Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 180gr | Sierra GameKing bullet and 52 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ADI AR 2218, Vihtavuori N570 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>> | 84% | 54,041 psi | 85% | 3002 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 49,255 psi | 77% | 3022 fps | 96.8% |
| Accurate High Country | <<locked>> | 82% | 55,927 psi | 88% | 3166 fps | 99.9% |
| Accurate MAGPRO | <<locked>> | 84% | 56,884 psi | 89% | 3176 fps | 99.6% |
| ADI AR 2209 | <<locked>> | 82% | 54,839 psi | 86% | 3091 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 57,421 psi | 90% | 3173 fps | 100% |
| ADI AR 2217 | <<locked>> | 94% | 56,768 psi | 89% | 3153 fps | 100% |
| ADI AR 2218 | <<locked>> | 98% | 57,406 psi | 90% | 3287 fps | 99.1% |
| ADI AR 2225 | <<locked>> | 96% | 56,202 psi | 88% | 3176 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 82% | 55,071 psi | 86% | 3087 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 54,520 psi | 85% | 3081 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 84% | 54,172 psi | 85% | 3104 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 56,130 psi | 88% | 3064 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 56,826 psi | 89% | 3143 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 56,985 psi | 89% | 3153 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 55,332 psi | 87% | 3189 fps | 98.5% |
| Alliant Reloder-50 | <<locked>> | 98% | 55,288 psi | 87% | 3179 fps | 98.1% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 57,580 psi | 90% | 3127 fps | 98.9% |
| Bofors RP15 | <<locked>> | 88% | 57,305 psi | 90% | 3153 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 56,826 psi | 89% | 3166 fps | 100% |
| Bofors RP5 | <<locked>> | 84% | 54,172 psi | 85% | 3104 fps | 100% |
| Hodgdon H1000 | <<locked>> | 90% | 54,215 psi | 85% | 3110 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 56,072 psi | 88% | 3097 fps | 99.7% |
| Hodgdon H4831 SC | <<locked>> | 84% | 55,100 psi | 86% | 3081 fps | 99.7% |
| Hodgdon Retumbo | <<locked>> | 90% | 56,304 psi | 88% | 3238 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,898 psi | 59% | 2011 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 56,333 psi | 88% | 3074 fps | 99.8% |
| IMR 7828 SSC | <<locked>> | 86% | 56,057 psi | 88% | 3156 fps | 99.9% |
| IMR 8133 Enduron | <<locked>> | 98% | 55,100 psi | 86% | 3156 fps | 100% |
| Lovex S071 | <<locked>> | 90% | 55,999 psi | 88% | 3031 fps | 100% |
| Norma 217 | <<locked>> | 98% | 56,681 psi | 89% | 3179 fps | 100% |
| Norma MRP | <<locked>> | 82% | 54,331 psi | 85% | 3117 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 57,392 psi | 90% | 3179 fps | 100% |
| Ramshot Magnum | <<locked>> | 88% | 55,999 psi | 88% | 3100 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,986 psi | 61% | 2060 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 57,435 psi | 90% | 3225 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 56,492 psi | 89% | 3192 fps | 99.7% |
| Rottweil R 904 | <<locked>> | 82% | 55,216 psi | 87% | 3061 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 82% | 54,360 psi | 85% | 3071 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 51,213 psi | 80% | 3035 fps | 96.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 82% | 53,998 psi | 85% | 3068 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 56,594 psi | 89% | 3048 fps | 99.8% |
| Somchem S385 | <<locked>> | 82% | 54,636 psi | 86% | 3038 fps | 100% |
| Vihtavuori N165 | <<locked>> | 86% | 54,824 psi | 86% | 3031 fps | 100% |
| Vihtavuori N170 | <<locked>> | 90% | 54,027 psi | 85% | 3051 fps | 96.9% |
| Vihtavuori N555 | <<locked>> | 82% | 54,317 psi | 85% | 3041 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 57,435 psi | 90% | 3182 fps | 99.9% |
| Vihtavuori N565 | <<locked>> | 88% | 54,955 psi | 86% | 3117 fps | 99.8% |
| Vihtavuori N568 | <<locked>> | 92% | 56,942 psi | 89% | 3196 fps | 99.5% |
| Vihtavuori N570 | <<locked>> | 92% | 54,360 psi | 85% | 3192 fps | 98% |
| Winchester StaBALL HD | <<locked>> | 86% | 57,087 psi | 89% | 3159 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 84% | 54,476 psi | 85% | 3035 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% | 47,166 psi | 74% | 2887 fps | 100% |
| Accurate 8700 | <<locked>> | 98% | 45,716 psi | 72% | 2953 fps | 95.7% |
| Accurate High Country | <<locked>> | 80% | 52,127 psi | 82% | 3100 fps | 99.7% |
| Accurate MAGPRO | <<locked>> | 80% | 49,429 psi | 77% | 3041 fps | 98.7% |
| ADI AR 2209 | <<locked>> | 80% | 51,372 psi | 81% | 3031 fps | 99.9% |
| ADI AR 2213 | <<locked>> | 80% | 46,528 psi | 73% | 2976 fps | 99% |
| ADI AR 2217 | <<locked>> | 80% | 34,809 psi | 55% | 2703 fps | 96.2% |
| ADI AR 2218 | 108.7 gr | 90% | 42,583 psi | 67% | 2972 fps | 95.1% |
| ADI AR 2225 | <<locked>> | 80% | 32,068 psi | 50% | 2671 fps | 98.2% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 51,517 psi | 81% | 3025 fps | 99.9% |
| Alliant Reloder-19 | <<locked>> | 80% | 51,024 psi | 80% | 3018 fps | 99.9% |
| Alliant Reloder-22 | <<locked>> | 80% | 47,311 psi | 74% | 2976 fps | 99.7% |
| Alliant Reloder-23 | <<locked>> | 80% | 46,166 psi | 72% | 2904 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 40,335 psi | 63% | 2851 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 80% | 52,997 psi | 83% | 3094 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 88% | 44,121 psi | 69% | 2969 fps | 95.8% |
| Alliant Reloder-50 | <<locked>> | 92% | 44,251 psi | 69% | 2959 fps | 95.2% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 44,396 psi | 70% | 2877 fps | 96.2% |
| Bofors RP15 | <<locked>> | 80% | 44,135 psi | 69% | 2913 fps | 99.3% |
| Bofors RP30 | <<locked>> | 80% | 37,579 psi | 59% | 2785 fps | 97.3% |
| Bofors RP5 | <<locked>> | 80% | 47,311 psi | 74% | 2976 fps | 99.7% |
| Hodgdon H1000 | <<locked>> | 80% | 37,826 psi | 59% | 2782 fps | 97.9% |
| Hodgdon H4831 | <<locked>> | 80% | 48,965 psi | 77% | 2972 fps | 99% |
| Hodgdon H4831 SC | <<locked>> | 80% | 48,095 psi | 75% | 2953 fps | 98.8% |
| Hodgdon Retumbo | 91.2 gr | 80% | 39,305 psi | 62% | 2904 fps | 99.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,514 psi | 45% | 1801 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 49,632 psi | 78% | 2956 fps | 99.2% |
| IMR 7828 SSC | <<locked>> | 80% | 45,324 psi | 71% | 2956 fps | 98.8% |
| IMR 8133 Enduron | <<locked>> | 84% | 34,156 psi | 54% | 2710 fps | 95.8% |
| Lovex S071 | <<locked>> | 80% | 40,727 psi | 64% | 2762 fps | 99.9% |
| Norma 217 | <<locked>> | 80% | 30,023 psi | 47% | 2612 fps | 96.2% |
| Norma MRP | <<locked>> | 80% | 50,604 psi | 79% | 3054 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 45,948 psi | 72% | 2976 fps | 99.2% |
| Ramshot Magnum | <<locked>> | 80% | 41,466 psi | 65% | 2841 fps | 99.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,312 psi | 46% | 1847 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 38,856 psi | 61% | 2881 fps | 99.7% |
| ReloadSwiss RS 80 | <<locked>> | 82% | 38,653 psi | 61% | 2835 fps | 96.1% |
| Rottweil R 904 | <<locked>> | 80% | 51,808 psi | 81% | 2999 fps | 99.6% |
| Rottweil R 905 | <<locked>> | 80% | 50,937 psi | 80% | 3015 fps | 99.9% |
| SNPE Vectan SP 13 | <<locked>> | 96% | 44,643 psi | 70% | 2907 fps | 95% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 50,589 psi | 79% | 3009 fps | 99.9% |
| Somchem S361 | <<locked>> | 80% | 52,968 psi | 83% | 2989 fps | 99.5% |
| Somchem S385 | <<locked>> | 80% | 51,155 psi | 80% | 2982 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 44,846 psi | 70% | 2854 fps | 99.7% |
| Vihtavuori N170 | <<locked>> | 86% | 47,253 psi | 74% | 2923 fps | 95.1% |
| Vihtavuori N555 | <<locked>> | 80% | 50,937 psi | 80% | 2986 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 50,053 psi | 78% | 3054 fps | 99.2% |
| Vihtavuori N565 | <<locked>> | 80% | 41,858 psi | 66% | 2861 fps | 97.8% |
| Vihtavuori N568 | <<locked>> | 82% | 39,740 psi | 62% | 2851 fps | 95.9% |
| Vihtavuori N570 | 101.8 gr | 86% | 43,714 psi | 69% | 2979 fps | 95.1% |
| Winchester StaBALL HD | <<locked>> | 80% | 45,513 psi | 71% | 2976 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 47,355 psi | 74% | 2913 fps | 99.7% |
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 52 powders for .30-378 Weath. Mag. loaded with the .308 | 180gr | Sierra GameKing. ADI AR 2218 delivers the highest muzzle velocity at 3,287 fps; across all powders the maximum-charge window runs from 2,011 fps to 3,287 fps. Accurate 8700 gives the best case fill at 100 %, and 52 of the 52 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 180.0 gr projectile in 0.308" calls for a 1:12.5 twist; slower twists will usually not stabilise this weight. Accurate 8700, Hodgdon TrailBoss, ReloadSwiss RS 14 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. ADI AR 2218, Vihtavuori N570, Hodgdon Retumbo rank at the top here: for .30-378 Weath. Mag. with the .308 | 180gr | Sierra GameKing 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.