Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 155.5gr | Berger Fullbore Target bullet and 57 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.
A valid access license is required to use the Personalized Load Calculator.
You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 88% | 55,709 psi | 87% | 3219 fps | 100% |
| Accurate High Country | <<locked>> | 86% | 57,580 psi | 90% | 3389 fps | 99.6% |
| Accurate MAGPRO | <<locked>> | 86% | 54,650 psi | 86% | 3320 fps | 98.5% |
| ADI AR 2209 | <<locked>> | 86% | 56,869 psi | 89% | 3314 fps | 99.9% |
| ADI AR 2213 | <<locked>> | 88% | 55,317 psi | 87% | 3323 fps | 99.3% |
| ADI AR 2217 | <<locked>> | 96% | 53,998 psi | 85% | 3291 fps | 99.5% |
| ADI AR 2218ᴾ | <<locked>> | 100% | 54,723 psi | 86% | 3402 fps | 97.2% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 56,811 psi | 89% | 3379 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 82% | 57,014 psi | 89% | 3307 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 56,420 psi | 88% | 3301 fps | 99.8% |
| Alliant Reloder-22 | <<locked>> | 88% | 55,796 psi | 87% | 3320 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 90% | 57,638 psi | 90% | 3284 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 92% | 54,099 psi | 85% | 3297 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 84% | 54,317 psi | 85% | 3310 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 98% | 56,260 psi | 88% | 3383 fps | 97.4% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 56,188 psi | 88% | 3278 fps | 97.6% |
| Bofors RP15 | <<locked>> | 90% | 55,187 psi | 86% | 3307 fps | 99.8% |
| Bofors RP30 | <<locked>> | 94% | 53,925 psi | 85% | 3304 fps | 99.5% |
| Bofors RP5 | <<locked>> | 88% | 55,796 psi | 87% | 3320 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 94% | 55,579 psi | 87% | 3317 fps | 99.8% |
| Hodgdon H4831 | <<locked>> | 86% | 54,418 psi | 85% | 3248 fps | 98.8% |
| Hodgdon H4831 SC | <<locked>> | 88% | 57,246 psi | 90% | 3297 fps | 99.2% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 57,174 psi | 90% | 3219 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 94% | 56,942 psi | 89% | 3448 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,579 psi | 59% | 2146 fps | 100% |
| IMR 4350 | <<locked>> | 82% | 55,477 psi | 87% | 3228 fps | 100% |
| IMR 4831 | <<locked>> | 82% | 56,159 psi | 88% | 3232 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 86% | 54,969 psi | 86% | 3232 fps | 99% |
| IMR 7828 SSC | <<locked>> | 90% | 57,522 psi | 90% | 3369 fps | 99.6% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 52,011 psi | 82% | 3281 fps | 99.2% |
| Lovex S070 | <<locked>> | 82% | 57,725 psi | 90% | 3261 fps | 100% |
| Lovex S071 | <<locked>> | 94% | 57,377 psi | 90% | 3241 fps | 100% |
| Norma 204 | <<locked>> | 82% | 56,724 psi | 89% | 3291 fps | 99.8% |
| Norma 217ᴾ | <<locked>> | 100% | 52,982 psi | 83% | 3310 fps | 100% |
| Norma MRP | <<locked>> | 86% | 55,912 psi | 88% | 3337 fps | 100% |
| Norma URP | <<locked>> | 82% | 57,711 psi | 90% | 3281 fps | 100% |
| Ramshot Grand | <<locked>> | 88% | 54,795 psi | 86% | 3323 fps | 99.5% |
| Ramshot Hunter | <<locked>> | 82% | 56,710 psi | 89% | 3287 fps | 100% |
| Ramshot Magnum | <<locked>> | 92% | 57,653 psi | 90% | 3317 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,479 psi | 60% | 2192 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 53,838 psi | 84% | 3366 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 94% | 53,417 psi | 84% | 3317 fps | 98.6% |
| Rottweil R 904 | <<locked>> | 86% | 57,522 psi | 90% | 3281 fps | 99.5% |
| Rottweil R 905 | <<locked>> | 86% | 56,202 psi | 88% | 3291 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 82% | 57,725 psi | 90% | 3261 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 55,825 psi | 87% | 3284 fps | 99.8% |
| Somchem S361 | <<locked>> | 84% | 55,317 psi | 87% | 3202 fps | 98.9% |
| Somchem S365 | <<locked>> | 82% | 55,492 psi | 87% | 3225 fps | 100% |
| Somchem S385 | <<locked>> | 86% | 56,594 psi | 89% | 3258 fps | 100% |
| Vihtavuori N165 | <<locked>> | 90% | 56,594 psi | 89% | 3241 fps | 100% |
| Vihtavuori N555 | <<locked>> | 86% | 55,666 psi | 87% | 3255 fps | 100% |
| Vihtavuori N560 | <<locked>> | 86% | 55,347 psi | 87% | 3333 fps | 99% |
| Vihtavuori N565 | <<locked>> | 92% | 56,333 psi | 88% | 3323 fps | 99.3% |
| Vihtavuori N568 | <<locked>> | 94% | 54,027 psi | 85% | 3323 fps | 98.2% |
| Vihtavuori N570 | <<locked>> | 96% | 55,245 psi | 87% | 3392 fps | 96.8% |
| Winchester StaBALL HD | <<locked>> | 90% | 57,696 psi | 90% | 3379 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 88% | 56,536 psi | 89% | 3255 fps | 99.9% |
Start Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 42,395 psi | 66% | 2969 fps | 99.5% |
| Accurate High Country | <<locked>> | 80% | 46,572 psi | 73% | 3173 fps | 97.9% |
| Accurate MAGPRO | <<locked>> | 80% | 44,092 psi | 69% | 3104 fps | 96.1% |
| ADI AR 2209 | <<locked>> | 80% | 46,369 psi | 73% | 3114 fps | 98.7% |
| ADI AR 2213 | <<locked>> | 80% | 41,684 psi | 65% | 3041 fps | 96.5% |
| ADI AR 2217 | <<locked>> | 86% | 38,203 psi | 60% | 2946 fps | 95.7% |
| ADI AR 2218 | <<locked>> | 98% | 50,807 psi | 80% | 3317 fps | 96.1% |
| ADI AR 2225 | <<locked>> | 82% | 30,472 psi | 48% | 2769 fps | 95.4% |
| Alliant Reloder-16 | <<locked>> | 80% | 53,374 psi | 84% | 3248 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 46,325 psi | 73% | 3107 fps | 98.7% |
| Alliant Reloder-22 | <<locked>> | 80% | 42,395 psi | 66% | 3051 fps | 97.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 41,191 psi | 65% | 2995 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 35,520 psi | 56% | 2910 fps | 99% |
| Alliant Reloder-26 | <<locked>> | 80% | 46,615 psi | 73% | 3173 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 48,327 psi | 76% | 3225 fps | 95.4% |
| Baschieri & Pellagri 109 | <<locked>> | 84% | 46,253 psi | 72% | 3081 fps | 95% |
| Bofors RP15 | <<locked>> | 80% | 39,421 psi | 62% | 2976 fps | 97% |
| Bofors RP30 | <<locked>> | 84% | 38,174 psi | 60% | 2963 fps | 95.8% |
| Bofors RP5 | <<locked>> | 80% | 42,395 psi | 66% | 3051 fps | 97.9% |
| Hodgdon H1000 | <<locked>> | 82% | 36,216 psi | 57% | 2897 fps | 95.6% |
| Hodgdon H4831 | <<locked>> | 80% | 44,324 psi | 69% | 3045 fps | 96.7% |
| Hodgdon H4831 SC | <<locked>> | 80% | 43,511 psi | 68% | 3028 fps | 96.4% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 50,169 psi | 79% | 3107 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 80% | 34,693 psi | 54% | 2940 fps | 96.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,152 psi | 44% | 1923 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 51,996 psi | 81% | 3166 fps | 99.9% |
| IMR 4831 | <<locked>> | 80% | 52,562 psi | 82% | 3173 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 45,324 psi | 71% | 3038 fps | 97.1% |
| IMR 7828 SSC | <<locked>> | 80% | 40,379 psi | 63% | 3018 fps | 96.1% |
| IMR 8133 Enduron | <<locked>> | 90% | 36,753 psi | 58% | 2943 fps | 95.1% |
| Lovex S070 | <<locked>> | 80% | 54,085 psi | 85% | 3202 fps | 100% |
| Lovex S071 | <<locked>> | 80% | 36,521 psi | 57% | 2835 fps | 98.5% |
| Norma 204 | <<locked>> | 80% | 53,040 psi | 83% | 3225 fps | 99.5% |
| Norma 217 | <<locked>> | 86% | 32,213 psi | 50% | 2835 fps | 95.5% |
| Norma MRP | <<locked>> | 80% | 45,107 psi | 71% | 3130 fps | 99.4% |
| Norma URP | <<locked>> | 80% | 53,983 psi | 85% | 3222 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 40,422 psi | 63% | 3031 fps | 96.6% |
| Ramshot Hunter | <<locked>> | 80% | 53,098 psi | 83% | 3225 fps | 100% |
| Ramshot Magnum | <<locked>> | 80% | 36,434 psi | 57% | 2894 fps | 97.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,877 psi | 45% | 1969 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 34,040 psi | 53% | 2910 fps | 97.1% |
| ReloadSwiss RS 80 | <<locked>> | 88% | 42,351 psi | 66% | 3087 fps | 95.7% |
| Rottweil R 904 | <<locked>> | 80% | 47,181 psi | 74% | 3087 fps | 98% |
| Rottweil R 905 | <<locked>> | 80% | 45,890 psi | 72% | 3094 fps | 98.7% |
| Shooters World SW4350 | <<locked>> | 80% | 54,085 psi | 85% | 3202 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 45,542 psi | 71% | 3091 fps | 98.7% |
| Somchem S361 | <<locked>> | 80% | 48,385 psi | 76% | 3074 fps | 97.7% |
| Somchem S365 | <<locked>> | 80% | 51,750 psi | 81% | 3166 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 46,369 psi | 73% | 3071 fps | 99.3% |
| Vihtavuori N165 | <<locked>> | 80% | 40,451 psi | 63% | 2930 fps | 98% |
| Vihtavuori N555 | <<locked>> | 80% | 45,745 psi | 72% | 3084 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 44,817 psi | 70% | 3123 fps | 96.9% |
| Vihtavuori N565 | <<locked>> | 82% | 39,856 psi | 62% | 2979 fps | 95.6% |
| Vihtavuori N568 | <<locked>> | 88% | 43,366 psi | 68% | 3104 fps | 95.4% |
| Vihtavuori N570 | <<locked>> | 94% | 51,300 psi | 80% | 3314 fps | 95.8% |
| Winchester StaBALL HD | <<locked>> | 80% | 39,189 psi | 61% | 3045 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 42,757 psi | 67% | 2989 fps | 98% |
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 65 powders for .30-378 Weath. Mag. loaded with the .308 | 155.5gr | Berger Fullbore Target. Hodgdon Retumbo delivers the highest muzzle velocity at 3,448 fps; across all powders the maximum-charge window runs from 2,146 fps to 3,448 fps. Accurate 8700 gives the best case fill at 100 %, and 65 of the 65 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 155.5 gr projectile in 0.308" calls for a 1:12.5 twist; slower twists will usually not stabilise this weight. Accurate 8700, ADI AR 2218, ADI AR 2225 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. As outliers, Accurate 8700, IMR 7977 Enduron, Lovex D100 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.