.400 H&H Belted Magnum

Technical Specifications

 

Country of Origin United Kingdom
Diameter – Bore .400” (10.16mm)
Diameter – Groove .410” (10,41mm)
Introduced 2002
Pressure – Max Average 63,817 psi (440 MPa)
Regulators CIP
Groove Details 6 x .1311” (3,30mm)
Shellholder – RCBS 4
Twist – Proof Barrel 1:12” (305mm)
* Read all about this cartridge in the book African Dangerous Game Cartridges by Pierre van der Walt
Cartridge Essentials

 

Action Size Recommended Stretched length, belted magnum bolt face
Barrel Life 6,000 – 6,500 rounds
Case – Body Taper 0.68°
Case – Neck Length .6804” (17,28mm) = 165.95%
Case – Trim Length 2.838” (72,09mm)
Parent Case .375 H&H Magnum
Relative Capacity 104.0 gr water (6,753cc)
Shoulder Angle 8°00’00”

Cartridge Essentials

 

Action Size Recommended Stretched length, belted magnum bolt face
Barrel Life 6,000 – 6,500 rounds
Case – Body Taper 0.68°
Case – Neck Length .6804” (17,28mm) = 165.95%
Case – Trim Length 2.838” (72,09mm)
Parent Case .375 H&H Magnum
Relative Capacity 104.0 gr water (6,753cc)
Shoulder Angle 8°00’00”
Typical Factory Load Guidelines for Africa – Solids
Brand Name Bullet Weight Bullet Description Velocity Fps Energy Ft/Lb Trauma Potential 0% Expansion
W Romey 400-gr Woodleigh 2,375 fps 5,017 ft/lb 96.2
Typical Factory Load Guidelines for Africa – Expanders
Brand Name Bullet Weight Bullet Description Velocity Fps Energy Ft/Lb Trauma Potential 100% Expansion
W Romey 400-gr Woodleigh 2,375 fps 5,017 ft/lb 48.1
Optimum Game Bullet Optimum Application Bands (400-gr averaged)
Band Velocity Parameters Start End
Green-Band ( ≤ 2,600 fps – ≥ 2,200 fps) ± 0 yds ± 75 yds
Amber-Band ( ≤ 2,200 fps – ≥ 2,000 fps) ± 75 yds ± 175 yds
Bullet Recommendations for Africa
All species        Solids. On pachyderms use flat nose monometal solids
Game Weight Recommendation
≤ 13,000-lb ( ≤ 6000-kg)
Most Suitable African Species (assuming legality)
Pachederms     , , hippo (body shots), rhino
* Read all about these animals in the book Game Animals of the World by Chris & Tilde Stuart
Optics Guidelines
Eye Relief Critical ≥ 4.0″
Exit Pupil ≤ 5mm
Magnification: Amber-Band ≥ 1x
Objective Lens ≥ 20mm – ≤ 24 mm
Parallax Adjustability No
Reticules Bold posts. German #1, #2, #4, #9, #56
Consider illuminated dots
Consider reflex sights
Handloading Guidelines
Load Development 1.0 grain increments
Primer Any Large Rifle Magnum
Propellant Range Slower medium-burning to faster slow-burning rifle: ≥ IMR-4007 – ≤ Hodgdon H-4350
Tips Use Lee factory crimp to crimp bullets with no shoulder damage
Full length resize loads
Check feeding before
* Read all about this cartridge in the book African Dangerous Game Cartridges by Pierre van der Walt