Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 170gr | Speer Hot-Cor bullet and 51 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Retumbo, ADI AR 2218 and Vihtavuori N570.
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>> | 86% | 56,144 psi | 88% | 3107 fps | 100% |
| Accurate High Country | <<locked>> | 82% | 54,201 psi | 85% | 3209 fps | 99.7% |
| Accurate MAGPRO | <<locked>> | 84% | 55,216 psi | 87% | 3219 fps | 99.2% |
| ADI AR 2209 | <<locked>> | 84% | 57,116 psi | 90% | 3199 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 55,825 psi | 87% | 3215 fps | 99.8% |
| ADI AR 2217 | <<locked>> | 94% | 54,882 psi | 86% | 3192 fps | 99.9% |
| ADI AR 2218 | <<locked>> | 98% | 55,506 psi | 87% | 3317 fps | 98.4% |
| ADI AR 2225 | <<locked>> | 96% | 54,244 psi | 85% | 3219 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 57,276 psi | 90% | 3196 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 56,681 psi | 89% | 3186 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 86% | 56,362 psi | 88% | 3212 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 54,505 psi | 85% | 3114 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 55,013 psi | 86% | 3189 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 55,187 psi | 86% | 3202 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 96% | 57,479 psi | 90% | 3294 fps | 98.5% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 57,479 psi | 90% | 3281 fps | 98% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 56,231 psi | 88% | 3173 fps | 98.4% |
| Bofors RP15 | <<locked>> | 88% | 55,738 psi | 87% | 3199 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 54,984 psi | 86% | 3205 fps | 99.9% |
| Bofors RP5 | <<locked>> | 86% | 56,362 psi | 88% | 3212 fps | 100% |
| Hodgdon H1000 | <<locked>> | 92% | 56,318 psi | 88% | 3215 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 54,708 psi | 86% | 3143 fps | 99.4% |
| Hodgdon H4831 SC | <<locked>> | 86% | 57,450 psi | 90% | 3189 fps | 99.6% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 57,246 psi | 90% | 3097 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 90% | 54,230 psi | 85% | 3281 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,869 psi | 59% | 2067 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 55,013 psi | 86% | 3120 fps | 99.5% |
| IMR 7828 SSC | <<locked>> | 86% | 54,273 psi | 85% | 3199 fps | 99.7% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 57,087 psi | 89% | 3258 fps | 100% |
| Lovex S071 | <<locked>> | 90% | 54,520 psi | 85% | 3081 fps | 100% |
| Norma 217 | <<locked>> | 98% | 54,636 psi | 86% | 3219 fps | 100% |
| Norma MRP | <<locked>> | 84% | 56,507 psi | 89% | 3228 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 55,521 psi | 87% | 3219 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 88% | 54,143 psi | 85% | 3143 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,798 psi | 61% | 2113 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 55,158 psi | 86% | 3264 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 54,476 psi | 85% | 3225 fps | 99.3% |
| Rottweil R 904 | <<locked>> | 84% | 57,377 psi | 90% | 3166 fps | 99.8% |
| Rottweil R 905 | <<locked>> | 84% | 56,565 psi | 89% | 3182 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 56,202 psi | 88% | 3179 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 55,114 psi | 86% | 3094 fps | 99.4% |
| Somchem S385 | <<locked>> | 84% | 56,753 psi | 89% | 3143 fps | 100% |
| Vihtavuori N165 | <<locked>> | 88% | 56,913 psi | 89% | 3133 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 56,318 psi | 88% | 3156 fps | 96.8% |
| Vihtavuori N555 | <<locked>> | 84% | 56,260 psi | 88% | 3143 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 55,840 psi | 88% | 3228 fps | 99.6% |
| Vihtavuori N565 | <<locked>> | 90% | 57,116 psi | 90% | 3222 fps | 99.8% |
| Vihtavuori N568 | <<locked>> | 92% | 54,897 psi | 86% | 3228 fps | 99% |
| Vihtavuori N570 | <<locked>> | 94% | 56,405 psi | 88% | 3301 fps | 97.9% |
| Winchester StaBALL HD | <<locked>> | 86% | 55,013 psi | 86% | 3205 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 56,623 psi | 89% | 3143 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% | 45,832 psi | 72% | 2930 fps | 100% |
| Accurate High Country | <<locked>> | 80% | 50,502 psi | 79% | 3143 fps | 99.3% |
| Accurate MAGPRO | <<locked>> | 80% | 47,877 psi | 75% | 3077 fps | 98% |
| ADI AR 2209 | <<locked>> | 80% | 49,879 psi | 78% | 3074 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 80% | 45,165 psi | 71% | 3015 fps | 98.4% |
| ADI AR 2217 | <<locked>> | 82% | 36,100 psi | 57% | 2795 fps | 96.1% |
| ADI AR 2218 | 112.5 gr | 92% | 44,425 psi | 70% | 3074 fps | 95.1% |
| ADI AR 2225 | <<locked>> | 80% | 31,038 psi | 49% | 2694 fps | 97% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 50,169 psi | 79% | 3071 fps | 99.7% |
| Alliant Reloder-19 | <<locked>> | 80% | 49,705 psi | 78% | 3064 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 80% | 45,934 psi | 72% | 3018 fps | 99.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 44,657 psi | 70% | 2946 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 38,856 psi | 61% | 2887 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 80% | 51,169 psi | 80% | 3133 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 90% | 45,774 psi | 72% | 3064 fps | 95.6% |
| Alliant Reloder-50 | <<locked>> | 94% | 45,876 psi | 72% | 3058 fps | 95.1% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 43,236 psi | 68% | 2917 fps | 95.2% |
| Bofors RP15 | <<locked>> | 80% | 42,743 psi | 67% | 2949 fps | 98.7% |
| Bofors RP30 | <<locked>> | 80% | 36,318 psi | 57% | 2812 fps | 96.2% |
| Bofors RP5 | <<locked>> | 80% | 45,934 psi | 72% | 3018 fps | 99.3% |
| Hodgdon H1000 | <<locked>> | 80% | 36,637 psi | 57% | 2815 fps | 96.9% |
| Hodgdon H4831 | <<locked>> | 80% | 47,616 psi | 75% | 3009 fps | 98.3% |
| Hodgdon H4831 SC | <<locked>> | 80% | 46,818 psi | 73% | 2995 fps | 98.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 53,708 psi | 84% | 3045 fps | 100% |
| Hodgdon Retumbo | 92.3 gr | 80% | 37,956 psi | 59% | 2936 fps | 98.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,369 psi | 44% | 1850 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 48,327 psi | 76% | 2995 fps | 98.6% |
| IMR 7828 SSC | <<locked>> | 80% | 43,947 psi | 69% | 2995 fps | 98.1% |
| IMR 8133 Enduron | <<locked>> | 86% | 35,201 psi | 55% | 2799 fps | 95.5% |
| Lovex S071 | <<locked>> | 80% | 39,494 psi | 62% | 2802 fps | 99.6% |
| Norma 217 | <<locked>> | 82% | 30,951 psi | 49% | 2697 fps | 96% |
| Norma MRP | <<locked>> | 80% | 49,008 psi | 77% | 3097 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 44,324 psi | 69% | 3012 fps | 98.5% |
| Ramshot Magnum | <<locked>> | 80% | 40,016 psi | 63% | 2874 fps | 98.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,138 psi | 46% | 1896 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 37,463 psi | 59% | 2907 fps | 99.2% |
| ReloadSwiss RS 80 | <<locked>> | 84% | 40,190 psi | 63% | 2930 fps | 96% |
| Rottweil R 904 | <<locked>> | 80% | 50,444 psi | 79% | 3045 fps | 99.2% |
| Rottweil R 905 | <<locked>> | 80% | 49,414 psi | 77% | 3054 fps | 99.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 49,066 psi | 77% | 3051 fps | 99.7% |
| Somchem S361 | <<locked>> | 80% | 51,605 psi | 81% | 3031 fps | 99% |
| Somchem S385 | <<locked>> | 80% | 49,806 psi | 78% | 3025 fps | 99.9% |
| Vihtavuori N165 | <<locked>> | 80% | 43,642 psi | 68% | 2894 fps | 99.3% |
| Vihtavuori N170 | <<locked>> | 88% | 49,153 psi | 77% | 3022 fps | 95% |
| Vihtavuori N555 | <<locked>> | 80% | 49,371 psi | 77% | 3031 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 48,530 psi | 76% | 3091 fps | 98.6% |
| Vihtavuori N565 | <<locked>> | 80% | 40,495 psi | 63% | 2894 fps | 96.9% |
| Vihtavuori N568 | <<locked>> | 84% | 41,191 psi | 65% | 2949 fps | 95.8% |
| Vihtavuori N570 | 105.4 gr | 88% | 45,353 psi | 71% | 3081 fps | 95% |
| Winchester StaBALL HD | <<locked>> | 80% | 43,714 psi | 69% | 3015 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 46,050 psi | 72% | 2953 fps | 99.3% |
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 51 powders for .30-378 Weath. Mag. loaded with the .308 | 170gr | Speer Hot-Cor. ADI AR 2218 delivers the highest muzzle velocity at 3,317 fps; across all powders the maximum-charge window runs from 2,067 fps to 3,317 fps. Alliant Reloder-50 gives the best case fill at 100 %, and 51 of the 51 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 170.0 gr projectile in 0.308" calls for a 1:14.5 twist; slower twists will usually not stabilise this weight. Alliant Reloder-50, Hodgdon TrailBoss, IMR 8133 Enduron 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. Hodgdon Retumbo, ADI AR 2218, Vihtavuori N570 rank at the top here: for .30-378 Weath. Mag. with the .308 | 170gr | Speer Hot-Cor 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.