Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 170gr | Speer Deep Curl Flat Points bullet and 50 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>> | 86% | 55,970 psi | 88% | 3107 fps | 100% |
| Accurate High Country | <<locked>> | 82% | 54,012 psi | 85% | 3205 fps | 99.7% |
| Accurate MAGPRO | <<locked>> | 84% | 55,042 psi | 86% | 3215 fps | 99.2% |
| ADI AR 2209 | <<locked>> | 84% | 56,942 psi | 89% | 3196 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 55,637 psi | 87% | 3212 fps | 99.8% |
| ADI AR 2217 | <<locked>> | 94% | 54,708 psi | 86% | 3189 fps | 99.9% |
| ADI AR 2218 | <<locked>> | 98% | 55,347 psi | 87% | 3310 fps | 98.3% |
| ADI AR 2225 | <<locked>> | 96% | 54,099 psi | 85% | 3215 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 56,695 psi | 89% | 3189 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 86% | 56,202 psi | 88% | 3209 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 54,462 psi | 85% | 3114 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 55,013 psi | 86% | 3192 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 55,013 psi | 86% | 3199 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 96% | 57,334 psi | 90% | 3291 fps | 98.4% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 57,305 psi | 90% | 3281 fps | 98% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 56,115 psi | 88% | 3169 fps | 98.3% |
| Bofors RP15 | <<locked>> | 88% | 55,579 psi | 87% | 3196 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 54,795 psi | 86% | 3202 fps | 99.9% |
| Bofors RP5 | <<locked>> | 86% | 56,202 psi | 88% | 3209 fps | 100% |
| Hodgdon H1000 | <<locked>> | 92% | 56,333 psi | 88% | 3215 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 54,520 psi | 85% | 3140 fps | 99.4% |
| Hodgdon H4831 SC | <<locked>> | 86% | 57,290 psi | 90% | 3186 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% | 37,811 psi | 59% | 2064 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 54,824 psi | 86% | 3117 fps | 99.5% |
| IMR 7828 SSC | <<locked>> | 86% | 54,259 psi | 85% | 3196 fps | 99.7% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 56,956 psi | 89% | 3258 fps | 100% |
| Lovex S071 | <<locked>> | 90% | 54,360 psi | 85% | 3081 fps | 100% |
| Norma 217 | <<locked>> | 98% | 54,491 psi | 85% | 3219 fps | 100% |
| Norma MRP | <<locked>> | 84% | 56,304 psi | 88% | 3225 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 55,492 psi | 87% | 3222 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 88% | 53,940 psi | 85% | 3140 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,870 psi | 61% | 2116 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 55,114 psi | 86% | 3264 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 54,462 psi | 85% | 3225 fps | 99.3% |
| Rottweil R 904 | <<locked>> | 84% | 57,377 psi | 90% | 3166 fps | 99.8% |
| Rottweil R 905 | <<locked>> | 84% | 56,420 psi | 88% | 3179 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 56,043 psi | 88% | 3173 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 55,114 psi | 86% | 3091 fps | 99.4% |
| Somchem S385 | <<locked>> | 84% | 56,753 psi | 89% | 3146 fps | 100% |
| Vihtavuori N165 | <<locked>> | 88% | 56,739 psi | 89% | 3130 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 56,159 psi | 88% | 3153 fps | 96.8% |
| Vihtavuori N555 | <<locked>> | 84% | 56,231 psi | 88% | 3143 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 55,680 psi | 87% | 3225 fps | 99.6% |
| Vihtavuori N565 | <<locked>> | 90% | 56,942 psi | 89% | 3219 fps | 99.8% |
| Vihtavuori N568 | <<locked>> | 92% | 54,911 psi | 86% | 3228 fps | 99% |
| Vihtavuori N570 | <<locked>> | 94% | 56,260 psi | 88% | 3297 fps | 97.9% |
| Winchester StaBALL HD | <<locked>> | 86% | 54,911 psi | 86% | 3205 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 56,594 psi | 89% | 3140 fps | 100% |
Start Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 80% | 45,803 psi | 72% | 2933 fps | 100% |
| Accurate High Country | <<locked>> | 80% | 50,473 psi | 79% | 3140 fps | 99.3% |
| Accurate MAGPRO | <<locked>> | 80% | 47,703 psi | 75% | 3074 fps | 97.9% |
| ADI AR 2209 | <<locked>> | 80% | 49,850 psi | 78% | 3074 fps | 99.7% |
| ADI AR 2213 | <<locked>> | 80% | 45,121 psi | 71% | 3012 fps | 98.3% |
| ADI AR 2217 | <<locked>> | 82% | 35,984 psi | 56% | 2792 fps | 96% |
| ADI AR 2218 | <<locked>> | 92% | 44,324 psi | 69% | 3074 fps | 95% |
| ADI AR 2225 | <<locked>> | 80% | 30,995 psi | 49% | 2694 fps | 97% |
| Alliant Reloder-19 | <<locked>> | 80% | 49,705 psi | 78% | 3064 fps | 99.7% |
| Alliant Reloder-22 | <<locked>> | 80% | 45,890 psi | 72% | 3018 fps | 99.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 44,643 psi | 70% | 2946 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 38,812 psi | 61% | 2884 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 80% | 50,966 psi | 80% | 3133 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 90% | 45,745 psi | 72% | 3068 fps | 95.7% |
| Alliant Reloder-50 | <<locked>> | 94% | 45,730 psi | 72% | 3054 fps | 95% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 43,250 psi | 68% | 2913 fps | 95.2% |
| Bofors RP15 | <<locked>> | 80% | 42,699 psi | 67% | 2949 fps | 98.6% |
| Bofors RP30 | <<locked>> | 80% | 36,274 psi | 57% | 2812 fps | 96.2% |
| Bofors RP5 | <<locked>> | 80% | 45,890 psi | 72% | 3018 fps | 99.3% |
| Hodgdon H1000 | <<locked>> | 80% | 36,608 psi | 57% | 2812 fps | 96.9% |
| Hodgdon H4831 | <<locked>> | 80% | 47,630 psi | 75% | 3012 fps | 98.3% |
| Hodgdon H4831 SC | <<locked>> | 80% | 46,789 psi | 73% | 2995 fps | 98.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 53,664 psi | 84% | 3045 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 80% | 37,942 psi | 59% | 2933 fps | 98.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,413 psi | 45% | 1850 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 48,341 psi | 76% | 2999 fps | 98.6% |
| IMR 7828 SSC | <<locked>> | 80% | 43,903 psi | 69% | 2995 fps | 98.1% |
| IMR 8133 Enduron | <<locked>> | 86% | 35,172 psi | 55% | 2799 fps | 95.5% |
| Lovex S071 | <<locked>> | 80% | 39,479 psi | 62% | 2799 fps | 99.6% |
| Norma 217 | <<locked>> | 82% | 30,835 psi | 48% | 2694 fps | 95.9% |
| Norma MRP | <<locked>> | 80% | 48,994 psi | 77% | 3094 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 44,309 psi | 69% | 3009 fps | 98.5% |
| Ramshot Magnum | <<locked>> | 80% | 39,987 psi | 63% | 2874 fps | 98.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,182 psi | 46% | 1896 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 37,304 psi | 58% | 2904 fps | 99.1% |
| ReloadSwiss RS 80 | <<locked>> | 84% | 40,059 psi | 63% | 2930 fps | 96% |
| Rottweil R 904 | <<locked>> | 80% | 50,444 psi | 79% | 3045 fps | 99.2% |
| Rottweil R 905 | <<locked>> | 80% | 49,400 psi | 77% | 3054 fps | 99.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 49,066 psi | 77% | 3051 fps | 99.7% |
| Somchem S361 | <<locked>> | 80% | 51,474 psi | 81% | 3028 fps | 99% |
| Somchem S385 | <<locked>> | 80% | 49,792 psi | 78% | 3025 fps | 99.9% |
| Vihtavuori N165 | <<locked>> | 80% | 43,598 psi | 68% | 2894 fps | 99.3% |
| Vihtavuori N170 | <<locked>> | 88% | 48,994 psi | 77% | 3018 fps | 95% |
| Vihtavuori N555 | <<locked>> | 80% | 49,356 psi | 77% | 3031 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 48,515 psi | 76% | 3091 fps | 98.6% |
| Vihtavuori N565 | <<locked>> | 80% | 40,466 psi | 63% | 2894 fps | 96.9% |
| Vihtavuori N568 | <<locked>> | 84% | 41,162 psi | 65% | 2949 fps | 95.7% |
| Vihtavuori N570 | <<locked>> | 88% | 45,208 psi | 71% | 3077 fps | 95% |
| Winchester StaBALL HD | <<locked>> | 80% | 43,671 psi | 68% | 3015 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 46,021 psi | 72% | 2953 fps | 99.3% |
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 | 170gr | Speer Deep Curl Flat Points. ADI AR 2218 delivers the highest muzzle velocity at 3,310 fps; across all powders the maximum-charge window runs from 2,064 fps to 3,310 fps. Accurate 8700 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 170.0 gr projectile in 0.308" calls for a 1:14.5 twist; slower twists will usually not stabilise this weight. Accurate 8700, Alliant Reloder-50, 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. As outliers, Hodgdon US 869, Lovex D100, Ramshot LRT 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.