Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 165gr | Barnes MRX BT bullet and 58 powders. The key underlying parameters are shown in the table above.
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>> | 88% | 55,666 psi | 87% | 3143 fps | 100% |
| Accurate High Country | <<locked>> | 86% | 57,740 psi | 90% | 3317 fps | 99.8% |
| Accurate MAGPRO | <<locked>> | 86% | 54,810 psi | 86% | 3251 fps | 98.9% |
| ADI AR 2209 | <<locked>> | 86% | 57,217 psi | 90% | 3245 fps | 100% |
| ADI AR 2213 | <<locked>> | 88% | 55,608 psi | 87% | 3255 fps | 99.6% |
| ADI AR 2217 | <<locked>> | 96% | 54,302 psi | 85% | 3225 fps | 99.7% |
| ADI AR 2218ᴾ | <<locked>> | 100% | 54,969 psi | 86% | 3343 fps | 97.9% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 57,174 psi | 90% | 3310 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 82% | 57,203 psi | 90% | 3228 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 56,681 psi | 89% | 3228 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 88% | 55,956 psi | 88% | 3248 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 88% | 54,027 psi | 85% | 3150 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 92% | 54,433 psi | 85% | 3225 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 84% | 54,462 psi | 85% | 3238 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 98% | 56,478 psi | 89% | 3317 fps | 97.9% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 51,750 psi | 81% | 3219 fps | 96.4% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 56,492 psi | 89% | 3212 fps | 98% |
| Bofors RP15 | <<locked>> | 90% | 55,317 psi | 87% | 3235 fps | 99.9% |
| Bofors RP30 | <<locked>> | 94% | 54,143 psi | 85% | 3235 fps | 99.7% |
| Bofors RP5 | <<locked>> | 88% | 55,956 psi | 88% | 3248 fps | 100% |
| Hodgdon H1000 | <<locked>> | 94% | 55,912 psi | 88% | 3251 fps | 100% |
| Hodgdon H4831 | <<locked>> | 86% | 54,737 psi | 86% | 3182 fps | 99.1% |
| Hodgdon H4831 SC | <<locked>> | 88% | 57,479 psi | 90% | 3228 fps | 99.4% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 57,276 psi | 90% | 3143 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 94% | 57,348 psi | 90% | 3379 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,550 psi | 59% | 2083 fps | 100% |
| IMR 4350 | <<locked>> | 82% | 55,622 psi | 87% | 3156 fps | 100% |
| IMR 4831 | <<locked>> | 82% | 56,130 psi | 88% | 3156 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 86% | 55,187 psi | 86% | 3163 fps | 99.3% |
| IMR 7828 SSC | <<locked>> | 88% | 53,998 psi | 85% | 3232 fps | 99.5% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 51,996 psi | 81% | 3212 fps | 99.5% |
| Lovex S070 | <<locked>> | 82% | 57,682 psi | 90% | 3186 fps | 100% |
| Lovex S071 | <<locked>> | 94% | 57,392 psi | 90% | 3169 fps | 100% |
| Norma 204 | <<locked>> | 82% | 56,956 psi | 89% | 3219 fps | 99.9% |
| Norma 217ᴾ | <<locked>> | 100% | 53,200 psi | 83% | 3241 fps | 100% |
| Norma MRP | <<locked>> | 86% | 56,086 psi | 88% | 3268 fps | 100% |
| Ramshot Grand | <<locked>> | 88% | 55,172 psi | 86% | 3258 fps | 99.7% |
| Ramshot Hunter | <<locked>> | 82% | 56,898 psi | 89% | 3215 fps | 100% |
| Ramshot Magnum | <<locked>> | 90% | 53,606 psi | 84% | 3176 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,435 psi | 60% | 2129 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 54,302 psi | 85% | 3297 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 94% | 53,548 psi | 84% | 3255 fps | 99% |
| Rottweil R 904 | <<locked>> | 84% | 54,085 psi | 85% | 3150 fps | 99.4% |
| Rottweil R 905 | <<locked>> | 86% | 56,420 psi | 88% | 3222 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 57,682 psi | 90% | 3186 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 56,028 psi | 88% | 3215 fps | 100% |
| Somchem S361 | <<locked>> | 84% | 55,434 psi | 87% | 3133 fps | 99.2% |
| Somchem S365 | <<locked>> | 82% | 55,492 psi | 87% | 3150 fps | 100% |
| Somchem S385 | <<locked>> | 86% | 56,739 psi | 89% | 3186 fps | 100% |
| Vihtavuori N165 | <<locked>> | 90% | 56,768 psi | 89% | 3173 fps | 100% |
| Vihtavuori N170 | <<locked>> | 94% | 55,840 psi | 88% | 3182 fps | 96.2% |
| Vihtavuori N555 | <<locked>> | 86% | 55,651 psi | 87% | 3179 fps | 100% |
| Vihtavuori N560 | <<locked>> | 86% | 55,564 psi | 87% | 3268 fps | 99.4% |
| Vihtavuori N565 | <<locked>> | 92% | 56,362 psi | 88% | 3251 fps | 99.6% |
| Vihtavuori N568 | <<locked>> | 94% | 54,143 psi | 85% | 3258 fps | 98.6% |
| Vihtavuori N570 | <<locked>> | 96% | 55,448 psi | 87% | 3327 fps | 97.4% |
| Winchester StaBALL HD | <<locked>> | 88% | 53,838 psi | 84% | 3241 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 88% | 56,724 psi | 89% | 3182 fps | 100% |
Start Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 42,076 psi | 66% | 2897 fps | 99.7% |
| Accurate High Country | <<locked>> | 80% | 46,543 psi | 73% | 3104 fps | 98.3% |
| Accurate MAGPRO | <<locked>> | 80% | 43,947 psi | 69% | 3031 fps | 96.6% |
| ADI AR 2209 | <<locked>> | 80% | 46,499 psi | 73% | 3048 fps | 99.1% |
| ADI AR 2213 | <<locked>> | 80% | 41,785 psi | 65% | 2979 fps | 97.1% |
| ADI AR 2217 | <<locked>> | 84% | 35,563 psi | 56% | 2818 fps | 95.3% |
| ADI AR 2218 | <<locked>> | 96% | 47,137 psi | 74% | 3173 fps | 95.5% |
| ADI AR 2225 | <<locked>> | 82% | 30,168 psi | 47% | 2700 fps | 95.9% |
| Alliant Reloder-16 | <<locked>> | 80% | 53,606 psi | 84% | 3173 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 46,412 psi | 73% | 3038 fps | 99% |
| Alliant Reloder-22 | <<locked>> | 80% | 42,409 psi | 66% | 2982 fps | 98.4% |
| Alliant Reloder-23 | <<locked>> | 80% | 41,147 psi | 64% | 2923 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 35,433 psi | 56% | 2844 fps | 99.3% |
| Alliant Reloder-26 | <<locked>> | 80% | 46,659 psi | 73% | 3100 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 48,414 psi | 76% | 3163 fps | 96% |
| Alliant Reloder-50 | <<locked>> | 98% | 47,877 psi | 75% | 3140 fps | 95.2% |
| Baschieri & Pellagri 109 | <<locked>> | 84% | 46,296 psi | 73% | 3015 fps | 95.6% |
| Bofors RP15 | <<locked>> | 80% | 39,334 psi | 62% | 2910 fps | 97.4% |
| Bofors RP30 | <<locked>> | 82% | 35,317 psi | 55% | 2825 fps | 95.3% |
| Bofors RP5 | <<locked>> | 80% | 42,409 psi | 66% | 2982 fps | 98.4% |
| Hodgdon H1000 | <<locked>> | 80% | 33,620 psi | 53% | 2766 fps | 95% |
| Hodgdon H4831 | <<locked>> | 80% | 44,425 psi | 70% | 2982 fps | 97.2% |
| Hodgdon H4831 SC | <<locked>> | 80% | 43,584 psi | 68% | 2966 fps | 97% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 50,212 psi | 79% | 3031 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 80% | 34,621 psi | 54% | 2881 fps | 96.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,181 psi | 44% | 1867 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 52,156 psi | 82% | 3097 fps | 100% |
| IMR 4831 | <<locked>> | 80% | 52,562 psi | 82% | 3100 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 45,382 psi | 71% | 2972 fps | 97.6% |
| IMR 7828 SSC | <<locked>> | 80% | 40,437 psi | 63% | 2956 fps | 96.7% |
| IMR 8133 Enduron | <<locked>> | 90% | 36,550 psi | 57% | 2874 fps | 95.6% |
| Lovex S070 | <<locked>> | 80% | 54,114 psi | 85% | 3130 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 36,027 psi | 56% | 2759 fps | 98.7% |
| Norma 204 | <<locked>> | 80% | 53,156 psi | 83% | 3153 fps | 99.7% |
| Norma 217 | <<locked>> | 86% | 31,937 psi | 50% | 2766 fps | 96% |
| Norma MRP | <<locked>> | 80% | 45,078 psi | 71% | 3061 fps | 99.6% |
| Ramshot Grand | <<locked>> | 80% | 40,451 psi | 63% | 2966 fps | 97.2% |
| Ramshot Hunter | <<locked>> | 80% | 53,200 psi | 83% | 3150 fps | 100% |
| Ramshot Magnum | <<locked>> | 80% | 36,361 psi | 57% | 2828 fps | 97.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,776 psi | 45% | 1909 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 33,866 psi | 53% | 2848 fps | 97.7% |
| ReloadSwiss RS 80 | <<locked>> | 86% | 39,088 psi | 61% | 2946 fps | 95.1% |
| Rottweil R 904 | <<locked>> | 80% | 47,282 psi | 74% | 3018 fps | 98.4% |
| Rottweil R 905 | <<locked>> | 80% | 45,905 psi | 72% | 3028 fps | 99.1% |
| Shooters World SW4350 | <<locked>> | 80% | 54,114 psi | 85% | 3130 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 45,556 psi | 71% | 3022 fps | 99% |
| Somchem S361 | <<locked>> | 80% | 48,298 psi | 76% | 3005 fps | 98.1% |
| Somchem S365 | <<locked>> | 80% | 51,837 psi | 81% | 3094 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 46,340 psi | 73% | 2999 fps | 99.5% |
| Vihtavuori N165 | <<locked>> | 80% | 40,408 psi | 63% | 2864 fps | 98.4% |
| Vihtavuori N170 | <<locked>> | 92% | 52,156 psi | 82% | 3117 fps | 95.3% |
| Vihtavuori N555 | <<locked>> | 80% | 45,585 psi | 71% | 3005 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 44,831 psi | 70% | 3054 fps | 97.4% |
| Vihtavuori N565 | <<locked>> | 80% | 36,854 psi | 58% | 2844 fps | 95.1% |
| Vihtavuori N568 | <<locked>> | 88% | 43,424 psi | 68% | 3041 fps | 96.1% |
| Vihtavuori N570 | <<locked>> | 92% | 47,732 psi | 75% | 3173 fps | 95.3% |
| Winchester StaBALL HD | <<locked>> | 80% | 39,189 psi | 61% | 2972 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 42,627 psi | 67% | 2920 fps | 98.4% |
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 58 powders for .30-378 Weath. Mag. loaded with the .308 | 165gr | Barnes MRX BT. Hodgdon Retumbo delivers the highest muzzle velocity at 3,379 fps; across all powders the maximum-charge window runs from 2,083 fps to 3,379 fps. ADI AR 2218 gives the best case fill at 100 %, and 58 of the 58 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 165.0 gr projectile in 0.308" calls for a 1:12.0 twist; slower twists will usually not stabilise this weight. ADI AR 2218, ADI AR 2225, Alliant Reloder-50 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. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.