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Load data for .338-378 Weath. Mag. + 300gr Nosler Custom Competition

282 suitable loads across 54 powder(s) for cartridge .338-378 Weath. Mag. with 300gr Nosler Custom Competition bullet.

The most recommended powders for this combination are ADI AR 2218, Hodgdon H4831 and Vihtavuori N570.

.338-378 Weath. Mag. cartridge with combo bulletSeated DepthL3 = 2.910 in / 73.91 mmL6 = 3.750 in / 95.25 mmSeated Depth = .885 in / 22.48 mm

Based on C.I.P., the max. allowed case length is 2.913 in / 73.99 mm, the max. cartridge length is 3.763 in / 95.58 mm, and the max. allowed pressure is 63,817 PSI / 4,400 bar.

300gr Nosler Custom Competition bullet image

Load Specifications

ImperialMetric
Bullet:.338 | 300gr | Custom Competition
Cartridge:.338-378 Weath. Mag. load data
Case Length (L3):2.910" | 73.9 mm
Cartridge Length (COL/L6):•••
Seated Depth:0.885" | 22.5 mm
Case Capacity:137 gow | 8.88 cm³
Primer Size:Large Rifle Magnum (LRM)
Max. Pressure (C.I.P.):63,817 psi | 4,400 bar
Barrel Length:26.0" | 660 mm
Min. Twist Rate:1:12.0

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Community Loads for .338-378 Weath. Mag. + 300gr Nosler Custom Competition

Real loads for this combination shared by our community. Charge weights are only fully visible with an active Pro licence.

PowderCharge (gr)C.O.L.Barrel LengthVelocity (fps)Pressure (psi)

Charge weights beyond the first rows and all pressure values are only visible with an active Pro licence.