Rifle · Proprietary
.500 Whisper
The .500 Whisper is a subsonic, belted bottleneck rifle cartridge by J.D.
- Caliber
- 0.51″ · 12.95 mm
- Introduced
- 1990
- Case
- Belted
- Parent
- .378 Weatherby Magnum
- Primary use
- Suppressed
- Status
- Limited
- Introduced
- 1990
- Type
- Rifle
- Origin
- United States
- Inventor
- J. D. Jones (SSK Industries)
- Manufacturer
- SSK Industries
- Standard
- Proprietary
- Status
- Limited
- Availability
- Rare
- Case capacity
- 103.8 gr H₂O
- Twist (typical)
- 1:20
- Primer
- Large Rifle Magnum
- Case type
- Belted
- Max pressure
- 63,800 psi, CIP transducer
- Eff. range
- 150 yd
- Max range
- 4050 yd
- Recoil
- 35.8–43.5 ft·lb
- Subsonic
- Capable
Ballistics
Velocity only, no drag model: no published ballistic coefficient is on file for .500 Whisper, 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
- .378 Weatherby Magnum
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.
Wikipedia · approximate| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 12.95 | 0.510 | · |
| Neck ⌀ | 13.94 | 0.549 | · |
| Shoulder ⌀ | 14.12 | 0.556 | |
| Shoulder angle | 25° | — | |
| Base ⌀ | 14.78 | 0.582 | · |
| Rim ⌀ | 14.71 | 0.579 | · |
| Belt ⌀ | 15.33 | 0.604 | |
| Rim thickness | 1.60 | 0.063 | · |
| Neck length | 6.98 | 0.275 | |
| Case length | 57.00 | 2.244 | |
| Overall length | 84.84 | 3.340 |
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. .500 Whisper is highlighted below.
Missing a dimension for .500 Whisper? 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
One of the SSK Whisper family developed in the 1990s.
FAQs
- What twist rate does .500 Whisper use?
- .500 Whisper typically uses a 1:20 twist rate.
- What bullet diameter is .500 Whisper?
- .500 Whisper uses a 0.51″ (12.95 mm) diameter bullet.
- Is .500 Whisper still in production?
- .500 Whisper is limited; typical availability is rare.
- What is .500 Whisper used for?
- .500 Whisper is primarily used for suppressed.
- What is .500 Whisper based on?
- .500 Whisper is derived from the .378 Weatherby Magnum case.
Sources & provenance
Data & sources. Specs compiled from the Lindcott Armory reference; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →
