Load Specifications
Load data in caliber .378 Weath. Mag. with .375 | 300gr | Woodleigh FMJ bullet and 82 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Accurate MAGPRO, Alliant Reloder-26 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 2700 | <<locked>> | 82% | 54,157 psi | 85% | 2664 fps | 99.8% |
| Accurate 3100 | <<locked>> | 96% | 56,681 psi | 89% | 2722 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 54,549 psi | 85% | 2753 fps | 100% |
| Accurate MAGPRO | <<locked>> | 96% | 55,753 psi | 87% | 2874 fps | 98% |
| ADI AR 2208 | <<locked>> | 82% | 55,825 psi | 87% | 2661 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 55,317 psi | 87% | 2756 fps | 99.4% |
| ADI AR 2213 | <<locked>> | 96% | 56,492 psi | 89% | 2813 fps | 98.9% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 47,543 psi | 75% | 2657 fps | 97.5% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 42,873 psi | 67% | 2622 fps | 99.1% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 55,434 psi | 87% | 2808 fps | 99.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 57,174 psi | 90% | 2683 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 88% | 55,463 psi | 87% | 2755 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 56,652 psi | 89% | 2770 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 54,752 psi | 86% | 2744 fps | 99.4% |
| Alliant Reloder-22 | <<locked>> | 96% | 56,347 psi | 88% | 2808 fps | 99.6% |
| Alliant Reloder-23 | <<locked>> | 98% | 57,406 psi | 90% | 2778 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 53,650 psi | 84% | 2785 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 92% | 53,911 psi | 84% | 2813 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 54,926 psi | 86% | 2722 fps | 96% |
| Bofors RP15 | <<locked>> | 98% | 55,317 psi | 87% | 2848 fps | 99.7% |
| Bofors RP30ᴾ | <<locked>> | 100% | 49,588 psi | 78% | 2727 fps | 98.3% |
| Bofors RP5 | <<locked>> | 96% | 56,347 psi | 88% | 2864 fps | 99.8% |
| Bofors RP7 | <<locked>> | 86% | 57,116 psi | 90% | 2701 fps | 99.9% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 48,588 psi | 76% | 2740 fps | 98.9% |
| Hodgdon H414 | <<locked>> | 84% | 57,392 psi | 90% | 2771 fps | 100% |
| Hodgdon H4350 | <<locked>> | 88% | 57,537 psi | 90% | 2795 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 98% | 55,811 psi | 87% | 2743 fps | 98.2% |
| Hodgdon H4831 SC | <<locked>> | 94% | 55,506 psi | 87% | 2738 fps | 98.2% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 55,709 psi | 87% | 2681 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 52,025 psi | 82% | 2910 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 56,753 psi | 89% | 2793 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,855 psi | 59% | 1679 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 55,071 psi | 86% | 2687 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 56,855 psi | 89% | 2675 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 55,143 psi | 86% | 2740 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 84% | 55,100 psi | 86% | 2723 fps | 100% |
| IMR 4831 | <<locked>> | 92% | 56,202 psi | 88% | 2712 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 57,725 psi | 90% | 2792 fps | 99% |
| IMR 7828 SSC | <<locked>> | 94% | 54,607 psi | 86% | 2796 fps | 98.7% |
| Lovex S065 | <<locked>> | 86% | 55,666 psi | 87% | 2672 fps | 100% |
| Lovex S070 | <<locked>> | 88% | 57,363 psi | 90% | 2720 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 54,868 psi | 86% | 2687 fps | 100% |
| Norma 204 | <<locked>> | 88% | 55,941 psi | 88% | 2742 fps | 99.4% |
| Norma 217ᴾ | <<locked>> | 100% | 37,869 psi | 59% | 2549 fps | 97.3% |
| Norma MRP | <<locked>> | 94% | 56,260 psi | 88% | 2832 fps | 100% |
| Norma URP | <<locked>> | 88% | 56,681 psi | 89% | 2736 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 54,244 psi | 85% | 2800 fps | 98.9% |
| Ramshot Hunter | <<locked>> | 88% | 55,332 psi | 87% | 2743 fps | 100% |
| Ramshot Magnum | <<locked>> | 96% | 55,100 psi | 86% | 2778 fps | 99.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,580 psi | 60% | 1719 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 56,043 psi | 88% | 2754 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 54,491 psi | 85% | 2726 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 56,579 psi | 89% | 2807 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 53,548 psi | 84% | 2847 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 48,457 psi | 76% | 2729 fps | 96.4% |
| Rottweil R 903 | <<locked>> | 82% | 54,882 psi | 86% | 2652 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 56,623 psi | 89% | 2727 fps | 98.9% |
| Rottweil R 905 | <<locked>> | 92% | 54,215 psi | 85% | 2733 fps | 99.4% |
| Rottweil R 907 | <<locked>> | 86% | 57,116 psi | 90% | 2701 fps | 99.9% |
| Shooters World Long Rifle | <<locked>> | 86% | 55,666 psi | 87% | 2672 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 57,363 psi | 90% | 2769 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 56,318 psi | 88% | 2708 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 55,085 psi | 86% | 2534 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 54,955 psi | 86% | 2629 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 57,363 psi | 90% | 2835 fps | 99.9% |
| Somchem S355 | <<locked>> | 82% | 54,607 psi | 86% | 2646 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 54,447 psi | 85% | 2668 fps | 98% |
| Somchem S365 | <<locked>> | 90% | 56,840 psi | 89% | 2736 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 54,737 psi | 86% | 2709 fps | 99.7% |
| Unknown powder | <<locked>> | 86% | 56,898 psi | 89% | 2738 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 56,492 psi | 89% | 2633 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 57,290 psi | 90% | 2708 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 55,811 psi | 87% | 2713 fps | 99.7% |
| Vihtavuori N550 | <<locked>> | 84% | 54,143 psi | 85% | 2702 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 56,275 psi | 88% | 2756 fps | 100% |
| Vihtavuori N560 | <<locked>> | 96% | 56,695 psi | 89% | 2838 fps | 98.7% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 57,029 psi | 89% | 2805 fps | 98.7% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 49,255 psi | 77% | 2737 fps | 96.1% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 54,186 psi | 85% | 2641 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 57,392 psi | 90% | 2771 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 98% | 55,796 psi | 87% | 2860 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 56,173 psi | 88% | 2727 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 2700 | <<locked>> | 80% | 50,807 psi | 80% | 2615 fps | 99.6% |
| Accurate 3100 | <<locked>> | 80% | 33,170 psi | 52% | 2307 fps | 97% |
| Accurate 4350 | <<locked>> | 80% | 44,541 psi | 70% | 2598 fps | 100% |
| Accurate MAGPRO | 106.9 gr | 90% | 45,266 psi | 71% | 2697 fps | 95.7% |
| ADI AR 2208 | <<locked>> | 80% | 52,634 psi | 82% | 2615 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 37,202 psi | 58% | 2425 fps | 95.6% |
| ADI AR 2213 | <<locked>> | 86% | 40,567 psi | 64% | 2526 fps | 95.2% |
| ADI AR 2217 | <<locked>> | 96% | 41,452 psi | 65% | 2542 fps | 95.8% |
| ADI AR 2225 | <<locked>> | 92% | 32,634 psi | 51% | 2391 fps | 95.7% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 37,536 psi | 59% | 2480 fps | 96.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 53,722 psi | 84% | 2636 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 42,772 psi | 67% | 2553 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 49,240 psi | 77% | 2664 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 37,202 psi | 58% | 2421 fps | 95.6% |
| Alliant Reloder-22 | <<locked>> | 82% | 35,317 psi | 55% | 2418 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 80% | 31,865 psi | 50% | 2336 fps | 99.5% |
| Alliant Reloder-25 | <<locked>> | 80% | 27,804 psi | 44% | 2243 fps | 95.1% |
| Alliant Reloder-26 | 96.1 gr | 80% | 34,534 psi | 54% | 2460 fps | 98.8% |
| Baschieri & Pellagri 109 | <<locked>> | 94% | 51,764 psi | 81% | 2669 fps | 95.2% |
| Bofors RP15 | <<locked>> | 84% | 35,186 psi | 55% | 2470 fps | 95.7% |
| Bofors RP30 | <<locked>> | 92% | 37,463 psi | 59% | 2499 fps | 95% |
| Bofors RP5 | <<locked>> | 80% | 33,069 psi | 52% | 2421 fps | 95% |
| Bofors RP7 | <<locked>> | 80% | 47,529 psi | 74% | 2550 fps | 99% |
| Hodgdon H1000 | <<locked>> | 92% | 37,405 psi | 59% | 2513 fps | 95.9% |
| Hodgdon H414 | <<locked>> | 80% | 50,198 psi | 79% | 2661 fps | 99.6% |
| Hodgdon H4350 | <<locked>> | 80% | 44,976 psi | 70% | 2589 fps | 98.6% |
| Hodgdon H4831 | <<locked>> | 90% | 43,178 psi | 68% | 2529 fps | 95.4% |
| Hodgdon H4831 SC | <<locked>> | 86% | 42,540 psi | 67% | 2518 fps | 95.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 40,335 psi | 63% | 2444 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 32,880 psi | 52% | 2487 fps | 95.3% |
| Hodgdon Superformance | <<locked>> | 80% | 45,469 psi | 71% | 2613 fps | 98.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,717 psi | 43% | 1497 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 51,721 psi | 81% | 2638 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 50,401 psi | 79% | 2577 fps | 99.6% |
| IMR 4350 | <<locked>> | 80% | 42,917 psi | 67% | 2536 fps | 98.7% |
| IMR 4451 Enduron | <<locked>> | 80% | 48,733 psi | 76% | 2621 fps | 99.7% |
| IMR 4831 | <<locked>> | 80% | 38,609 psi | 61% | 2422 fps | 99.6% |
| IMR 4955 Enduron | <<locked>> | 82% | 39,653 psi | 62% | 2477 fps | 95.3% |
| IMR 7828 SSC | <<locked>> | 86% | 41,495 psi | 65% | 2559 fps | 95.7% |
| Lovex S065 | <<locked>> | 80% | 46,441 psi | 73% | 2527 fps | 99.8% |
| Lovex S070 | <<locked>> | 80% | 44,657 psi | 70% | 2517 fps | 99.1% |
| Lovex S071 | <<locked>> | 80% | 28,601 psi | 45% | 2192 fps | 95.1% |
| Norma 204 | <<locked>> | 80% | 42,757 psi | 67% | 2518 fps | 97.1% |
| Norma 217 | <<locked>> | 96% | 33,112 psi | 52% | 2435 fps | 95.4% |
| Norma MRP | <<locked>> | 80% | 34,476 psi | 54% | 2427 fps | 96.3% |
| Norma URP | <<locked>> | 80% | 43,743 psi | 69% | 2533 fps | 99.9% |
| Ramshot Grand | 101 gr | 84% | 40,350 psi | 63% | 2549 fps | 95.7% |
| Ramshot Hunter | <<locked>> | 80% | 42,540 psi | 67% | 2531 fps | 99.2% |
| Ramshot Magnum | <<locked>> | 84% | 35,070 psi | 55% | 2414 fps | 95.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,355 psi | 44% | 1534 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 52,257 psi | 82% | 2704 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 44,411 psi | 70% | 2567 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 42,554 psi | 67% | 2580 fps | 99.8% |
| ReloadSwiss RS 76 | <<locked>> | 86% | 31,952 psi | 50% | 2400 fps | 95.1% |
| ReloadSwiss RS 80 | <<locked>> | 98% | 43,903 psi | 69% | 2666 fps | 95.4% |
| Rottweil R 903 | <<locked>> | 80% | 51,474 psi | 81% | 2604 fps | 100% |
| Rottweil R 904 | <<locked>> | 82% | 41,147 psi | 64% | 2461 fps | 95.7% |
| Rottweil R 905 | <<locked>> | 80% | 36,492 psi | 57% | 2408 fps | 95.6% |
| Rottweil R 907 | <<locked>> | 80% | 47,529 psi | 74% | 2550 fps | 99% |
| Shooters World Long Rifle | <<locked>> | 80% | 46,441 psi | 73% | 2527 fps | 99.8% |
| Shooters World SW4350 | <<locked>> | 80% | 44,657 psi | 70% | 2569 fps | 99.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 52,765 psi | 83% | 2658 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 51,677 psi | 81% | 2488 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 45,353 psi | 71% | 2479 fps | 99.1% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 36,172 psi | 57% | 2457 fps | 96.3% |
| Somchem S355 | <<locked>> | 80% | 51,459 psi | 81% | 2600 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 41,858 psi | 66% | 2451 fps | 95% |
| Somchem S365 | <<locked>> | 80% | 40,654 psi | 64% | 2494 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 37,115 psi | 58% | 2394 fps | 96.7% |
| Unknown powder | <<locked>> | 80% | 46,891 psi | 73% | 2586 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 80% | 44,179 psi | 69% | 2454 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 46,920 psi | 74% | 2557 fps | 100% |
| Vihtavuori N165 | <<locked>> | 84% | 35,578 psi | 56% | 2357 fps | 95.8% |
| Vihtavuori N550 | <<locked>> | 80% | 47,558 psi | 75% | 2599 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 35,795 psi | 56% | 2408 fps | 99.4% |
| Vihtavuori N560 | <<locked>> | 88% | 43,366 psi | 68% | 2608 fps | 95.8% |
| Vihtavuori N565 | <<locked>> | 92% | 42,511 psi | 67% | 2578 fps | 95.8% |
| Vihtavuori N568 | <<locked>> | 98% | 45,905 psi | 72% | 2677 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 44,121 psi | 69% | 2495 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 50,198 psi | 79% | 2661 fps | 99.6% |
| Winchester StaBALL HD | <<locked>> | 80% | 28,224 psi | 44% | 2345 fps | 99.5% |
| Winchester Supreme 780 | <<locked>> | 80% | 36,811 psi | 58% | 2389 fps | 95.5% |
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 82 powders for .378 Weath. Mag. loaded with the .375 | 300gr | Woodleigh FMJ. Hodgdon Retumbo delivers the highest muzzle velocity at 2,910 fps; across all powders the maximum-charge window runs from 1,679 fps to 2,910 fps. ADI AR 2217 gives the best case fill at 100 %, and 82 of the 82 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 59–90 %, 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. Accurate MAGPRO, Alliant Reloder-26, Ramshot Grand rank at the top here: for .378 Weath. Mag. with the .375 | 300gr | Woodleigh FMJ 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.