H₂O
- Twist (typical)
- 1:10
- Primer
- Large Rifle
- Case type
- Rebated
- Max pressure
- 65,000 psi
- Eff. range
- 500 yd
- Max range
- 600 yd
- Recoil
- 8–12 ft·lb
Introduced by Winchester Ammunition
Ballistics
Published velocity/energy data isn't available for .223 WSSM — an obsolete/collector cartridge. Parent case: .300 WSM.
Performance
Dimensionscase measurements · scale drawing · size vs familiar rounds
Case dimensions — the scale drawing at the top of the page is built from these.
SAAMI · approximate| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 5.70 | 0.224 | ~ |
| Neck ⌀ | 6.91 | 0.272 | ✓ |
| Shoulder ⌀ | 13.83 | 0.544 | ✓ |
| Shoulder angle | 28° | — | ✓ |
| Base ⌀ | 14.10 | 0.555 | ✓ |
| Rim ⌀ | 13.59 | 0.535 | ✓ |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.37 | 0.054 | ✓ |
| Neck length | 6.73 | 0.265 | ≈ |
| Case length | 42.42 | 1.670 | ✓ |
| Overall length | 59.94 | 2.360 | ✓ |
Size vs familiar rounds
Drawn at true 1:1 — every case is accurate relative to the others. Absolute size depends on your screen's pixel density, so measuring one against a real ruler may be off. .223 WSSM is highlighted below.
Factory loads
Being verified
Advertised FPS, energy, and BC are withheld until loads clear verification.
Suitable powders
6 reloading powders listed for .223 WSSM, fastest to slowest. Cross-reference in the finder →
Reloading costestimate cost per round vs factory
Estimate your cost per round and how it compares to factory. Inputs are yours — nothing is stored.
Cost estimate only — not load data. Charge weight is your input; follow published manuals for safe charges.
Lineage
Connected reference
History
Introduced in 2003 as part of Winchester's WSSM family for the Browning A-Bolt Short Action. The concept — maximum case capacity in minimum length — produced extremely high velocities but also extreme barrel erosion. Winchester discontinued factory WSSM ammunition around 2018–2019. Remaining rifles and ammunition are collector items.
FAQs
- What twist rate does .223 WSSM use?
- .223 WSSM typically uses a 1:10 twist rate.
- What bullet diameter is .223 WSSM?
- .223 WSSM uses a 0.2245″ (5.702 mm) diameter bullet.
- Is .223 WSSM still in production?
- .223 WSSM is discontinued; typical availability is collector.
- What is .223 WSSM used for?
- .223 WSSM is primarily used for varmint, target.
- What is .223 WSSM based on?
- .223 WSSM is derived from the .300 WSM case.
- What are the best powders for .223 WSSM?
- Reloading powders commonly listed for .223 WSSM include N530, N135, N550, Vihtavuori N140, among 6 suitable options.
Sources & provenance
- Standard SAAMI — ANSI/SAAMI Z299 — Cartridge & Chamber Drawings archived
- Standard SAAMI — ANSI/SAAMI Z299.4-2025 — Centerfire Rifle Velocity & Pressure Data · grain_ballistics, representative_gun archived
- Manufacturer Winchester Ammunition — Rifle Ammo — 223 WSSM (Super-X X223WSS product tile) · grain_ballistics, representative_gun
Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 21 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →