Load Specifications
Load data in caliber .378 Weath. Mag. with .375 | 300gr | Norma ORYX bullet and 78 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Vihtavuori N560, Accurate MAGPRO and Ramshot Grand.
Important Notice: DO NOT go below Minimum Charge or above Maximum Charge. Since we have no control over the equipment and components used, any responsibility and liability for the results achieved is rejected.
Only powders/loads that match the current filter criteria are displayed: max pressure of a load ≤ 90% of max. standardized pressure, fill rate ≥ 80% and propellant combustion ≥ 95%. Use the sliders above the tables to adjust these thresholds.
Charge: Powder weight in grains. Start with the minimum load and work up carefully.
FR (Fill Rate): Case fill as a percentage. Values above 100% mean compressed loads.
MaxP / %: Maximum chamber pressure in bar and as a percentage of the standardized maximum for this caliber.
V(0): Muzzle velocity in feet per second (fps) at the standardized barrel length.
z (Powder Burn): Estimated propellant combustion percentage at bullet exit.
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Max Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 96% | 56,173 psi | 88% | 2766 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 54,085 psi | 85% | 2746 fps | 100% |
| Accurate MAGPRO | <<locked>> | 94% | 54,650 psi | 86% | 2864 fps | 98.3% |
| ADI AR 2208 | <<locked>> | 82% | 55,579 psi | 87% | 2703 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 54,795 psi | 86% | 2802 fps | 99.6% |
| ADI AR 2213 | <<locked>> | 96% | 56,159 psi | 88% | 2861 fps | 99.2% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 47,021 psi | 74% | 2707 fps | 98% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 41,756 psi | 65% | 2674 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 56,884 psi | 89% | 2723 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 88% | 55,027 psi | 86% | 2799 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 56,202 psi | 88% | 2812 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 54,418 psi | 85% | 2792 fps | 99.6% |
| Alliant Reloder-22 | <<locked>> | 96% | 55,985 psi | 88% | 2858 fps | 99.8% |
| Alliant Reloder-23 | <<locked>> | 98% | 57,029 psi | 89% | 2822 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 52,663 psi | 83% | 2835 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 94% | 57,537 psi | 90% | 2917 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 54,592 psi | 86% | 2769 fps | 96.5% |
| Bofors RP15 | <<locked>> | 98% | 54,984 psi | 86% | 2841 fps | 99.7% |
| Bofors RP30ᴾ | <<locked>> | 100% | 48,660 psi | 76% | 2776 fps | 98.7% |
| Bofors RP5 | <<locked>> | 96% | 55,985 psi | 88% | 2858 fps | 99.8% |
| Bofors RP7 | <<locked>> | 86% | 56,898 psi | 89% | 2746 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 51,634 psi | 81% | 2789 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 86% | 55,854 psi | 88% | 2799 fps | 100% |
| Hodgdon H4350 | <<locked>> | 84% | 55,100 psi | 86% | 2756 fps | 99.7% |
| Hodgdon H4831 | <<locked>> | 94% | 56,159 psi | 88% | 2802 fps | 98.7% |
| Hodgdon H4831 SC | <<locked>> | 94% | 54,998 psi | 86% | 2782 fps | 98.6% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 55,288 psi | 87% | 2720 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 51,561 psi | 81% | 2900 fps | 99.9% |
| Hodgdon Superformance | <<locked>> | 86% | 56,202 psi | 88% | 2838 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,028 psi | 58% | 1699 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 54,766 psi | 86% | 2733 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 84% | 54,868 psi | 86% | 2717 fps | 100% |
| IMR 4831 | <<locked>> | 88% | 54,534 psi | 85% | 2736 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 57,246 psi | 90% | 2782 fps | 98.9% |
| IMR 7828 SSC | <<locked>> | 98% | 57,638 psi | 90% | 2894 fps | 99.4% |
| Lovex S065 | <<locked>> | 86% | 55,448 psi | 87% | 2717 fps | 100% |
| Lovex S070 | <<locked>> | 88% | 56,971 psi | 89% | 2762 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 53,534 psi | 84% | 2730 fps | 100% |
| Norma 204 | <<locked>> | 88% | 55,535 psi | 87% | 2789 fps | 99.6% |
| Norma 217ᴾ | <<locked>> | 100% | 37,289 psi | 58% | 2598 fps | 97.9% |
| Norma MRP | <<locked>> | 94% | 55,695 psi | 87% | 2877 fps | 100% |
| Norma URP | <<locked>> | 88% | 56,246 psi | 88% | 2779 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 54,404 psi | 85% | 2858 fps | 99.3% |
| Ramshot Hunter | <<locked>> | 88% | 54,969 psi | 86% | 2785 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 56,565 psi | 89% | 2851 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,811 psi | 59% | 1742 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 57,551 psi | 90% | 2753 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 55,593 psi | 87% | 2795 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 54,041 psi | 85% | 2769 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 56,014 psi | 88% | 2851 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 51,909 psi | 81% | 2897 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 46,847 psi | 73% | 2782 fps | 97.1% |
| Rottweil R 903 | <<locked>> | 82% | 54,592 psi | 86% | 2694 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 56,115 psi | 88% | 2769 fps | 99.1% |
| Rottweil R 905 | <<locked>> | 94% | 57,406 psi | 90% | 2831 fps | 99.8% |
| Rottweil R 907 | <<locked>> | 86% | 56,898 psi | 89% | 2746 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 86% | 55,448 psi | 87% | 2717 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 56,971 psi | 89% | 2762 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 56,043 psi | 88% | 2753 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 54,607 psi | 86% | 2566 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 54,592 psi | 86% | 2671 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 57,014 psi | 89% | 2828 fps | 99.8% |
| Somchem S355 | <<locked>> | 82% | 54,317 psi | 85% | 2687 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 57,696 psi | 90% | 2766 fps | 98.8% |
| Somchem S365 | <<locked>> | 90% | 56,405 psi | 88% | 2779 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 54,346 psi | 85% | 2753 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 84% | 55,506 psi | 87% | 2661 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 54,476 psi | 85% | 2720 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 57,334 psi | 90% | 2782 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 88% | 57,276 psi | 90% | 2779 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 55,883 psi | 88% | 2799 fps | 100% |
| Vihtavuori N560 | <<locked>> | 94% | 55,637 psi | 87% | 2874 fps | 98.9% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 55,259 psi | 87% | 2854 fps | 99% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 48,167 psi | 75% | 2789 fps | 96.8% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 57,638 psi | 90% | 2730 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 55,999 psi | 88% | 2799 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 98% | 54,230 psi | 85% | 2907 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 54,172 psi | 85% | 2749 fps | 99.5% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 32,909 psi | 52% | 2356 fps | 97.6% |
| Accurate 4350 | <<locked>> | 80% | 44,251 psi | 69% | 2592 fps | 100% |
| Accurate MAGPRO | 101.4 gr | 86% | 41,205 psi | 65% | 2621 fps | 95.1% |
| ADI AR 2208 | <<locked>> | 80% | 52,344 psi | 82% | 2657 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 36,999 psi | 58% | 2474 fps | 96.2% |
| ADI AR 2213 | <<locked>> | 86% | 40,248 psi | 63% | 2575 fps | 95.9% |
| ADI AR 2217 | <<locked>> | 94% | 38,580 psi | 60% | 2536 fps | 95.6% |
| ADI AR 2225 | <<locked>> | 90% | 30,371 psi | 48% | 2385 fps | 95.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 53,447 psi | 84% | 2677 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 42,453 psi | 67% | 2598 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 48,776 psi | 76% | 2707 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 36,985 psi | 58% | 2470 fps | 96.3% |
| Alliant Reloder-22 | <<locked>> | 82% | 35,099 psi | 55% | 2470 fps | 95.8% |
| Alliant Reloder-23 | <<locked>> | 80% | 31,531 psi | 49% | 2382 fps | 99.7% |
| Alliant Reloder-25 | <<locked>> | 80% | 27,630 psi | 43% | 2293 fps | 96% |
| Alliant Reloder-26 | <<locked>> | 80% | 34,200 psi | 54% | 2510 fps | 99.2% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 51,416 psi | 81% | 2717 fps | 95.7% |
| Bofors RP15 | <<locked>> | 84% | 34,882 psi | 55% | 2464 fps | 95.6% |
| Bofors RP30 | <<locked>> | 92% | 37,144 psi | 58% | 2549 fps | 95.8% |
| Bofors RP5 | <<locked>> | 82% | 35,099 psi | 55% | 2470 fps | 95.8% |
| Bofors RP7 | <<locked>> | 80% | 47,108 psi | 74% | 2592 fps | 99.3% |
| Hodgdon H1000 | <<locked>> | 90% | 36,883 psi | 58% | 2500 fps | 95.6% |
| Hodgdon H414 | <<locked>> | 80% | 45,890 psi | 72% | 2638 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 80% | 48,472 psi | 76% | 2651 fps | 99.1% |
| Hodgdon H4831 | <<locked>> | 84% | 40,132 psi | 63% | 2523 fps | 95.2% |
| Hodgdon H4831 SC | <<locked>> | 84% | 39,421 psi | 62% | 2507 fps | 95% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 40,045 psi | 63% | 2487 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 32,634 psi | 51% | 2477 fps | 95.1% |
| Hodgdon Superformance | <<locked>> | 80% | 45,092 psi | 71% | 2661 fps | 99.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,717 psi | 43% | 1519 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 42,670 psi | 67% | 2530 fps | 98.7% |
| IMR 4451 Enduron | <<locked>> | 80% | 48,501 psi | 76% | 2615 fps | 99.6% |
| IMR 4831 | <<locked>> | 80% | 42,148 psi | 66% | 2539 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 82% | 39,436 psi | 62% | 2470 fps | 95.2% |
| IMR 7828 SSC | <<locked>> | 86% | 38,566 psi | 60% | 2549 fps | 95.4% |
| Lovex S065 | <<locked>> | 80% | 46,050 psi | 72% | 2569 fps | 99.9% |
| Lovex S070 | <<locked>> | 80% | 44,396 psi | 70% | 2562 fps | 99.4% |
| Lovex S071 | <<locked>> | 80% | 28,355 psi | 44% | 2238 fps | 95.8% |
| Norma 204 | <<locked>> | 80% | 42,525 psi | 67% | 2566 fps | 97.7% |
| Norma 217 | <<locked>> | 94% | 30,705 psi | 48% | 2428 fps | 95.1% |
| Norma MRP | <<locked>> | 80% | 34,156 psi | 54% | 2477 fps | 97% |
| Norma URP | <<locked>> | 80% | 43,468 psi | 68% | 2579 fps | 100% |
| Ramshot Grand | 98.7 gr | 86% | 38,130 psi | 60% | 2556 fps | 95.7% |
| Ramshot Hunter | <<locked>> | 80% | 42,308 psi | 66% | 2579 fps | 99.5% |
| Ramshot Magnum | <<locked>> | 84% | 31,691 psi | 50% | 2385 fps | 95.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,355 psi | 44% | 1555 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 53,969 psi | 85% | 2703 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 51,750 psi | 81% | 2746 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 44,005 psi | 69% | 2612 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 42,308 psi | 66% | 2628 fps | 99.9% |
| ReloadSwiss RS 76 | <<locked>> | 86% | 31,691 psi | 50% | 2454 fps | 96% |
| ReloadSwiss RS 80 | <<locked>> | 96% | 40,451 psi | 63% | 2654 fps | 95.1% |
| Rottweil R 903 | <<locked>> | 80% | 51,198 psi | 80% | 2644 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 38,348 psi | 60% | 2454 fps | 95.5% |
| Rottweil R 905 | <<locked>> | 80% | 36,216 psi | 57% | 2454 fps | 96.3% |
| Rottweil R 907 | <<locked>> | 80% | 47,108 psi | 74% | 2592 fps | 99.3% |
| Shooters World Long Rifle | <<locked>> | 80% | 46,050 psi | 72% | 2569 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 80% | 44,396 psi | 70% | 2562 fps | 99.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 52,504 psi | 82% | 2700 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 51,387 psi | 81% | 2526 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 45,165 psi | 71% | 2520 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 35,897 psi | 56% | 2448 fps | 96.1% |
| Somchem S355 | <<locked>> | 80% | 51,039 psi | 80% | 2641 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 41,568 psi | 65% | 2497 fps | 95.6% |
| Somchem S365 | <<locked>> | 80% | 40,364 psi | 63% | 2536 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 36,782 psi | 58% | 2441 fps | 97.3% |
| Vihtavuori N150 | <<locked>> | 80% | 48,849 psi | 77% | 2569 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 44,918 psi | 70% | 2572 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 31,850 psi | 50% | 2320 fps | 95.1% |
| Vihtavuori N550 | <<locked>> | 80% | 44,237 psi | 69% | 2579 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 35,360 psi | 55% | 2451 fps | 99.7% |
| Vihtavuori N560 | 97.3 gr | 84% | 39,595 psi | 62% | 2582 fps | 95.3% |
| Vihtavuori N565 | <<locked>> | 90% | 39,421 psi | 62% | 2572 fps | 95.6% |
| Vihtavuori N568 | <<locked>> | 98% | 44,962 psi | 70% | 2730 fps | 95.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 43,758 psi | 69% | 2536 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 46,021 psi | 72% | 2641 fps | 99.5% |
| Winchester StaBALL HD | <<locked>> | 80% | 28,007 psi | 44% | 2398 fps | 99.9% |
| Winchester Supreme 780 | <<locked>> | 80% | 33,518 psi | 53% | 2365 fps | 95% |
Recommended = one of the top powders for this cartridge and bullet combination.
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 78 powders for .378 Weath. Mag. loaded with the .375 | 300gr | Norma ORYX. Alliant Reloder-26 delivers the highest muzzle velocity at 2,917 fps; across all powders the maximum-charge window runs from 1,699 fps to 2,917 fps. ADI AR 2217 gives the best case fill at 100 %, and 78 of the 78 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 300.0 gr projectile in 0.375" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2225, Alliant Reloder-25 reach 100 % fill or more at maximum charge, so these are compressed loads: they need a long drop tube to seat cleanly and react sensitively to the case capacity of your own brass lot. Vihtavuori N560, Accurate MAGPRO, Ramshot Grand rank at the top here: for .378 Weath. Mag. with the .375 | 300gr | Norma ORYX they combine a high case fill with complete burn and sit in the upper velocity band. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.