Wildcat · Wildcat · Not SAAMI standardized · Not standardizedObsolete
.400 Taylor Magnum
Intermediate development cartridge between the .505 Gibbs and the .408 Cheyenne Tactical — a modified/necked-down .505 Gibbs..
- Caliber
- 0.3413″ · 8.67 mm
- Introduced
- 1911
- Case
- Rimless
- Parent
- .505 Gibbs
- Primary use
- Hunting
- Status
- Obsolete
- Obsolete
- Obsolete
- Introduced
- 1911
- Type
- Wildcat
- Origin
- United States
- Inventor
- Unknown / wildcat
- Manufacturer
- Handloaded only (wildcat; no factory ammunition)
- Standard
- Wildcat · Not SAAMI standardized · Not standardized
- SAAMI
- Not SAAMI standardized
- Obsolete
- Obsolete
- Status
- Obsolete
- Availability
- Collector
- Case capacity
- 127.7 gr H₂O
- Twist (typical)
- 1:10
- Primer
- Large Rifle Magnum
- Case type
- Rimless
- Max pressure
- 39,000 psi, CIP transducer
- Eff. range
- 600 yd
- Max range
- 4825 yd
- Recoil
- 28.1–40.1 ft·lb
Ballistics
Velocity only, no drag model: no published ballistic coefficient is on file for .400 Taylor Magnum, 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
- .505 Gibbs
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 ⌀ | 8.67 | 0.341 | |
| Neck ⌀ | 9.53 | 0.375 | ~ |
| Shoulder ⌀ | 15.41 | 0.607 | |
| Shoulder angle | 37.6° | — | |
| Base ⌀ | 16.26 | 0.640 | |
| Rim ⌀ | 16.26 | 0.640 | |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.65 | 0.065 | |
| Neck length | 8.95 | 0.352 | |
| Case length | 63.98 | 2.519 | |
| Overall length | 86.22 | 3.394 | |
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. .400 Taylor Magnum is highlighted below.
Missing a dimension for .400 Taylor Magnum? 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
The documented intermediate step in the .408 CheyTac lineage; explains why the .408 CheyTac is not a one-step neck-down of the .505 Gibbs.
FAQs
- What twist rate does .400 Taylor Magnum use?
- .400 Taylor Magnum typically uses a 1:10 twist rate.
- What bullet diameter is .400 Taylor Magnum?
- .400 Taylor Magnum uses a 0.3413″ (8.67 mm) diameter bullet.
- Is .400 Taylor Magnum still in production?
- .400 Taylor Magnum is obsolete; typical availability is collector.
- What is .400 Taylor Magnum used for?
- .400 Taylor Magnum is primarily used for hunting.
- What is .400 Taylor Magnum based on?
- .400 Taylor Magnum is derived from the .505 Gibbs 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 →
