Load Specifications
Load data in caliber .378 Weath. Mag. with .375 | 301gr | RWS UNI Classic bullet and 80 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 Accurate High Country.
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.
A valid access license is required to use the Personalized Load Calculator.
You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 96% | 56,304 psi | 88% | 2766 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 54,259 psi | 85% | 2746 fps | 100% |
| Accurate High Country | <<locked>> | 92% | 53,925 psi | 85% | 2861 fps | 99.2% |
| Accurate MAGPRO | <<locked>> | 94% | 54,839 psi | 86% | 2864 fps | 98.4% |
| ADI AR 2208 | <<locked>> | 82% | 55,666 psi | 87% | 2703 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 54,911 psi | 86% | 2802 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 96% | 56,333 psi | 88% | 2861 fps | 99.3% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 47,123 psi | 74% | 2707 fps | 98.2% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 41,858 psi | 66% | 2674 fps | 99.5% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 55,216 psi | 87% | 2799 fps | 99.7% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 55,216 psi | 87% | 2799 fps | 99.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 56,985 psi | 89% | 2723 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 88% | 55,143 psi | 86% | 2799 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 56,333 psi | 88% | 2812 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 54,520 psi | 85% | 2792 fps | 99.6% |
| Alliant Reloder-22 | <<locked>> | 96% | 56,115 psi | 88% | 2858 fps | 99.8% |
| Alliant Reloder-23 | <<locked>> | 98% | 57,203 psi | 90% | 2822 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 52,794 psi | 83% | 2835 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 94% | 57,696 psi | 90% | 2917 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 54,679 psi | 86% | 2769 fps | 96.6% |
| Bofors RP15 | <<locked>> | 98% | 55,143 psi | 86% | 2841 fps | 99.7% |
| Bofors RP30ᴾ | <<locked>> | 100% | 48,791 psi | 76% | 2779 fps | 98.8% |
| Bofors RP5 | <<locked>> | 96% | 56,115 psi | 88% | 2858 fps | 99.8% |
| Bofors RP7 | <<locked>> | 86% | 56,985 psi | 89% | 2746 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 51,953 psi | 81% | 2792 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 86% | 55,970 psi | 88% | 2799 fps | 100% |
| Hodgdon H4350 | <<locked>> | 84% | 55,201 psi | 87% | 2756 fps | 99.8% |
| Hodgdon H4831 | <<locked>> | 94% | 56,304 psi | 88% | 2802 fps | 98.8% |
| Hodgdon H4831 SC | <<locked>> | 94% | 55,317 psi | 87% | 2789 fps | 98.7% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 55,434 psi | 87% | 2720 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 51,750 psi | 81% | 2900 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 56,333 psi | 88% | 2838 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,028 psi | 58% | 1699 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 54,868 psi | 86% | 2733 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 84% | 54,955 psi | 86% | 2717 fps | 100% |
| IMR 4831 | <<locked>> | 88% | 54,636 psi | 86% | 2736 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 57,551 psi | 90% | 2785 fps | 99% |
| IMR 7828 SSC | <<locked>> | 96% | 54,056 psi | 85% | 2841 fps | 99.1% |
| Lovex S065 | <<locked>> | 86% | 55,579 psi | 87% | 2717 fps | 100% |
| Lovex S070 | <<locked>> | 88% | 57,072 psi | 89% | 2762 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 53,650 psi | 84% | 2730 fps | 100% |
| Norma 204 | <<locked>> | 88% | 55,680 psi | 87% | 2789 fps | 99.6% |
| Norma 217ᴾ | <<locked>> | 100% | 37,420 psi | 59% | 2602 fps | 98% |
| Norma MRP | <<locked>> | 94% | 56,014 psi | 88% | 2881 fps | 100% |
| Norma URP | <<locked>> | 88% | 56,362 psi | 88% | 2779 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 54,563 psi | 86% | 2858 fps | 99.4% |
| Ramshot Hunter | <<locked>> | 88% | 55,085 psi | 86% | 2789 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 56,782 psi | 89% | 2851 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,811 psi | 59% | 1739 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 55,883 psi | 88% | 2799 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 54,215 psi | 85% | 2769 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 56,144 psi | 88% | 2851 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 52,040 psi | 82% | 2897 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 46,978 psi | 74% | 2785 fps | 97.2% |
| Rottweil R 903 | <<locked>> | 82% | 54,723 psi | 86% | 2694 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 56,391 psi | 88% | 2772 fps | 99.2% |
| Rottweil R 905 | <<locked>> | 94% | 57,595 psi | 90% | 2835 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 86% | 56,985 psi | 89% | 2746 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 86% | 55,579 psi | 87% | 2717 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 57,072 psi | 89% | 2762 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 56,144 psi | 88% | 2749 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 54,882 psi | 86% | 2569 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 54,839 psi | 86% | 2671 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 57,130 psi | 90% | 2828 fps | 99.8% |
| Somchem S355 | <<locked>> | 82% | 54,447 psi | 85% | 2687 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 54,259 psi | 85% | 2713 fps | 98.4% |
| Somchem S365 | <<locked>> | 90% | 56,536 psi | 89% | 2779 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 54,520 psi | 85% | 2756 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 84% | 55,593 psi | 87% | 2661 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 54,592 psi | 86% | 2720 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 57,624 psi | 90% | 2785 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 88% | 57,392 psi | 90% | 2779 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 56,014 psi | 88% | 2802 fps | 100% |
| Vihtavuori N560 | <<locked>> | 94% | 55,912 psi | 88% | 2877 fps | 99% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 55,390 psi | 87% | 2854 fps | 99.1% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 48,327 psi | 76% | 2792 fps | 96.9% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 53,969 psi | 85% | 2680 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 56,173 psi | 88% | 2802 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 98% | 54,418 psi | 85% | 2907 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 54,346 psi | 85% | 2749 fps | 99.6% |
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% | 33,025 psi | 52% | 2356 fps | 97.7% |
| Accurate 4350 | <<locked>> | 80% | 44,382 psi | 70% | 2592 fps | 100% |
| Accurate High Country | 95 gr | 82% | 38,189 psi | 60% | 2566 fps | 95.7% |
| Accurate MAGPRO | 101.5 gr | 86% | 41,452 psi | 65% | 2625 fps | 95.3% |
| ADI AR 2208 | <<locked>> | 80% | 52,475 psi | 82% | 2657 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 37,072 psi | 58% | 2474 fps | 96.3% |
| ADI AR 2213 | <<locked>> | 84% | 37,710 psi | 59% | 2516 fps | 95.1% |
| ADI AR 2217 | <<locked>> | 94% | 38,696 psi | 61% | 2536 fps | 95.7% |
| ADI AR 2225 | <<locked>> | 90% | 30,458 psi | 48% | 2385 fps | 95.6% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 37,405 psi | 59% | 2477 fps | 96.5% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 37,405 psi | 59% | 2477 fps | 96.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 53,534 psi | 84% | 2677 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 42,583 psi | 67% | 2598 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 48,892 psi | 77% | 2707 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 37,057 psi | 58% | 2470 fps | 96.4% |
| Alliant Reloder-22 | <<locked>> | 80% | 32,938 psi | 52% | 2415 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 80% | 31,720 psi | 50% | 2385 fps | 99.8% |
| Alliant Reloder-25 | <<locked>> | 80% | 27,688 psi | 43% | 2297 fps | 96.1% |
| Alliant Reloder-26 | <<locked>> | 80% | 34,287 psi | 54% | 2513 fps | 99.3% |
| Baschieri & Pellagri 109 | <<locked>> | 92% | 48,486 psi | 76% | 2661 fps | 95% |
| Bofors RP15 | <<locked>> | 84% | 34,954 psi | 55% | 2464 fps | 95.7% |
| Bofors RP30 | <<locked>> | 92% | 37,260 psi | 58% | 2552 fps | 95.9% |
| Bofors RP5 | <<locked>> | 80% | 32,938 psi | 52% | 2415 fps | 95% |
| Bofors RP7 | <<locked>> | 80% | 47,239 psi | 74% | 2592 fps | 99.3% |
| Hodgdon H1000 | <<locked>> | 90% | 37,115 psi | 58% | 2503 fps | 95.8% |
| Hodgdon H414 | <<locked>> | 80% | 45,992 psi | 72% | 2638 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 80% | 48,689 psi | 76% | 2654 fps | 99.2% |
| Hodgdon H4831 | <<locked>> | 84% | 40,219 psi | 63% | 2523 fps | 95.3% |
| Hodgdon H4831 SC | <<locked>> | 84% | 39,508 psi | 62% | 2507 fps | 95.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 40,147 psi | 63% | 2487 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 32,808 psi | 51% | 2484 fps | 95.4% |
| Hodgdon Superformance | <<locked>> | 80% | 45,223 psi | 71% | 2661 fps | 99.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,717 psi | 43% | 1516 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 42,757 psi | 67% | 2533 fps | 98.7% |
| IMR 4451 Enduron | <<locked>> | 80% | 48,588 psi | 76% | 2618 fps | 99.7% |
| IMR 4831 | <<locked>> | 80% | 42,235 psi | 66% | 2539 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 82% | 39,552 psi | 62% | 2470 fps | 95.3% |
| IMR 7828 SSC | <<locked>> | 86% | 38,769 psi | 61% | 2552 fps | 95.6% |
| Lovex S065 | <<locked>> | 80% | 46,282 psi | 73% | 2572 fps | 99.9% |
| Lovex S070 | <<locked>> | 80% | 44,498 psi | 70% | 2562 fps | 99.4% |
| Lovex S071 | <<locked>> | 80% | 28,514 psi | 45% | 2241 fps | 96% |
| Norma 204 | <<locked>> | 80% | 42,612 psi | 67% | 2569 fps | 97.8% |
| Norma 217 | <<locked>> | 94% | 30,792 psi | 48% | 2431 fps | 95.3% |
| Norma MRP | <<locked>> | 80% | 34,243 psi | 54% | 2477 fps | 97.1% |
| Norma URP | <<locked>> | 80% | 43,555 psi | 68% | 2579 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 38,348 psi | 60% | 2559 fps | 95.9% |
| Ramshot Hunter | <<locked>> | 80% | 42,395 psi | 66% | 2579 fps | 99.5% |
| Ramshot Magnum | <<locked>> | 84% | 31,792 psi | 50% | 2385 fps | 95.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,355 psi | 44% | 1555 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 51,938 psi | 81% | 2746 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 44,106 psi | 69% | 2612 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 42,409 psi | 66% | 2628 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 86% | 31,763 psi | 50% | 2457 fps | 96.2% |
| ReloadSwiss RS 80 | <<locked>> | 96% | 40,582 psi | 64% | 2657 fps | 95.2% |
| Rottweil R 903 | <<locked>> | 80% | 51,300 psi | 80% | 2644 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 38,435 psi | 60% | 2454 fps | 95.6% |
| Rottweil R 905 | <<locked>> | 80% | 36,303 psi | 57% | 2454 fps | 96.4% |
| Rottweil R 907 | <<locked>> | 80% | 47,239 psi | 74% | 2592 fps | 99.3% |
| Shooters World Long Rifle | <<locked>> | 80% | 46,282 psi | 73% | 2572 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 80% | 44,498 psi | 70% | 2562 fps | 99.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 52,634 psi | 82% | 2700 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 51,634 psi | 81% | 2526 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 45,223 psi | 71% | 2523 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 35,984 psi | 56% | 2451 fps | 96.2% |
| Somchem S355 | <<locked>> | 80% | 51,271 psi | 80% | 2641 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 41,640 psi | 65% | 2497 fps | 95.7% |
| Somchem S365 | <<locked>> | 80% | 40,466 psi | 63% | 2539 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 36,985 psi | 58% | 2441 fps | 97.4% |
| Vihtavuori N150 | <<locked>> | 80% | 48,979 psi | 77% | 2569 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 45,020 psi | 71% | 2572 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 31,923 psi | 50% | 2323 fps | 95.2% |
| Vihtavuori N550 | <<locked>> | 80% | 44,338 psi | 69% | 2579 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 35,491 psi | 56% | 2454 fps | 99.7% |
| Vihtavuori N560 | 97.3 gr | 84% | 39,711 psi | 62% | 2585 fps | 95.5% |
| Vihtavuori N565 | <<locked>> | 90% | 39,523 psi | 62% | 2572 fps | 95.7% |
| Vihtavuori N568 | <<locked>> | 96% | 42,134 psi | 66% | 2671 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 43,903 psi | 69% | 2536 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 46,108 psi | 72% | 2641 fps | 99.5% |
| Winchester StaBALL HD | <<locked>> | 80% | 28,108 psi | 44% | 2402 fps | 99.9% |
| Winchester Supreme 780 | <<locked>> | 80% | 33,591 psi | 53% | 2369 fps | 95.1% |
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 80 powders for .378 Weath. Mag. loaded with the .375 | 301gr | RWS UNI Classic. 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 80 of the 80 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 301.0 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, Accurate High Country rank at the top here: for .378 Weath. Mag. with the .375 | 301gr | RWS UNI Classic 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.