Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 135gr | IBEX Viper bullet and 62 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% | 54,404 psi | 85% | 3363 fps | 100% |
| Accurate High Country | <<locked>> | 86% | 55,042 psi | 86% | 3514 fps | 98.5% |
| Accurate MAGPRO | <<locked>> | 88% | 56,202 psi | 88% | 3514 fps | 97.7% |
| ADI AR 2209 | <<locked>> | 86% | 54,534 psi | 85% | 3445 fps | 99.1% |
| ADI AR 2213 | <<locked>> | 90% | 56,304 psi | 88% | 3510 fps | 98.6% |
| ADI AR 2217 | <<locked>> | 98% | 55,042 psi | 86% | 3471 fps | 98.8% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 53,737 psi | 84% | 3501 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 82% | 54,520 psi | 85% | 3451 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 54,259 psi | 85% | 3428 fps | 99% |
| Alliant Reloder-22 | <<locked>> | 90% | 57,029 psi | 89% | 3514 fps | 99.5% |
| Alliant Reloder-23 | <<locked>> | 90% | 55,085 psi | 86% | 3428 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 94% | 54,839 psi | 86% | 3491 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 86% | 55,796 psi | 87% | 3520 fps | 100% |
| Alliant Reloder-33ᴾ | <<locked>> | 100% | 57,159 psi | 90% | 3560 fps | 96.2% |
| Baschieri & Pellagri 109 | <<locked>> | 92% | 57,319 psi | 90% | 3451 fps | 96.4% |
| Bofors RP15 | <<locked>> | 92% | 56,434 psi | 88% | 3501 fps | 99.3% |
| Bofors RP30 | <<locked>> | 96% | 55,114 psi | 86% | 3494 fps | 98.9% |
| Bofors RP5 | <<locked>> | 90% | 57,029 psi | 89% | 3514 fps | 99.5% |
| Hodgdon H1000 | <<locked>> | 96% | 56,507 psi | 89% | 3501 fps | 99.4% |
| Hodgdon H4831 | <<locked>> | 88% | 55,912 psi | 88% | 3438 fps | 98% |
| Hodgdon H4831 SC | <<locked>> | 88% | 54,984 psi | 86% | 3419 fps | 97.8% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 55,114 psi | 86% | 3366 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 96% | 57,464 psi | 90% | 3638 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,579 psi | 59% | 2277 fps | 100% |
| IMR 4350 | <<locked>> | 84% | 56,971 psi | 89% | 3422 fps | 99.8% |
| IMR 4831 | <<locked>> | 82% | 54,520 psi | 85% | 3383 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 88% | 56,405 psi | 88% | 3419 fps | 98.2% |
| IMR 7828 SSC | <<locked>> | 90% | 54,665 psi | 86% | 3491 fps | 98.4% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 49,458 psi | 78% | 3399 fps | 97.8% |
| Lovex S065 | <<locked>> | 82% | 57,667 psi | 90% | 3412 fps | 100% |
| Lovex S070 | <<locked>> | 82% | 56,217 psi | 88% | 3409 fps | 99.9% |
| Lovex S071 | <<locked>> | 94% | 55,927 psi | 88% | 3389 fps | 100% |
| Norma 204 | <<locked>> | 82% | 54,621 psi | 86% | 3419 fps | 99% |
| Norma 217ᴾ | <<locked>> | 100% | 50,154 psi | 79% | 3432 fps | 99.5% |
| Norma MRP | <<locked>> | 88% | 57,276 psi | 90% | 3540 fps | 99.9% |
| Norma URP | <<locked>> | 82% | 55,753 psi | 87% | 3428 fps | 100% |
| Ramshot Grand | <<locked>> | 90% | 55,651 psi | 87% | 3510 fps | 98.9% |
| Ramshot Hunter | <<locked>> | 82% | 54,650 psi | 86% | 3428 fps | 100% |
| Ramshot Magnum | <<locked>> | 92% | 54,694 psi | 86% | 3438 fps | 99.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,609 psi | 61% | 2333 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 82% | 55,956 psi | 88% | 3497 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 54,824 psi | 86% | 3563 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 96% | 54,549 psi | 85% | 3504 fps | 97.7% |
| Rottweil R 904 | <<locked>> | 86% | 55,259 psi | 87% | 3406 fps | 98.4% |
| Rottweil R 905 | <<locked>> | 88% | 57,667 psi | 90% | 3488 fps | 99.5% |
| Shooters World Long Rifle | <<locked>> | 82% | 57,667 psi | 90% | 3412 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 56,217 psi | 88% | 3409 fps | 99.9% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 56,724 psi | 89% | 3353 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 57,232 psi | 90% | 3481 fps | 99.4% |
| Somchem S361 | <<locked>> | 86% | 57,188 psi | 90% | 3392 fps | 98.2% |
| Somchem S365 | <<locked>> | 84% | 56,942 psi | 89% | 3435 fps | 100% |
| Somchem S385 | <<locked>> | 86% | 54,897 psi | 86% | 3396 fps | 99.6% |
| Vihtavuori N160 | <<locked>> | 82% | 57,217 psi | 90% | 3415 fps | 100% |
| Vihtavuori N165 | <<locked>> | 90% | 54,375 psi | 85% | 3366 fps | 99.4% |
| Vihtavuori N550 | <<locked>> | 82% | 56,753 psi | 89% | 3425 fps | 100% |
| Vihtavuori N555 | <<locked>> | 88% | 57,464 psi | 90% | 3465 fps | 100% |
| Vihtavuori N560 | <<locked>> | 88% | 56,623 psi | 89% | 3527 fps | 98.3% |
| Vihtavuori N565 | <<locked>> | 92% | 54,201 psi | 85% | 3448 fps | 98.1% |
| Vihtavuori N568 | <<locked>> | 96% | 54,926 psi | 86% | 3507 fps | 97.2% |
| Winchester 6.5 StaBALL | <<locked>> | 82% | 56,637 psi | 89% | 3353 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 90% | 54,273 psi | 85% | 3520 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 88% | 54,288 psi | 85% | 3376 fps | 99.1% |
Start Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 41,989 psi | 66% | 3114 fps | 98.7% |
| Accurate High Country | <<locked>> | 80% | 45,049 psi | 71% | 3301 fps | 96.2% |
| Accurate MAGPRO | <<locked>> | 84% | 48,849 psi | 77% | 3366 fps | 95.9% |
| ADI AR 2209 | <<locked>> | 80% | 44,744 psi | 70% | 3238 fps | 97.1% |
| ADI AR 2213 | <<locked>> | 82% | 43,192 psi | 68% | 3232 fps | 95.4% |
| ADI AR 2217 | <<locked>> | 90% | 42,279 psi | 66% | 3192 fps | 95.5% |
| ADI AR 2225 | <<locked>> | 86% | 34,229 psi | 54% | 3018 fps | 95.6% |
| Alliant Reloder-16 | <<locked>> | 80% | 51,111 psi | 80% | 3392 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 44,875 psi | 70% | 3235 fps | 97.2% |
| Alliant Reloder-22 | <<locked>> | 80% | 41,162 psi | 65% | 3179 fps | 96.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 39,987 psi | 63% | 3136 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 34,751 psi | 54% | 3035 fps | 97.5% |
| Alliant Reloder-26 | <<locked>> | 80% | 44,831 psi | 70% | 3314 fps | 99.9% |
| Alliant Reloder-33 | <<locked>> | 98% | 53,171 psi | 83% | 3484 fps | 95.2% |
| Baschieri & Pellagri 109 | <<locked>> | 90% | 53,896 psi | 84% | 3386 fps | 95.6% |
| Bofors RP15 | <<locked>> | 80% | 38,406 psi | 60% | 3100 fps | 95% |
| Bofors RP30 | <<locked>> | 88% | 42,380 psi | 66% | 3222 fps | 95.9% |
| Bofors RP5 | <<locked>> | 80% | 41,162 psi | 65% | 3179 fps | 96.3% |
| Hodgdon H1000 | <<locked>> | 86% | 40,437 psi | 63% | 3150 fps | 95.5% |
| Hodgdon H4831 | <<locked>> | 82% | 45,890 psi | 72% | 3235 fps | 95.6% |
| Hodgdon H4831 SC | <<locked>> | 82% | 45,078 psi | 71% | 3215 fps | 95.3% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 48,544 psi | 76% | 3255 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 84% | 38,725 psi | 61% | 3205 fps | 96.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,282 psi | 44% | 2047 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 50,357 psi | 79% | 3301 fps | 99.1% |
| IMR 4831 | <<locked>> | 80% | 51,111 psi | 80% | 3320 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 44,092 psi | 69% | 3163 fps | 95.3% |
| IMR 7828 SSC | <<locked>> | 82% | 41,829 psi | 66% | 3205 fps | 95% |
| IMR 8133 Enduron | <<locked>> | 94% | 40,683 psi | 64% | 3196 fps | 95.1% |
| Lovex S065 | <<locked>> | 80% | 54,360 psi | 85% | 3356 fps | 100% |
| Lovex S070 | <<locked>> | 80% | 52,779 psi | 83% | 3346 fps | 99.7% |
| Lovex S071 | <<locked>> | 80% | 36,506 psi | 57% | 2979 fps | 97.3% |
| Norma 204 | <<locked>> | 80% | 51,169 psi | 80% | 3353 fps | 98.4% |
| Norma 217 | <<locked>> | 90% | 36,056 psi | 56% | 3097 fps | 95.7% |
| Norma MRP | <<locked>> | 80% | 43,555 psi | 68% | 3264 fps | 98.2% |
| Norma URP | <<locked>> | 80% | 52,286 psi | 82% | 3366 fps | 100% |
| Ramshot Grand | <<locked>> | 82% | 41,887 psi | 66% | 3219 fps | 95.5% |
| Ramshot Hunter | <<locked>> | 80% | 51,285 psi | 80% | 3363 fps | 99.8% |
| Ramshot Magnum | <<locked>> | 80% | 35,491 psi | 56% | 3012 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,022 psi | 45% | 2096 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 52,156 psi | 82% | 3428 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 82% | 35,795 psi | 56% | 3104 fps | 96.2% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 46,992 psi | 74% | 3353 fps | 95.8% |
| Rottweil R 904 | <<locked>> | 80% | 45,832 psi | 72% | 3212 fps | 96.4% |
| Rottweil R 905 | <<locked>> | 80% | 44,541 psi | 70% | 3225 fps | 97.3% |
| Shooters World Long Rifle | <<locked>> | 80% | 54,360 psi | 85% | 3356 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 52,779 psi | 83% | 3346 fps | 99.7% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 53,229 psi | 83% | 3294 fps | 99.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 44,193 psi | 69% | 3219 fps | 97.2% |
| Somchem S361 | <<locked>> | 80% | 46,992 psi | 74% | 3196 fps | 96% |
| Somchem S365 | <<locked>> | 80% | 49,966 psi | 78% | 3317 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 45,368 psi | 71% | 3205 fps | 98.2% |
| Vihtavuori N160 | <<locked>> | 80% | 53,635 psi | 84% | 3356 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 39,552 psi | 62% | 3054 fps | 96.4% |
| Vihtavuori N550 | <<locked>> | 80% | 53,272 psi | 83% | 3363 fps | 100% |
| Vihtavuori N555 | <<locked>> | 80% | 44,802 psi | 70% | 3232 fps | 100% |
| Vihtavuori N560 | <<locked>> | 82% | 46,195 psi | 72% | 3314 fps | 95.8% |
| Vihtavuori N565 | <<locked>> | 86% | 44,614 psi | 70% | 3248 fps | 95.7% |
| Vihtavuori N568 | <<locked>> | 92% | 47,848 psi | 75% | 3363 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 52,968 psi | 83% | 3294 fps | 100% |
| Winchester StaBALL HD | <<locked>> | 80% | 37,246 psi | 58% | 3182 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 41,626 psi | 65% | 3114 fps | 96.4% |
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 62 powders for .30-378 Weath. Mag. loaded with the .308 | 135gr | IBEX Viper. Hodgdon Retumbo delivers the highest muzzle velocity at 3,638 fps; across all powders the maximum-charge window runs from 2,277 fps to 3,638 fps. ADI AR 2225 gives the best case fill at 100 %, and 62 of the 62 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 135.0 gr projectile in 0.308" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. ADI AR 2225, Alliant Reloder-33, Hodgdon TrailBoss 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.