.30-378 Weath. Mag. Load Data & Reloading Guide

Rifle

Also known as: .30-378 Weatherby Magnum, .30-378 Weathby Mag, 7.62×74mm Weatherby

About .30-378 Weath. Mag.

The .30-378 Weatherby Magnum was introduced in 1996 by Roy Weatherby as a high-performance cartridge designed for long-range shooting and big game hunting. It was developed to combine the velocity and flat trajectory of the .378 Weatherby Magnum case with a .30 caliber bullet. This combination allows it to deliver outstanding ballistic performance while maintaining manageable recoil for experienced shooters.

The key technical characteristics of the .30-378 Weatherby Magnum include a case length of 2.625 inches and an overall length of 3.6 inches. It typically operates at pressures up to 65,000 psi, which contributes to its impressive muzzle velocities, often exceeding 3,400 feet per second with appropriate loads. Reloaders can utilize various bullet weights ranging from 150 to 220 grains, allowing for versatility in load development depending on the intended use.

In terms of ballistic performance, the .30-378 Weatherby Magnum achieves exceptional flatness in its trajectory, making it an excellent choice for long-range hunting and target shooting. Its high velocity minimizes wind drift and retains energy effectively over extended distances. This caliber is particularly popular for hunting large game such as elk and moose, where its high energy transfer upon impact is critical.

For reloaders, the .30-378 Weatherby Magnum offers the advantage of a wide range of available components, including various bullet types and powders. This flexibility enables the development of tailored loads that can optimize performance for specific situations, whether for hunting, competition, or long-range precision shooting. The ability to fine-tune loads for different bullet weights also allows reloaders to maximize accuracy and terminal performance, making this caliber a compelling option for those looking to enhance their shooting experience.

Technical Drawing

.30-378 Weath. Mag. technical drawing and load data

Technical Specifications

Maximum Pressure:63817 PSI / 4400 bar
Case Volume:133 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Safety Standard:C.I.P.
Bore Area:47.32 mm²
Barrel Diameter:0.308" / 7.8 mm
L3:2.913" / 74.0 mm
L6:3.655" / 92.8 mm

Start Calculating to Develop your own Load Data for .30-378 Weath. Mag.

Use our professional ballistics calculator to develop safe and accurate load recipes for .30-378 Weath. Mag..

Start Calculating

Standard Load Data — .30-378 Weath. Mag.

Select your desired cartridge and bullet weight below to access the corresponding load table. From there, you can choose any listed load recipe and transfer it directly into the ballistics calculator for further refinement, optimization, and precision tuning.

All
85 gr
88 gr
100 gr
110 gr
115 gr
123 gr
125 gr
168 gr
170 gr
175 gr
180 gr
200 gr
210 gr
220 gr
Prvi Partizan logo

.308 | 170gr | Prvi Partizan FSP

BC G1: 0.262
53 powders307 loads
Nosler logo

.308 | 125gr | Nosler Ballistic Tip Hunting

BC G1: 0.366
74 powders453 loads
SAKO logo

.308 | 170gr | Sako Blade

59 powders364 loads
Speer logo

.308 | 168gr | Speer MHP BTHP M

BC G1: 0.5
54 powders339 loads
Speer logo

.310 | 125gr | Speer HP TNT

BC G1: 0.341
67 powders392 loads
SAKO logo

.308 | 180gr | Sako Hammerhead

BC G1: 0.387
56 powders302 loads
Berger logo

.308 | 210gr | Berger VLD Hunting

BC G1: 0.625BC G7: 0.32
45 powders245 loads
Nosler logo

.308 | 210gr | Nosler RDF

BC G1: 0.707BC G7: 0.422
44 powders243 loads
Cutting Edge logo

.311 | 100gr | CutEdge ESP Raptor

BC G1: 0.12
82 powders535 loads
Prvi Partizan logo

.307 | 110gr | Prvi Partizan SP RN

BC G1: 0.176
70 powders463 loads
CamPro logo

.311 | 123gr | CamPro FCP

BC G1: 0.262
70 powders418 loads
Sellier & Bellot logo

.311 | 123gr | Sellier & Bellot FMJ

BC G1: 0.268
70 powders416 loads
SAKO logo

.308 | 175gr | SAKO Blade

56 powders345 loads
Swift logo

.308 | 180gr | Swift Scirocco

BC G1: 0.52
53 powders331 loads
Reichenberg logo

.308 | 200gr | Reichenberg Subsonic

BC G1: 0.2
47 powders269 loads
SAKO logo

.308 | 200gr | Sako Hammerhead

BC G1: 0.356
50 powders268 loads
Sierra logo

.308 | 200gr | Sierra GameKing

BC G1: 0.56BC G7: 0.282
48 powders265 loads
Lapua logo

.308 | 200gr | Lapua Subsonic

BC G1: 0.518BC G7: 0.235
46 powders260 loads
Berry's logo

.300 | 220gr | Berry's Spire Point

36 powders206 loads
MAKER logo

.308 | 85gr | MAKER Tipped expanding

BC G1: 0.21
95 powders573 loads
Inceptor logo

.308 | 88gr | Inceptor SRR

94 powders532 loads
Styria Arms | AERO logo

.308 | 115gr | AERO SUB,- smax:11.40

BC G1: 0.2063
78 powders501 loads
Lehigh Defense logo

.311 | 123gr | Lehigh Defense Controlled Chaos

BC G1: 0.286
76 powders482 loads
Winchester logo

.308 | 110gr | Winchester Hollow Point

BC G1: 0.18
72 powders479 loads

Frequently Asked Questions

The maximum pressure for .30-378 Weath. Mag. is 63,817 psi | 4,400 bar.

.30-378 Weath. Mag. typically uses a Large Rifle Magnum (LRM) primer.

The case capacity of .30-378 Weath. Mag. is approximately 133 grains of water (H₂O).