Load Specifications
Load data in caliber .378 Weath. Mag. with .375 | 300gr | Woodleigh PP SN bullet and 77 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Accurate MAGPRO, Ramshot Grand and Alliant Reloder-26.
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% | 56,971 psi | 89% | 2779 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 54,882 psi | 86% | 2759 fps | 100% |
| Accurate MAGPRO | <<locked>> | 94% | 55,448 psi | 87% | 2877 fps | 98.5% |
| ADI AR 2208 | <<locked>> | 82% | 56,159 psi | 88% | 2713 fps | 100% |
| ADI AR 2209 | <<locked>> | 92% | 55,608 psi | 87% | 2818 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 96% | 56,913 psi | 89% | 2877 fps | 99.3% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 47,630 psi | 75% | 2720 fps | 98.3% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 42,293 psi | 66% | 2687 fps | 99.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 57,508 psi | 90% | 2736 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 88% | 55,622 psi | 87% | 2808 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 56,797 psi | 89% | 2825 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 55,027 psi | 86% | 2805 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 96% | 56,782 psi | 89% | 2871 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 96% | 54,302 psi | 85% | 2789 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 53,388 psi | 84% | 2848 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 92% | 54,418 psi | 85% | 2877 fps | 100% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 55,259 psi | 87% | 2785 fps | 96.7% |
| Bofors RP15 | <<locked>> | 98% | 55,767 psi | 87% | 2858 fps | 99.8% |
| Bofors RP30ᴾ | <<locked>> | 100% | 49,385 psi | 77% | 2792 fps | 98.9% |
| Bofors RP5 | <<locked>> | 96% | 56,782 psi | 89% | 2871 fps | 99.9% |
| Bofors RP7 | <<locked>> | 86% | 57,435 psi | 90% | 2759 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 52,446 psi | 82% | 2805 fps | 99.4% |
| Hodgdon H414 | <<locked>> | 86% | 56,579 psi | 89% | 2812 fps | 100% |
| Hodgdon H4350 | <<locked>> | 84% | 55,782 psi | 87% | 2772 fps | 99.8% |
| Hodgdon H4831 | <<locked>> | 94% | 56,927 psi | 89% | 2815 fps | 98.9% |
| Hodgdon H4831 SC | <<locked>> | 94% | 55,782 psi | 87% | 2799 fps | 98.7% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 56,057 psi | 88% | 2733 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 52,301 psi | 82% | 2917 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 57,014 psi | 89% | 2851 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,999 psi | 58% | 1706 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 55,390 psi | 87% | 2746 fps | 99.9% |
| IMR 4451 Enduron | <<locked>> | 84% | 55,390 psi | 87% | 2730 fps | 100% |
| IMR 4831 | <<locked>> | 88% | 55,245 psi | 87% | 2749 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 54,578 psi | 86% | 2746 fps | 98.7% |
| IMR 7828 SSC | <<locked>> | 96% | 54,708 psi | 86% | 2854 fps | 99.2% |
| Lovex S065 | <<locked>> | 86% | 55,999 psi | 88% | 2726 fps | 100% |
| Lovex S070 | <<locked>> | 88% | 57,479 psi | 90% | 2772 fps | 100% |
| Lovex S071ᴾ | <<locked>> | 100% | 54,317 psi | 85% | 2743 fps | 100% |
| Norma 204 | <<locked>> | 88% | 56,173 psi | 88% | 2802 fps | 99.7% |
| Norma 217ᴾ | <<locked>> | 100% | 37,913 psi | 59% | 2615 fps | 98.2% |
| Norma MRP | <<locked>> | 94% | 56,521 psi | 89% | 2890 fps | 100% |
| Norma URP | <<locked>> | 88% | 56,840 psi | 89% | 2789 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 55,347 psi | 87% | 2874 fps | 99.5% |
| Ramshot Hunter | <<locked>> | 88% | 55,622 psi | 87% | 2802 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 57,551 psi | 90% | 2867 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,898 psi | 59% | 1749 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 56,434 psi | 88% | 2808 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 54,752 psi | 86% | 2782 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 56,884 psi | 89% | 2864 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 52,692 psi | 83% | 2910 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 47,587 psi | 75% | 2799 fps | 97.3% |
| Rottweil R 903 | <<locked>> | 82% | 55,245 psi | 87% | 2707 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 56,898 psi | 89% | 2785 fps | 99.3% |
| Rottweil R 905 | <<locked>> | 92% | 54,520 psi | 85% | 2792 fps | 99.7% |
| Rottweil R 907 | <<locked>> | 86% | 57,435 psi | 90% | 2759 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 86% | 55,999 psi | 88% | 2726 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 57,479 psi | 90% | 2772 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 56,652 psi | 89% | 2762 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 55,230 psi | 87% | 2579 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 55,259 psi | 87% | 2684 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 54,085 psi | 85% | 2789 fps | 99.7% |
| Somchem S355 | <<locked>> | 82% | 54,955 psi | 86% | 2700 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 54,781 psi | 86% | 2726 fps | 98.5% |
| Somchem S365 | <<locked>> | 90% | 57,188 psi | 90% | 2792 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 54,998 psi | 86% | 2766 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 84% | 56,072 psi | 88% | 2671 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 55,187 psi | 86% | 2733 fps | 100% |
| Vihtavuori N165 | <<locked>> | 96% | 54,491 psi | 85% | 2746 fps | 99.8% |
| Vihtavuori N550 | <<locked>> | 86% | 54,375 psi | 85% | 2743 fps | 100% |
| Vihtavuori N555 | <<locked>> | 94% | 56,579 psi | 89% | 2812 fps | 100% |
| Vihtavuori N560 | <<locked>> | 94% | 56,420 psi | 88% | 2890 fps | 99.1% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 55,970 psi | 88% | 2867 fps | 99.1% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 48,965 psi | 77% | 2805 fps | 97% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 54,447 psi | 85% | 2694 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 56,710 psi | 89% | 2815 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 98% | 55,129 psi | 86% | 2920 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 54,926 psi | 86% | 2766 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% | 33,315 psi | 52% | 2365 fps | 97.8% |
| Accurate 4350 | <<locked>> | 80% | 44,759 psi | 70% | 2602 fps | 100% |
| Accurate MAGPRO | 102.7 gr | 86% | 41,930 psi | 66% | 2638 fps | 95.5% |
| ADI AR 2208 | <<locked>> | 80% | 52,808 psi | 83% | 2667 fps | 100% |
| ADI AR 2209 | <<locked>> | 80% | 37,347 psi | 59% | 2484 fps | 96.4% |
| ADI AR 2213 | <<locked>> | 84% | 38,145 psi | 60% | 2530 fps | 95.2% |
| ADI AR 2217 | <<locked>> | 94% | 39,059 psi | 61% | 2549 fps | 95.8% |
| ADI AR 2225 | <<locked>> | 90% | 30,792 psi | 48% | 2398 fps | 95.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 54,056 psi | 85% | 2690 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 42,946 psi | 67% | 2608 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 49,414 psi | 77% | 2720 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 37,376 psi | 59% | 2484 fps | 96.5% |
| Alliant Reloder-22 | <<locked>> | 80% | 33,214 psi | 52% | 2428 fps | 95.1% |
| Alliant Reloder-23 | <<locked>> | 80% | 32,039 psi | 50% | 2395 fps | 99.8% |
| Alliant Reloder-25 | <<locked>> | 80% | 27,920 psi | 44% | 2306 fps | 96.3% |
| Alliant Reloder-26 | 96.6 gr | 80% | 34,780 psi | 55% | 2526 fps | 99.4% |
| Baschieri & Pellagri 109 | <<locked>> | 92% | 48,791 psi | 76% | 2674 fps | 95.1% |
| Bofors RP15 | <<locked>> | 84% | 35,346 psi | 55% | 2477 fps | 95.8% |
| Bofors RP30 | <<locked>> | 90% | 35,331 psi | 55% | 2510 fps | 95.1% |
| Bofors RP5 | <<locked>> | 80% | 33,214 psi | 52% | 2428 fps | 95.1% |
| Bofors RP7 | <<locked>> | 80% | 47,674 psi | 75% | 2605 fps | 99.4% |
| Hodgdon H1000 | <<locked>> | 90% | 37,492 psi | 59% | 2516 fps | 96% |
| Hodgdon H414 | <<locked>> | 80% | 46,456 psi | 73% | 2651 fps | 99.6% |
| Hodgdon H4350 | <<locked>> | 80% | 49,008 psi | 77% | 2661 fps | 99.2% |
| Hodgdon H4831 | <<locked>> | 84% | 40,727 psi | 64% | 2536 fps | 95.5% |
| Hodgdon H4831 SC | <<locked>> | 84% | 40,001 psi | 63% | 2523 fps | 95.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 40,538 psi | 64% | 2497 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 86% | 33,112 psi | 52% | 2493 fps | 95.5% |
| Hodgdon Superformance | <<locked>> | 80% | 45,745 psi | 72% | 2674 fps | 99.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,789 psi | 44% | 1522 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 43,047 psi | 67% | 2543 fps | 98.8% |
| IMR 4451 Enduron | <<locked>> | 80% | 49,023 psi | 77% | 2631 fps | 99.7% |
| IMR 4831 | <<locked>> | 80% | 42,728 psi | 67% | 2552 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 82% | 39,885 psi | 63% | 2484 fps | 95.4% |
| IMR 7828 SSC | <<locked>> | 86% | 39,131 psi | 61% | 2566 fps | 95.7% |
| Lovex S065 | <<locked>> | 80% | 46,586 psi | 73% | 2582 fps | 99.9% |
| Lovex S070 | <<locked>> | 80% | 44,918 psi | 70% | 2575 fps | 99.5% |
| Lovex S071 | <<locked>> | 80% | 28,834 psi | 45% | 2254 fps | 96.1% |
| Norma 204 | <<locked>> | 80% | 43,033 psi | 67% | 2579 fps | 97.8% |
| Norma 217 | <<locked>> | 94% | 31,241 psi | 49% | 2448 fps | 95.5% |
| Norma MRP | <<locked>> | 80% | 34,635 psi | 54% | 2490 fps | 97.2% |
| Norma URP | <<locked>> | 80% | 44,034 psi | 69% | 2592 fps | 100% |
| Ramshot Grand | 97.6 gr | 84% | 36,114 psi | 57% | 2510 fps | 95% |
| Ramshot Hunter | <<locked>> | 80% | 42,830 psi | 67% | 2592 fps | 99.6% |
| Ramshot Magnum | <<locked>> | 84% | 32,169 psi | 50% | 2398 fps | 95.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,427 psi | 45% | 1562 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 52,475 psi | 82% | 2756 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 44,585 psi | 70% | 2621 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 42,844 psi | 67% | 2641 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 84% | 30,008 psi | 47% | 2405 fps | 95.1% |
| ReloadSwiss RS 80 | <<locked>> | 96% | 41,031 psi | 64% | 2671 fps | 95.4% |
| Rottweil R 903 | <<locked>> | 80% | 51,851 psi | 81% | 2657 fps | 100% |
| Rottweil R 904 | <<locked>> | 80% | 38,870 psi | 61% | 2467 fps | 95.7% |
| Rottweil R 905 | <<locked>> | 80% | 36,753 psi | 58% | 2470 fps | 96.5% |
| Rottweil R 907 | <<locked>> | 80% | 47,674 psi | 75% | 2605 fps | 99.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 46,586 psi | 73% | 2582 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 80% | 44,918 psi | 70% | 2575 fps | 99.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 53,084 psi | 83% | 2713 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 52,011 psi | 82% | 2536 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 45,527 psi | 71% | 2530 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 36,419 psi | 57% | 2464 fps | 96.4% |
| Somchem S355 | <<locked>> | 80% | 51,648 psi | 81% | 2651 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 39,378 psi | 62% | 2454 fps | 95% |
| Somchem S365 | <<locked>> | 80% | 40,828 psi | 64% | 2549 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 37,246 psi | 58% | 2451 fps | 97.5% |
| Vihtavuori N150 | <<locked>> | 80% | 49,458 psi | 78% | 2582 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 45,368 psi | 71% | 2582 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 32,213 psi | 50% | 2333 fps | 95.3% |
| Vihtavuori N550 | <<locked>> | 80% | 44,788 psi | 70% | 2589 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 35,955 psi | 56% | 2467 fps | 99.8% |
| Vihtavuori N560 | <<locked>> | 84% | 40,074 psi | 63% | 2598 fps | 95.6% |
| Vihtavuori N565 | <<locked>> | 90% | 39,972 psi | 63% | 2585 fps | 95.9% |
| Vihtavuori N568 | <<locked>> | 96% | 42,641 psi | 67% | 2687 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 44,382 psi | 70% | 2546 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 46,586 psi | 73% | 2654 fps | 99.6% |
| Winchester StaBALL HD | <<locked>> | 80% | 28,413 psi | 45% | 2411 fps | 99.9% |
| Winchester Supreme 780 | <<locked>> | 80% | 33,982 psi | 53% | 2379 fps | 95.3% |
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 77 powders for .378 Weath. Mag. loaded with the .375 | 300gr | Woodleigh PP SN. Winchester StaBALL HD delivers the highest muzzle velocity at 2,920 fps; across all powders the maximum-charge window runs from 1,706 fps to 2,920 fps. ADI AR 2217 gives the best case fill at 100 %, and 77 of the 77 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. Accurate MAGPRO, Ramshot Grand, Alliant Reloder-26 rank at the top here: for .378 Weath. Mag. with the .375 | 300gr | Woodleigh PP SN 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.