Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 180gr | Speer RN bullet and 51 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ADI AR 2218, Hodgdon Retumbo and ReloadSwiss RS 76.
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>> | 84% | 55,056 psi | 86% | 3018 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 50,604 psi | 79% | 3041 fps | 97.2% |
| Accurate High Country | <<locked>> | 82% | 57,029 psi | 89% | 3186 fps | 100% |
| Accurate MAGPRO | <<locked>> | 82% | 54,041 psi | 85% | 3123 fps | 99.4% |
| ADI AR 2209 | <<locked>> | 82% | 55,898 psi | 88% | 3107 fps | 100% |
| ADI AR 2213 | <<locked>> | 84% | 54,592 psi | 86% | 3120 fps | 99.9% |
| ADI AR 2217 | <<locked>> | 92% | 54,143 psi | 85% | 3107 fps | 100% |
| ADI AR 2218 | <<locked>> | 96% | 54,636 psi | 86% | 3232 fps | 98.8% |
| ADI AR 2225 | <<locked>> | 96% | 57,551 psi | 90% | 3192 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 82% | 56,072 psi | 88% | 3104 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 55,506 psi | 87% | 3094 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 84% | 55,187 psi | 86% | 3117 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 57,217 psi | 90% | 3074 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 88% | 54,244 psi | 85% | 3100 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 56,666 psi | 89% | 3209 fps | 98.8% |
| Alliant Reloder-50 | <<locked>> | 98% | 56,898 psi | 89% | 3202 fps | 98.4% |
| Baschieri & Pellagri 109 | <<locked>> | 86% | 54,969 psi | 86% | 3081 fps | 98.6% |
| Bofors RP15 | <<locked>> | 86% | 54,781 psi | 86% | 3107 fps | 100% |
| Bofors RP30 | <<locked>> | 90% | 54,215 psi | 85% | 3120 fps | 100% |
| Bofors RP5 | <<locked>> | 84% | 55,187 psi | 86% | 3117 fps | 100% |
| Hodgdon H1000 | <<locked>> | 90% | 55,390 psi | 87% | 3123 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 57,217 psi | 90% | 3114 fps | 99.8% |
| Hodgdon H4831 SC | <<locked>> | 84% | 56,057 psi | 88% | 3094 fps | 99.8% |
| Hodgdon Retumbo | <<locked>> | 88% | 53,896 psi | 84% | 3196 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,956 psi | 59% | 2018 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 57,232 psi | 90% | 3087 fps | 99.9% |
| IMR 7828 SSC | <<locked>> | 86% | 57,116 psi | 90% | 3169 fps | 100% |
| IMR 8133 Enduron | <<locked>> | 98% | 56,521 psi | 89% | 3173 fps | 100% |
| Lovex S071 | <<locked>> | 90% | 57,174 psi | 90% | 3048 fps | 100% |
| Norma 217 | <<locked>> | 96% | 54,128 psi | 85% | 3133 fps | 100% |
| Norma MRP | <<locked>> | 82% | 55,419 psi | 87% | 3133 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 54,650 psi | 86% | 3133 fps | 100% |
| Ramshot Magnum | <<locked>> | 88% | 57,145 psi | 90% | 3117 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 39,059 psi | 61% | 2064 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 54,447 psi | 85% | 3176 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 90% | 53,722 psi | 84% | 3140 fps | 99.5% |
| Rottweil R 904 | <<locked>> | 82% | 56,057 psi | 88% | 3071 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 82% | 55,419 psi | 87% | 3087 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 52,547 psi | 82% | 3054 fps | 97.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 82% | 55,056 psi | 86% | 3084 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 57,406 psi | 90% | 3061 fps | 99.8% |
| Somchem S385 | <<locked>> | 82% | 55,593 psi | 87% | 3054 fps | 100% |
| Vihtavuori N165 | <<locked>> | 86% | 55,782 psi | 87% | 3041 fps | 100% |
| Vihtavuori N170 | <<locked>> | 90% | 55,100 psi | 86% | 3071 fps | 97.2% |
| Vihtavuori N555 | <<locked>> | 82% | 55,317 psi | 87% | 3051 fps | 100% |
| Vihtavuori N560 | <<locked>> | 82% | 54,737 psi | 86% | 3136 fps | 99.7% |
| Vihtavuori N565 | <<locked>> | 88% | 56,231 psi | 88% | 3136 fps | 99.9% |
| Vihtavuori N568 | <<locked>> | 90% | 54,215 psi | 85% | 3146 fps | 99.3% |
| Vihtavuori N570 | <<locked>> | 92% | 55,608 psi | 87% | 3215 fps | 98.3% |
| Winchester StaBALL HD | <<locked>> | 84% | 54,302 psi | 85% | 3114 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 84% | 55,405 psi | 87% | 3051 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% | 48,167 psi | 75% | 2904 fps | 100% |
| Accurate 8700 | <<locked>> | 96% | 43,627 psi | 68% | 2907 fps | 95.1% |
| Accurate High Country | <<locked>> | 80% | 53,200 psi | 83% | 3117 fps | 99.8% |
| Accurate MAGPRO | <<locked>> | 80% | 50,401 psi | 79% | 3058 fps | 98.9% |
| ADI AR 2209 | <<locked>> | 80% | 52,257 psi | 82% | 3045 fps | 100% |
| ADI AR 2213 | <<locked>> | 80% | 47,558 psi | 75% | 2992 fps | 99.2% |
| ADI AR 2217 | <<locked>> | 80% | 35,534 psi | 56% | 2720 fps | 96.6% |
| ADI AR 2218 | 110.7 gr | 90% | 43,714 psi | 69% | 2999 fps | 95.7% |
| ADI AR 2225 | <<locked>> | 80% | 32,880 psi | 52% | 2690 fps | 98.5% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 52,518 psi | 82% | 3041 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 80% | 52,040 psi | 82% | 3035 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 48,312 psi | 76% | 2995 fps | 99.8% |
| Alliant Reloder-23 | <<locked>> | 80% | 47,079 psi | 74% | 2917 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 41,234 psi | 65% | 2867 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 86% | 41,974 psi | 66% | 2917 fps | 95.1% |
| Alliant Reloder-50 | <<locked>> | 92% | 45,469 psi | 71% | 2982 fps | 95.7% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 45,165 psi | 71% | 2894 fps | 96.5% |
| Bofors RP15 | <<locked>> | 80% | 45,005 psi | 71% | 2927 fps | 99.4% |
| Bofors RP30 | <<locked>> | 80% | 38,537 psi | 60% | 2802 fps | 97.6% |
| Bofors RP5 | <<locked>> | 80% | 48,312 psi | 76% | 2995 fps | 99.8% |
| Hodgdon H1000 | <<locked>> | 80% | 38,696 psi | 61% | 2802 fps | 98.2% |
| Hodgdon H4831 | <<locked>> | 80% | 49,922 psi | 78% | 2986 fps | 99.1% |
| Hodgdon H4831 SC | <<locked>> | 80% | 49,052 psi | 77% | 2972 fps | 99% |
| Hodgdon Retumbo | 92.9 gr | 80% | 40,321 psi | 63% | 2927 fps | 99.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,500 psi | 45% | 1808 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 50,415 psi | 79% | 2969 fps | 99.3% |
| IMR 7828 SSC | <<locked>> | 80% | 46,383 psi | 73% | 2976 fps | 99% |
| IMR 8133 Enduron | <<locked>> | 82% | 32,634 psi | 51% | 2664 fps | 95.1% |
| Lovex S071 | <<locked>> | 80% | 41,466 psi | 65% | 2776 fps | 99.9% |
| Norma 217 | <<locked>> | 80% | 30,835 psi | 48% | 2631 fps | 96.7% |
| Norma MRP | <<locked>> | 80% | 51,648 psi | 81% | 3068 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 47,050 psi | 74% | 2992 fps | 99.4% |
| Ramshot Magnum | <<locked>> | 80% | 42,453 psi | 67% | 2861 fps | 99.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,298 psi | 46% | 1850 fps | 100% |
| ReloadSwiss RS 76 | 99.4 gr | 80% | 39,914 psi | 63% | 2900 fps | 99.9% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 36,767 psi | 58% | 2779 fps | 95.4% |
| Rottweil R 904 | <<locked>> | 80% | 52,649 psi | 83% | 3015 fps | 99.7% |
| Rottweil R 905 | <<locked>> | 80% | 51,837 psi | 81% | 3028 fps | 100% |
| SNPE Vectan SP 13 | <<locked>> | 96% | 45,629 psi | 72% | 2920 fps | 95.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 51,488 psi | 81% | 3022 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 53,795 psi | 84% | 3002 fps | 99.6% |
| Somchem S385 | <<locked>> | 80% | 52,127 psi | 82% | 2995 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 45,774 psi | 72% | 2871 fps | 99.8% |
| Vihtavuori N170 | <<locked>> | 86% | 48,153 psi | 75% | 2940 fps | 95.5% |
| Vihtavuori N555 | <<locked>> | 80% | 51,924 psi | 81% | 2999 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 51,053 psi | 80% | 3071 fps | 99.4% |
| Vihtavuori N565 | <<locked>> | 80% | 42,801 psi | 67% | 2881 fps | 98.1% |
| Vihtavuori N568 | <<locked>> | 80% | 37,811 psi | 59% | 2802 fps | 95.2% |
| Vihtavuori N570 | <<locked>> | 86% | 44,831 psi | 70% | 2999 fps | 95.6% |
| Winchester StaBALL HD | <<locked>> | 80% | 46,818 psi | 73% | 2992 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 48,283 psi | 76% | 2927 fps | 99.8% |
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 | 180gr | Speer RN. ADI AR 2218 delivers the highest muzzle velocity at 3,232 fps; across all powders the maximum-charge window runs from 2,018 fps to 3,232 fps. Accurate 8700 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 180.0 gr projectile in 0.308" calls for a 1:16.0 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, Hodgdon Retumbo, ReloadSwiss RS 76 rank at the top here: for .30-378 Weath. Mag. with the .308 | 180gr | Speer RN 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.