Rifle · CIP
.400 H&H Magnum
Holland & Holland's powerful belted cartridge designed for dangerous game.
- Caliber
- 0.411″ · 10.439 mm
- Introduced
- 2003
- Case
- Belted
- Parent
- .375 H&H Magnum
- Primary use
- Hunting
- Status
- Limited
- Introduced
- 2003
- Type
- Rifle
- Origin
- United Kingdom
- Inventor
- Russell Wilkin (Holland & Holland)
- Manufacturer
- Holland & Holland
- Standard
- CIP
- Status
- Limited
- Availability
- Limited
- Case capacity
- 104 gr H₂O
- Twist (typical)
- 1:16
- Primer
- Boxer Large Rifle
- Case type
- Belted
- Max pressure
- 63,817 psi, CIP transducer
- Eff. range
- 200 yd
- Max range
- 5200 yd
- Recoil
- 60–80 ft·lb
Introduced by Holland & Holland
Ballistics
Published velocity/energy data isn't available for .400 H&H Magnum. Parent case: .375 H&H Magnum.
Performance
Dimensionscase measurements · scale drawing · size vs familiar rounds
Case dimensions — the scale drawing at the top of the page is built from these.
CIP TDCC · approximate| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 10.44 | 0.411 | · |
| Neck ⌀ | 11.20 | 0.441 | · |
| Shoulder ⌀ | 12.50 | 0.492 | · |
| Shoulder angle | 8° | — | ~ |
| Base ⌀ | 13.03 | 0.513 | · |
| Rim ⌀ | 13.51 | 0.532 | · |
| Belt ⌀ | 13.56 | 0.534 | ~ |
| Rim thickness | 1.27 | 0.050 | · |
| Neck length | 17.28 | 0.680 | ≈ |
| Case length | 72.29 | 2.846 | · |
| Overall length | 90.00 | 3.543 | · |
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 H&H Magnum is highlighted below.
Factory loads
Being verified
Advertised FPS, energy, and BC are withheld until loads clear verification.
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
necked up to .411 (Russell Wilkin)
History
Holland & Holland's powerful belted magnum developed in the early 20th century for African dangerous game. The parent case to many British magnums, the .400 H&H launched 400-grain bullets at 2,100–2,200 fps. Less common than .375 H&H but used on elephant and buffalo throughout Africa.
FAQs
- What twist rate does .400 H&H Magnum use?
- .400 H&H Magnum typically uses a 1:16 twist rate.
- What bullet diameter is .400 H&H Magnum?
- .400 H&H Magnum uses a 0.411″ (10.439 mm) diameter bullet.
- Is .400 H&H Magnum still in production?
- .400 H&H Magnum is limited; typical availability is limited.
- What is .400 H&H Magnum used for?
- .400 H&H Magnum is primarily used for hunting.
- What is .400 H&H Magnum based on?
- .400 H&H Magnum is derived from the .375 H&H Magnum case.
Sources & provenance
Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 11 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →
