Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 170gr | Lapua Lock Base bullet and 51 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon Retumbo, ReloadSwiss RS 76 and ADI AR 2218.
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% | 55,796 psi | 87% | 3104 fps | 100% |
| Accurate High Country | <<locked>> | 84% | 57,580 psi | 90% | 3268 fps | 99.9% |
| Accurate MAGPRO | <<locked>> | 84% | 54,723 psi | 86% | 3209 fps | 99.1% |
| ADI AR 2209 | <<locked>> | 84% | 56,768 psi | 89% | 3196 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 55,347 psi | 87% | 3209 fps | 99.7% |
| ADI AR 2217 | <<locked>> | 94% | 54,418 psi | 85% | 3186 fps | 99.9% |
| ADI AR 2218 | <<locked>> | 98% | 54,911 psi | 86% | 3304 fps | 98.2% |
| ADI AR 2225 | <<locked>> | 98% | 57,740 psi | 90% | 3271 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 56,942 psi | 89% | 3192 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 56,347 psi | 88% | 3182 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 86% | 55,869 psi | 88% | 3205 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 54,099 psi | 85% | 3110 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 54,679 psi | 86% | 3186 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 54,650 psi | 86% | 3192 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 96% | 56,869 psi | 89% | 3284 fps | 98.3% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 56,869 psi | 89% | 3271 fps | 97.9% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 55,840 psi | 88% | 3166 fps | 98.3% |
| Bofors RP15 | <<locked>> | 88% | 55,405 psi | 87% | 3196 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 54,491 psi | 85% | 3202 fps | 99.9% |
| Bofors RP5 | <<locked>> | 86% | 55,869 psi | 88% | 3205 fps | 100% |
| Hodgdon H1000 | <<locked>> | 92% | 55,825 psi | 87% | 3209 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 54,360 psi | 85% | 3140 fps | 99.3% |
| Hodgdon H4831 SC | <<locked>> | 86% | 56,971 psi | 89% | 3182 fps | 99.6% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 57,043 psi | 89% | 3094 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 90% | 53,867 psi | 84% | 3274 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,768 psi | 59% | 2064 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 54,679 psi | 86% | 3117 fps | 99.4% |
| IMR 7828 SSC | <<locked>> | 86% | 53,911 psi | 84% | 3192 fps | 99.6% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 56,623 psi | 89% | 3251 fps | 99.9% |
| Lovex S071 | <<locked>> | 92% | 57,624 psi | 90% | 3130 fps | 100% |
| Norma 217 | <<locked>> | 98% | 53,969 psi | 85% | 3212 fps | 100% |
| Norma MRP | <<locked>> | 84% | 55,956 psi | 88% | 3219 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 55,129 psi | 86% | 3215 fps | 99.9% |
| Ramshot Magnum | <<locked>> | 88% | 53,650 psi | 84% | 3136 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,841 psi | 61% | 2113 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 54,578 psi | 86% | 3258 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 54,012 psi | 85% | 3219 fps | 99.2% |
| Rottweil R 904 | <<locked>> | 84% | 57,058 psi | 89% | 3159 fps | 99.8% |
| Rottweil R 905 | <<locked>> | 84% | 56,217 psi | 88% | 3176 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 55,840 psi | 88% | 3169 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 54,853 psi | 86% | 3091 fps | 99.4% |
| Somchem S385 | <<locked>> | 84% | 56,434 psi | 88% | 3140 fps | 100% |
| Vihtavuori N165 | <<locked>> | 88% | 56,420 psi | 88% | 3127 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 55,912 psi | 88% | 3150 fps | 96.7% |
| Vihtavuori N555 | <<locked>> | 84% | 55,883 psi | 88% | 3136 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 55,347 psi | 87% | 3222 fps | 99.5% |
| Vihtavuori N565 | <<locked>> | 90% | 56,608 psi | 89% | 3219 fps | 99.7% |
| Vihtavuori N568 | <<locked>> | 92% | 54,433 psi | 85% | 3222 fps | 99% |
| Vihtavuori N570 | <<locked>> | 94% | 55,767 psi | 87% | 3287 fps | 97.8% |
| Winchester StaBALL HD | <<locked>> | 86% | 54,563 psi | 86% | 3202 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 56,289 psi | 88% | 3136 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% | 45,498 psi | 71% | 2927 fps | 100% |
| Accurate High Country | <<locked>> | 80% | 50,154 psi | 79% | 3133 fps | 99.2% |
| Accurate MAGPRO | <<locked>> | 80% | 47,514 psi | 74% | 3071 fps | 97.9% |
| ADI AR 2209 | <<locked>> | 80% | 49,516 psi | 78% | 3068 fps | 99.6% |
| ADI AR 2213 | <<locked>> | 80% | 44,817 psi | 70% | 3009 fps | 98.3% |
| ADI AR 2217 | <<locked>> | 82% | 35,810 psi | 56% | 2789 fps | 95.9% |
| ADI AR 2218 | 114.2 gr | 94% | 47,384 psi | 74% | 3146 fps | 96.2% |
| ADI AR 2225 | <<locked>> | 80% | 30,777 psi | 48% | 2687 fps | 96.8% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 49,864 psi | 78% | 3068 fps | 99.7% |
| Alliant Reloder-19 | <<locked>> | 80% | 49,400 psi | 77% | 3058 fps | 99.6% |
| Alliant Reloder-22 | <<locked>> | 80% | 45,585 psi | 71% | 3012 fps | 99.2% |
| Alliant Reloder-23 | <<locked>> | 80% | 44,295 psi | 69% | 2940 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 38,522 psi | 60% | 2881 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 80% | 50,763 psi | 80% | 3130 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 90% | 45,368 psi | 71% | 3058 fps | 95.5% |
| Alliant Reloder-50 | <<locked>> | 96% | 48,907 psi | 77% | 3120 fps | 96% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 43,004 psi | 67% | 2910 fps | 95.1% |
| Bofors RP15 | <<locked>> | 80% | 42,395 psi | 66% | 2940 fps | 98.6% |
| Bofors RP30 | <<locked>> | 80% | 35,998 psi | 56% | 2805 fps | 96% |
| Bofors RP5 | <<locked>> | 80% | 45,585 psi | 71% | 3012 fps | 99.2% |
| Hodgdon H1000 | <<locked>> | 80% | 36,361 psi | 57% | 2805 fps | 96.8% |
| Hodgdon H4831 | <<locked>> | 80% | 47,326 psi | 74% | 3005 fps | 98.2% |
| Hodgdon H4831 SC | <<locked>> | 80% | 46,499 psi | 73% | 2989 fps | 98.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 53,301 psi | 84% | 3041 fps | 100% |
| Hodgdon Retumbo | 91.7 gr | 80% | 37,637 psi | 59% | 2927 fps | 98.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,340 psi | 44% | 1850 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 48,051 psi | 75% | 2992 fps | 98.5% |
| IMR 7828 SSC | <<locked>> | 80% | 43,584 psi | 68% | 2986 fps | 98% |
| IMR 8133 Enduron | <<locked>> | 86% | 34,896 psi | 55% | 2792 fps | 95.4% |
| Lovex S071 | <<locked>> | 80% | 39,276 psi | 62% | 2795 fps | 99.5% |
| Norma 217 | <<locked>> | 82% | 30,676 psi | 48% | 2690 fps | 95.8% |
| Norma MRP | <<locked>> | 80% | 48,660 psi | 76% | 3087 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 43,961 psi | 69% | 3005 fps | 98.5% |
| Ramshot Magnum | <<locked>> | 80% | 39,711 psi | 62% | 2867 fps | 98.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,124 psi | 46% | 1893 fps | 100% |
| ReloadSwiss RS 76 | 98.2 gr | 80% | 37,144 psi | 58% | 2900 fps | 99.1% |
| ReloadSwiss RS 80 | <<locked>> | 84% | 39,784 psi | 62% | 2923 fps | 95.8% |
| Rottweil R 904 | <<locked>> | 80% | 50,125 psi | 79% | 3038 fps | 99.2% |
| Rottweil R 905 | <<locked>> | 80% | 49,095 psi | 77% | 3048 fps | 99.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 48,747 psi | 76% | 3045 fps | 99.6% |
| Somchem S361 | <<locked>> | 80% | 51,343 psi | 80% | 3025 fps | 98.9% |
| Somchem S385 | <<locked>> | 80% | 49,458 psi | 78% | 3018 fps | 99.9% |
| Vihtavuori N165 | <<locked>> | 80% | 43,308 psi | 68% | 2887 fps | 99.2% |
| Vihtavuori N170 | <<locked>> | 90% | 52,199 psi | 82% | 3081 fps | 95.8% |
| Vihtavuori N555 | <<locked>> | 80% | 49,023 psi | 77% | 3025 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 48,196 psi | 76% | 3087 fps | 98.5% |
| Vihtavuori N565 | <<locked>> | 80% | 40,190 psi | 63% | 2887 fps | 96.7% |
| Vihtavuori N568 | <<locked>> | 84% | 40,872 psi | 64% | 2943 fps | 95.6% |
| Vihtavuori N570 | <<locked>> | 90% | 48,312 psi | 76% | 3146 fps | 96% |
| Winchester StaBALL HD | <<locked>> | 80% | 43,294 psi | 68% | 3009 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 45,745 psi | 72% | 2946 fps | 99.2% |
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 51 powders for .30-378 Weath. Mag. loaded with the .308 | 170gr | Lapua Lock Base. ADI AR 2218 delivers the highest muzzle velocity at 3,304 fps; across all powders the maximum-charge window runs from 2,064 fps to 3,304 fps. Alliant Reloder-50 gives the best case fill at 100 %, and 51 of the 51 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 1:13.5 twist; slower twists will usually not stabilise this weight. Alliant Reloder-50, Hodgdon TrailBoss, IMR 8133 Enduron 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. Hodgdon Retumbo, ReloadSwiss RS 76, ADI AR 2218 rank at the top here: for .30-378 Weath. Mag. with the .308 | 170gr | Lapua Lock Base 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.