Load Specifications
Load data in caliber .378 Weath. Mag. with .374 | 350gr | Rhino Solid Shank 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 Hodgdon Retumbo.
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>> | 94% | 56,710 psi | 89% | 2556 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 54,520 psi | 85% | 2530 fps | 100% |
| Accurate MAGPRO | <<locked>> | 92% | 55,259 psi | 87% | 2661 fps | 99.3% |
| ADI AR 2209 | <<locked>> | 90% | 55,143 psi | 86% | 2592 fps | 100% |
| ADI AR 2213 | <<locked>> | 94% | 56,362 psi | 88% | 2651 fps | 99.8% |
| ADI AR 2217ᴾ | <<locked>> | 100% | 50,546 psi | 79% | 2569 fps | 99.6% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 45,078 psi | 71% | 2543 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 55,347 psi | 87% | 2589 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 86% | 55,405 psi | 87% | 2575 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 82% | 56,434 psi | 88% | 2589 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 90% | 54,679 psi | 86% | 2582 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 94% | 56,434 psi | 88% | 2648 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 94% | 54,215 psi | 85% | 2562 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 57,014 psi | 89% | 2671 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 90% | 54,201 psi | 85% | 2648 fps | 100% |
| Alliant Reloder-33ᴾ | <<locked>> | 100% | 46,601 psi | 73% | 2589 fps | 96.4% |
| Baschieri & Pellagri 109 | <<locked>> | 96% | 57,725 psi | 90% | 2618 fps | 98.4% |
| Bofors RP15 | <<locked>> | 96% | 55,608 psi | 87% | 2635 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 53,055 psi | 83% | 2638 fps | 99.9% |
| Bofors RP5 | <<locked>> | 94% | 56,434 psi | 88% | 2648 fps | 100% |
| Bofors RP7 | <<locked>> | 84% | 56,536 psi | 89% | 2526 fps | 100% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 55,753 psi | 87% | 2641 fps | 100% |
| Hodgdon H414 | <<locked>> | 84% | 56,043 psi | 88% | 2582 fps | 100% |
| Hodgdon H4350 | <<locked>> | 82% | 55,013 psi | 86% | 2543 fps | 100% |
| Hodgdon H4831 | <<locked>> | 92% | 56,260 psi | 88% | 2592 fps | 99.5% |
| Hodgdon H4831 SC | <<locked>> | 92% | 55,230 psi | 87% | 2579 fps | 99.4% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 55,738 psi | 87% | 2507 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 55,869 psi | 88% | 2749 fps | 100% |
| Hodgdon Superformance | <<locked>> | 84% | 56,202 psi | 88% | 2618 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,347 psi | 59% | 1558 fps | 100% |
| IMR 4350 | <<locked>> | 86% | 54,781 psi | 86% | 2523 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 82% | 54,520 psi | 85% | 2500 fps | 100% |
| IMR 4831 | <<locked>> | 86% | 54,839 psi | 86% | 2523 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 57,188 psi | 90% | 2572 fps | 99.6% |
| IMR 7828 SSC | <<locked>> | 94% | 54,418 psi | 85% | 2635 fps | 99.8% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 40,741 psi | 64% | 2461 fps | 98.3% |
| Lovex S065 | <<locked>> | 84% | 55,187 psi | 86% | 2497 fps | 100% |
| Lovex S070 | <<locked>> | 86% | 56,942 psi | 89% | 2546 fps | 100% |
| Lovex S071 | <<locked>> | 98% | 54,302 psi | 85% | 2526 fps | 100% |
| Norma 204 | <<locked>> | 86% | 55,564 psi | 87% | 2575 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 40,915 psi | 64% | 2487 fps | 99.7% |
| Norma MRP | <<locked>> | 92% | 56,434 psi | 88% | 2667 fps | 100% |
| Norma URP | <<locked>> | 86% | 56,463 psi | 88% | 2559 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 55,056 psi | 86% | 2654 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 86% | 55,172 psi | 86% | 2572 fps | 100% |
| Ramshot Magnum | <<locked>> | 98% | 57,319 psi | 90% | 2644 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,232 psi | 60% | 1598 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 54,375 psi | 85% | 2556 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 56,463 psi | 88% | 2631 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 56,434 psi | 88% | 2746 fps | 100% |
| ReloadSwiss RS 80ᴾ | <<locked>> | 100% | 51,372 psi | 81% | 2657 fps | 99.1% |
| Rottweil R 904 | <<locked>> | 90% | 56,144 psi | 88% | 2562 fps | 99.8% |
| Rottweil R 905 | <<locked>> | 90% | 54,085 psi | 85% | 2572 fps | 100% |
| Rottweil R 907 | <<locked>> | 84% | 56,536 psi | 89% | 2526 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 84% | 55,187 psi | 86% | 2497 fps | 100% |
| Shooters World SW4350 | <<locked>> | 86% | 56,942 psi | 89% | 2546 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 57,711 psi | 90% | 2392 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 54,418 psi | 85% | 2461 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 57,334 psi | 90% | 2615 fps | 100% |
| Somchem S355 | <<locked>> | 82% | 57,696 psi | 90% | 2510 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 57,551 psi | 90% | 2559 fps | 99.6% |
| Somchem S365 | <<locked>> | 88% | 57,072 psi | 89% | 2559 fps | 100% |
| Somchem S385 | <<locked>> | 90% | 54,650 psi | 86% | 2546 fps | 100% |
| Vihtavuori N150 | <<locked>> | 82% | 55,245 psi | 87% | 2441 fps | 100% |
| Vihtavuori N160 | <<locked>> | 84% | 54,650 psi | 86% | 2507 fps | 100% |
| Vihtavuori N165 | <<locked>> | 94% | 54,172 psi | 85% | 2530 fps | 100% |
| Vihtavuori N170ᴾ | <<locked>> | 100% | 56,115 psi | 88% | 2595 fps | 96.6% |
| Vihtavuori N550 | <<locked>> | 86% | 57,232 psi | 90% | 2559 fps | 100% |
| Vihtavuori N555 | <<locked>> | 92% | 56,565 psi | 89% | 2585 fps | 100% |
| Vihtavuori N560 | <<locked>> | 92% | 56,231 psi | 88% | 2671 fps | 99.7% |
| Vihtavuori N565 | <<locked>> | 98% | 55,985 psi | 88% | 2654 fps | 99.8% |
| Vihtavuori N568ᴾ | <<locked>> | 100% | 52,518 psi | 82% | 2657 fps | 98.9% |
| Vihtavuori N570ᴾ | <<locked>> | 100% | 49,588 psi | 78% | 2651 fps | 96.8% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 57,435 psi | 90% | 2510 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 56,202 psi | 88% | 2585 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 96% | 55,637 psi | 87% | 2690 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 54,389 psi | 85% | 2546 fps | 100% |
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% | 35,694 psi | 56% | 2231 fps | 99.4% |
| Accurate 4350 | <<locked>> | 80% | 47,688 psi | 75% | 2438 fps | 100% |
| Accurate MAGPRO | 89.3 gr | 80% | 36,390 psi | 57% | 2333 fps | 95.3% |
| ADI AR 2209 | <<locked>> | 80% | 39,639 psi | 62% | 2343 fps | 98.4% |
| ADI AR 2213 | <<locked>> | 80% | 35,389 psi | 55% | 2283 fps | 96% |
| ADI AR 2217 | <<locked>> | 88% | 34,200 psi | 54% | 2260 fps | 95.8% |
| ADI AR 2225 | <<locked>> | 84% | 27,122 psi | 43% | 2129 fps | 95.8% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 40,089 psi | 63% | 2343 fps | 98.5% |
| Alliant Reloder-16 | <<locked>> | 80% | 45,672 psi | 72% | 2441 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 52,649 psi | 83% | 2539 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 39,740 psi | 62% | 2339 fps | 98.5% |
| Alliant Reloder-22 | <<locked>> | 80% | 35,549 psi | 56% | 2293 fps | 97.6% |
| Alliant Reloder-23 | <<locked>> | 80% | 34,229 psi | 54% | 2254 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 29,776 psi | 47% | 2188 fps | 98.7% |
| Alliant Reloder-26 | <<locked>> | 80% | 37,536 psi | 59% | 2388 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 98% | 43,352 psi | 68% | 2530 fps | 95.4% |
| Baschieri & Pellagri 109 | <<locked>> | 86% | 42,627 psi | 67% | 2369 fps | 95% |
| Bofors RP15 | <<locked>> | 80% | 33,156 psi | 52% | 2241 fps | 96.6% |
| Bofors RP30 | <<locked>> | 84% | 31,096 psi | 49% | 2228 fps | 95.1% |
| Bofors RP5 | <<locked>> | 80% | 35,549 psi | 56% | 2293 fps | 97.6% |
| Bofors RP7 | <<locked>> | 80% | 49,995 psi | 78% | 2434 fps | 100% |
| Hodgdon H1000 | <<locked>> | 84% | 32,576 psi | 51% | 2224 fps | 95.8% |
| Hodgdon H414 | <<locked>> | 80% | 49,197 psi | 77% | 2487 fps | 100% |
| Hodgdon H4350 | <<locked>> | 80% | 51,677 psi | 81% | 2493 fps | 99.9% |
| Hodgdon H4831 | <<locked>> | 80% | 37,695 psi | 59% | 2287 fps | 96.2% |
| Hodgdon H4831 SC | <<locked>> | 80% | 37,101 psi | 58% | 2274 fps | 95.9% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 43,033 psi | 67% | 2333 fps | 100% |
| Hodgdon Retumbo | 84.4 gr | 80% | 29,066 psi | 46% | 2208 fps | 95.4% |
| Hodgdon Superformance | <<locked>> | 80% | 48,718 psi | 76% | 2513 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,978 psi | 44% | 1391 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 45,426 psi | 71% | 2382 fps | 99.8% |
| IMR 4451 Enduron | <<locked>> | 80% | 51,387 psi | 81% | 2457 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 45,237 psi | 71% | 2388 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 39,479 psi | 62% | 2287 fps | 96.8% |
| IMR 7828 SSC | <<locked>> | 80% | 34,055 psi | 53% | 2267 fps | 95.6% |
| IMR 8133 Enduron | <<locked>> | 92% | 31,531 psi | 49% | 2257 fps | 95% |
| Lovex S065 | <<locked>> | 80% | 48,907 psi | 77% | 2408 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 47,355 psi | 74% | 2411 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 30,821 psi | 48% | 2126 fps | 98.3% |
| Norma 204 | <<locked>> | 80% | 45,498 psi | 71% | 2425 fps | 99.3% |
| Norma 217 | <<locked>> | 88% | 27,717 psi | 43% | 2178 fps | 95.6% |
| Norma MRP | <<locked>> | 80% | 37,115 psi | 58% | 2356 fps | 99.1% |
| Norma URP | <<locked>> | 80% | 46,659 psi | 73% | 2425 fps | 100% |
| Ramshot Grand | 86.9 gr | 80% | 33,547 psi | 53% | 2270 fps | 95.8% |
| Ramshot Hunter | <<locked>> | 80% | 45,368 psi | 71% | 2428 fps | 100% |
| Ramshot Magnum | <<locked>> | 80% | 29,820 psi | 47% | 2169 fps | 96.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,587 psi | 45% | 1424 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 47,500 psi | 74% | 2457 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 45,542 psi | 71% | 2480 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 27,978 psi | 44% | 2185 fps | 96.2% |
| ReloadSwiss RS 80 | <<locked>> | 90% | 35,607 psi | 56% | 2369 fps | 95.2% |
| Rottweil R 904 | <<locked>> | 80% | 41,031 psi | 64% | 2320 fps | 97.8% |
| Rottweil R 905 | <<locked>> | 80% | 39,059 psi | 61% | 2326 fps | 98.5% |
| Rottweil R 907 | <<locked>> | 80% | 49,995 psi | 78% | 2434 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 80% | 48,907 psi | 77% | 2408 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 47,355 psi | 74% | 2411 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 54,288 psi | 85% | 2349 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 47,892 psi | 75% | 2369 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 38,725 psi | 61% | 2323 fps | 98.4% |
| Somchem S355 | <<locked>> | 80% | 54,201 psi | 85% | 2467 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 41,524 psi | 65% | 2313 fps | 97.1% |
| Somchem S365 | <<locked>> | 80% | 43,729 psi | 69% | 2385 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 39,639 psi | 62% | 2310 fps | 99.1% |
| Vihtavuori N150 | <<locked>> | 80% | 51,996 psi | 81% | 2402 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 48,080 psi | 75% | 2418 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 34,389 psi | 54% | 2201 fps | 97.6% |
| Vihtavuori N170 | <<locked>> | 96% | 49,081 psi | 77% | 2490 fps | 95% |
| Vihtavuori N550 | <<locked>> | 80% | 47,326 psi | 74% | 2425 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 38,435 psi | 60% | 2316 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 37,275 psi | 58% | 2346 fps | 96.3% |
| Vihtavuori N565 | <<locked>> | 84% | 35,085 psi | 55% | 2293 fps | 95.9% |
| Vihtavuori N568 | <<locked>> | 90% | 37,188 psi | 58% | 2382 fps | 95.1% |
| Vihtavuori N570 | <<locked>> | 96% | 43,178 psi | 68% | 2533 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 47,021 psi | 74% | 2379 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 49,197 psi | 77% | 2487 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 80% | 30,443 psi | 48% | 2290 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 36,187 psi | 57% | 2247 fps | 97.6% |
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 .374 | 350gr | Rhino Solid Shank. Hodgdon Retumbo delivers the highest muzzle velocity at 2,749 fps; across all powders the maximum-charge window runs from 1,558 fps to 2,749 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 59–90 %, leaving at least 10 % headroom. The 350.0 gr projectile in 0.374" calls for a 1:17.0 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, Hodgdon Retumbo rank at the top here: for .378 Weath. Mag. with the .374 | 350gr | Rhino Solid Shank 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.