Wildcat · Wildcat · Not SAAMI standardized · Not standardizedObsolete
.220 Weatherby Rocket
Early Roy Weatherby improved .220 Swift wildcat — Weatherby's first cartridge..
- Caliber
- 0.224″ · 5.69 mm
- Introduced
- 1945
- Case
- Semi-Rimmed
- Parent
- .220 Swift
- Primary use
- Varmint
- Status
- Obsolete
- Obsolete
- Obsolete
- Introduced
- 1945
- Type
- Wildcat
- Origin
- United States
- Inventor
- Roy Weatherby
- Manufacturer
- Weatherby
- Standard
- Wildcat · Not SAAMI standardized · Not standardized
- SAAMI
- Not SAAMI standardized
- Obsolete
- Obsolete
- Status
- Obsolete
- Availability
- Collector
- Case capacity
- 55.5 gr H₂O
- Twist (typical)
- 1:14
- Primer
- Large Rifle
- Case type
- Semi-Rimmed
- Max pressure
- 38,000 psi, SAAMI transducer
- Eff. range
- 400 yd
- Max range
- 3500 yd
- Recoil
- 6.8–9.5 ft·lb
Introduced by Weatherby
Ballistics
Velocity only, no drag model: no published ballistic coefficient is on file for .220 Weatherby Rocket, so this is the shape gravity alone gives the advertised velocity. Drag would steepen it. The tool below solves real loads through their published G1 or G7 model.
Open in Ballistic Compare- Parent case
- .220 Swift
Representative trajectory — modeled from a single velocity input (no published BC for this cartridge yet).
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 ⌀ | 5.69 | 0.224 | · |
| Neck ⌀ | 6.60 | 0.260 | · |
| Shoulder ⌀ | 10.92 | 0.430 | · |
| Shoulder angle | 33° | — | · |
| Base ⌀ | 11.25 | 0.443 | ~ |
| Rim ⌀ | 11.99 | 0.472 | · |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.27 | 0.050 | ~ |
| Neck length | 5.87 | 0.231 | |
| Case length | 56.01 | 2.205 | ~ |
| Overall length | 68.07 | 2.680 | |
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. .220 Weatherby Rocket is highlighted below.
Missing a dimension for .220 Weatherby Rocket? Some case measurements aren't in a published SAAMI/CIP drawing yet. Have a factory or reamer print? Send it → — verified hard-to-find data earns a free Lindcott sticker.
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
Weatherby's first cartridge (1940s); a fire-formed/improved .220 Swift, never commercially produced (chronic throat erosion).
FAQs
- What twist rate does .220 Weatherby Rocket use?
- .220 Weatherby Rocket typically uses a 1:14 twist rate.
- What bullet diameter is .220 Weatherby Rocket?
- .220 Weatherby Rocket uses a 0.224″ (5.69 mm) diameter bullet.
- Is .220 Weatherby Rocket still in production?
- .220 Weatherby Rocket is obsolete; typical availability is collector.
- What is .220 Weatherby Rocket used for?
- .220 Weatherby Rocket is primarily used for varmint.
- What is .220 Weatherby Rocket based on?
- .220 Weatherby Rocket is derived from the .220 Swift case.
Sources & provenance
- Secondary Ballistic Studies (Nathan Foster / Terminal Ballistics Research) — .224 Weatherby Knowledge Base (covers the earlier .220 Weatherby Rocket) · velocity, bullet ⌀ archived
- Secondary Weatherby Collectors Association — Weatherby History · year archived
Data & sources. Specs compiled from the Lindcott Armory reference; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →
