Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 170gr | Swift A-Frame bullet and 50 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ADI AR 2218, Vihtavuori N570 and Alliant Reloder-33.
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% | 57,261 psi | 90% | 3123 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 48,733 psi | 76% | 3071 fps | 96.1% |
| Accurate MAGPRO | <<locked>> | 84% | 56,289 psi | 88% | 3235 fps | 99.4% |
| ADI AR 2209 | <<locked>> | 82% | 54,389 psi | 85% | 3156 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 56,985 psi | 89% | 3235 fps | 99.9% |
| ADI AR 2217 | <<locked>> | 94% | 56,130 psi | 88% | 3212 fps | 100% |
| ADI AR 2218 | <<locked>> | 98% | 56,971 psi | 89% | 3343 fps | 98.7% |
| ADI AR 2225 | <<locked>> | 96% | 55,666 psi | 87% | 3235 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 57,609 psi | 90% | 3202 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 86% | 57,479 psi | 90% | 3228 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 55,680 psi | 87% | 3130 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 56,362 psi | 88% | 3209 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 56,391 psi | 88% | 3219 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 54,694 psi | 86% | 3241 fps | 98% |
| Alliant Reloder-50 | <<locked>> | 98% | 54,781 psi | 86% | 3232 fps | 97.6% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 57,188 psi | 90% | 3189 fps | 98.6% |
| Bofors RP15 | <<locked>> | 88% | 56,826 psi | 89% | 3219 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 56,231 psi | 88% | 3228 fps | 99.9% |
| Bofors RP5 | <<locked>> | 86% | 57,479 psi | 90% | 3228 fps | 100% |
| Hodgdon H1000 | <<locked>> | 92% | 57,624 psi | 90% | 3235 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 55,724 psi | 87% | 3163 fps | 99.5% |
| Hodgdon H4831 SC | <<locked>> | 84% | 54,636 psi | 86% | 3143 fps | 99.4% |
| Hodgdon Retumbo | <<locked>> | 90% | 55,695 psi | 87% | 3304 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,913 psi | 59% | 2073 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 55,840 psi | 88% | 3136 fps | 99.6% |
| IMR 7828 SSC | <<locked>> | 86% | 55,419 psi | 87% | 3215 fps | 99.8% |
| IMR 8133 Enduron | <<locked>> | 98% | 54,636 psi | 86% | 3212 fps | 99.9% |
| Lovex S071 | <<locked>> | 90% | 55,492 psi | 87% | 3097 fps | 100% |
| Norma 217 | <<locked>> | 98% | 56,144 psi | 88% | 3238 fps | 100% |
| Norma MRP | <<locked>> | 84% | 57,653 psi | 90% | 3245 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 56,898 psi | 89% | 3241 fps | 100% |
| Ramshot Magnum | <<locked>> | 88% | 55,361 psi | 87% | 3159 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,841 psi | 61% | 2119 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 56,840 psi | 89% | 3287 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 55,970 psi | 88% | 3251 fps | 99.5% |
| Rottweil R 904 | <<locked>> | 82% | 54,810 psi | 86% | 3123 fps | 99.7% |
| Rottweil R 905 | <<locked>> | 84% | 57,566 psi | 90% | 3199 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 50,821 psi | 80% | 3087 fps | 96.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 57,188 psi | 90% | 3192 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 56,202 psi | 88% | 3110 fps | 99.6% |
| Somchem S385 | <<locked>> | 82% | 54,259 psi | 85% | 3104 fps | 100% |
| Vihtavuori N165 | <<locked>> | 86% | 54,331 psi | 85% | 3091 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 57,479 psi | 90% | 3176 fps | 97.2% |
| Vihtavuori N555 | <<locked>> | 84% | 57,348 psi | 90% | 3159 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 56,927 psi | 89% | 3248 fps | 99.7% |
| Vihtavuori N565 | <<locked>> | 88% | 54,491 psi | 85% | 3179 fps | 99.6% |
| Vihtavuori N568 | <<locked>> | 92% | 56,449 psi | 88% | 3255 fps | 99.3% |
| Vihtavuori N570 | <<locked>> | 92% | 53,838 psi | 84% | 3251 fps | 97.5% |
| Winchester StaBALL HD | <<locked>> | 86% | 56,536 psi | 89% | 3225 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 84% | 53,940 psi | 85% | 3097 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% | 46,818 psi | 73% | 2949 fps | 100% |
| Accurate 8700 | <<locked>> | 98% | 45,266 psi | 71% | 3002 fps | 95% |
| Accurate MAGPRO | <<locked>> | 80% | 48,936 psi | 77% | 3097 fps | 98.3% |
| ADI AR 2209 | <<locked>> | 80% | 50,865 psi | 80% | 3094 fps | 99.8% |
| ADI AR 2213 | <<locked>> | 80% | 46,137 psi | 72% | 3035 fps | 98.6% |
| ADI AR 2217 | <<locked>> | 80% | 34,418 psi | 54% | 2749 fps | 95.4% |
| ADI AR 2218 | 114.5 gr | 92% | 45,484 psi | 71% | 3100 fps | 95.6% |
| ADI AR 2225 | <<locked>> | 80% | 31,763 psi | 50% | 2717 fps | 97.4% |
| Alliant Reloder-19 | <<locked>> | 80% | 50,676 psi | 79% | 3081 fps | 99.8% |
| Alliant Reloder-22 | <<locked>> | 80% | 46,905 psi | 74% | 3035 fps | 99.5% |
| Alliant Reloder-23 | <<locked>> | 80% | 45,542 psi | 71% | 2963 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 39,827 psi | 62% | 2904 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 80% | 52,402 psi | 82% | 3153 fps | 100% |
| Alliant Reloder-33 | 111.5 gr | 88% | 43,598 psi | 68% | 3015 fps | 95% |
| Alliant Reloder-50 | <<locked>> | 94% | 47,181 psi | 74% | 3084 fps | 95.6% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 44,077 psi | 69% | 2933 fps | 95.6% |
| Bofors RP15 | <<locked>> | 80% | 43,685 psi | 68% | 2966 fps | 98.9% |
| Bofors RP30 | <<locked>> | 80% | 37,217 psi | 58% | 2835 fps | 96.6% |
| Bofors RP5 | <<locked>> | 80% | 46,905 psi | 74% | 3035 fps | 99.5% |
| Hodgdon H1000 | <<locked>> | 80% | 37,463 psi | 59% | 2835 fps | 97.3% |
| Hodgdon H4831 | <<locked>> | 80% | 48,530 psi | 76% | 3028 fps | 98.6% |
| Hodgdon H4831 SC | <<locked>> | 80% | 47,688 psi | 75% | 3012 fps | 98.4% |
| Hodgdon Retumbo | <<locked>> | 80% | 38,914 psi | 61% | 2956 fps | 98.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,456 psi | 45% | 1857 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 49,211 psi | 77% | 3015 fps | 98.8% |
| IMR 7828 SSC | <<locked>> | 80% | 44,918 psi | 70% | 3015 fps | 98.4% |
| IMR 8133 Enduron | <<locked>> | 86% | 36,172 psi | 57% | 2822 fps | 96% |
| Lovex S071 | <<locked>> | 80% | 40,321 psi | 63% | 2818 fps | 99.7% |
| Norma 217 | <<locked>> | 80% | 29,515 psi | 46% | 2648 fps | 95.2% |
| Norma MRP | <<locked>> | 80% | 50,024 psi | 78% | 3114 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 45,397 psi | 71% | 3031 fps | 98.8% |
| Ramshot Magnum | <<locked>> | 80% | 41,031 psi | 64% | 2897 fps | 99.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,225 psi | 46% | 1903 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 38,464 psi | 60% | 2930 fps | 99.4% |
| ReloadSwiss RS 80 | <<locked>> | 82% | 38,159 psi | 60% | 2877 fps | 95.3% |
| Rottweil R 904 | <<locked>> | 80% | 51,372 psi | 81% | 3061 fps | 99.4% |
| Rottweil R 905 | <<locked>> | 80% | 50,430 psi | 79% | 3074 fps | 99.8% |
| SNPE Vectan SP 13 | <<locked>> | 98% | 47,384 psi | 74% | 3018 fps | 95.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 50,082 psi | 78% | 3068 fps | 99.8% |
| Somchem S361 | <<locked>> | 80% | 52,547 psi | 82% | 3048 fps | 99.2% |
| Somchem S385 | <<locked>> | 80% | 50,749 psi | 80% | 3045 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 44,498 psi | 70% | 2913 fps | 99.4% |
| Vihtavuori N170 | <<locked>> | 88% | 50,125 psi | 79% | 3041 fps | 95.4% |
| Vihtavuori N555 | <<locked>> | 80% | 50,328 psi | 79% | 3045 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 49,501 psi | 78% | 3110 fps | 98.8% |
| Vihtavuori N565 | <<locked>> | 80% | 41,394 psi | 65% | 2913 fps | 97.2% |
| Vihtavuori N568 | <<locked>> | 82% | 39,262 psi | 62% | 2900 fps | 95.1% |
| Vihtavuori N570 | 107.3 gr | 88% | 46,514 psi | 73% | 3104 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 80% | 44,918 psi | 70% | 3035 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 46,934 psi | 74% | 2972 fps | 99.5% |
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 50 powders for .30-378 Weath. Mag. loaded with the .308 | 170gr | Swift A-Frame. ADI AR 2218 delivers the highest muzzle velocity at 3,343 fps; across all powders the maximum-charge window runs from 2,073 fps to 3,343 fps. Accurate 8700 gives the best case fill at 100 %, and 50 of the 50 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 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 8700, Hodgdon TrailBoss, ReloadSwiss RS 14 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. ADI AR 2218, Vihtavuori N570, Alliant Reloder-33 rank at the top here: for .30-378 Weath. Mag. with the .308 | 170gr | Swift A-Frame 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.