Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 188gr | Discreet Ballistics Selous Machined Expander 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, Vihtavuori N570 and Hodgdon Retumbo.
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% | 54,563 psi | 86% | 2956 fps | 100% |
| Accurate 8700ᴾ | <<locked>> | 100% | 49,748 psi | 78% | 2982 fps | 97.3% |
| Accurate MAGPRO | <<locked>> | 84% | 57,508 psi | 90% | 3130 fps | 99.8% |
| ADI AR 2209 | <<locked>> | 82% | 55,434 psi | 87% | 3041 fps | 100% |
| ADI AR 2213 | <<locked>> | 84% | 54,143 psi | 85% | 3058 fps | 99.9% |
| ADI AR 2217 | <<locked>> | 94% | 57,406 psi | 90% | 3104 fps | 100% |
| ADI AR 2218 | <<locked>> | 96% | 53,838 psi | 84% | 3169 fps | 98.8% |
| ADI AR 2225 | <<locked>> | 96% | 56,826 psi | 89% | 3127 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 55,114 psi | 86% | 3031 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 84% | 54,737 psi | 86% | 3054 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 86% | 56,898 psi | 89% | 3012 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 57,493 psi | 90% | 3094 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 57,624 psi | 90% | 3104 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 94% | 55,912 psi | 88% | 3146 fps | 98.8% |
| Alliant Reloder-50 | <<locked>> | 98% | 56,043 psi | 88% | 3140 fps | 98.5% |
| Baschieri & Pellagri 109 | <<locked>> | 86% | 54,476 psi | 85% | 3018 fps | 98.7% |
| Bofors RP15 | <<locked>> | 86% | 54,302 psi | 85% | 3045 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 57,363 psi | 90% | 3117 fps | 100% |
| Bofors RP5 | <<locked>> | 84% | 54,737 psi | 86% | 3054 fps | 100% |
| Hodgdon H1000 | <<locked>> | 90% | 54,926 psi | 86% | 3064 fps | 100% |
| Hodgdon H4831 | <<locked>> | 84% | 56,637 psi | 89% | 3048 fps | 99.9% |
| Hodgdon H4831 SC | <<locked>> | 84% | 55,637 psi | 87% | 3031 fps | 99.8% |
| Hodgdon Retumbo | <<locked>> | 90% | 57,101 psi | 89% | 3189 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 38,014 psi | 60% | 1965 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 56,782 psi | 89% | 3022 fps | 99.9% |
| IMR 7828 SSC | <<locked>> | 86% | 56,710 psi | 89% | 3107 fps | 100% |
| IMR 7977 Enduron | <<locked>> | 90% | 55,448 psi | 87% | 2972 fps | 96% |
| IMR 8133 Enduron | <<locked>> | 98% | 55,825 psi | 87% | 3110 fps | 100% |
| Lovex S071 | <<locked>> | 90% | 56,565 psi | 89% | 2982 fps | 100% |
| Norma 217 | <<locked>> | 98% | 57,276 psi | 90% | 3130 fps | 100% |
| Norma MRP | <<locked>> | 82% | 54,955 psi | 86% | 3071 fps | 100% |
| Ramshot Grand | <<locked>> | 84% | 54,099 psi | 85% | 3068 fps | 100% |
| Ramshot Magnum | <<locked>> | 88% | 56,623 psi | 89% | 3054 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 39,001 psi | 61% | 2011 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 88% | 53,766 psi | 84% | 3110 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 57,217 psi | 90% | 3146 fps | 99.9% |
| Rottweil R 904 | <<locked>> | 82% | 55,738 psi | 87% | 3009 fps | 100% |
| Rottweil R 905 | <<locked>> | 82% | 54,955 psi | 86% | 3025 fps | 100% |
| SNPE Vectan SP 13ᴾ | <<locked>> | 100% | 51,779 psi | 81% | 2992 fps | 97.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 82% | 54,592 psi | 86% | 3018 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 57,000 psi | 89% | 2999 fps | 99.9% |
| Somchem S385 | <<locked>> | 82% | 55,230 psi | 87% | 2989 fps | 100% |
| Vihtavuori N165 | <<locked>> | 86% | 55,245 psi | 87% | 2979 fps | 100% |
| Vihtavuori N170 | <<locked>> | 90% | 54,549 psi | 85% | 3009 fps | 97.3% |
| Vihtavuori N555 | <<locked>> | 82% | 54,882 psi | 86% | 2989 fps | 100% |
| Vihtavuori N560 | <<locked>> | 82% | 54,331 psi | 85% | 3074 fps | 99.8% |
| Vihtavuori N565 | <<locked>> | 88% | 55,579 psi | 87% | 3071 fps | 99.9% |
| Vihtavuori N568 | <<locked>> | 92% | 57,493 psi | 90% | 3150 fps | 99.7% |
| Vihtavuori N570 | <<locked>> | 92% | 55,071 psi | 86% | 3153 fps | 98.4% |
| Winchester StaBALL HD | <<locked>> | 84% | 53,853 psi | 84% | 3051 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 84% | 54,897 psi | 86% | 2986 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% | 47,805 psi | 75% | 2844 fps | 100% |
| Accurate 8700 | <<locked>> | 96% | 42,960 psi | 67% | 2844 fps | 95.2% |
| Accurate MAGPRO | <<locked>> | 80% | 49,980 psi | 78% | 2999 fps | 99% |
| ADI AR 2209 | <<locked>> | 80% | 51,895 psi | 81% | 2982 fps | 100% |
| ADI AR 2213 | <<locked>> | 80% | 47,079 psi | 74% | 2930 fps | 99.3% |
| ADI AR 2217 | <<locked>> | 80% | 35,215 psi | 55% | 2667 fps | 96.9% |
| ADI AR 2218 | 106.6 gr | 90% | 43,149 psi | 68% | 2940 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 80% | 32,503 psi | 51% | 2635 fps | 98.6% |
| Alliant Reloder-19 | <<locked>> | 80% | 51,677 psi | 81% | 2972 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 80% | 47,863 psi | 75% | 2933 fps | 99.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 46,601 psi | 73% | 2854 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 40,843 psi | 64% | 2808 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 80% | 53,505 psi | 84% | 3041 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 86% | 41,365 psi | 65% | 2858 fps | 95.3% |
| Alliant Reloder-50 | <<locked>> | 92% | 44,715 psi | 70% | 2923 fps | 95.8% |
| Baschieri & Pellagri 109 | <<locked>> | 80% | 44,802 psi | 70% | 2835 fps | 96.7% |
| Bofors RP15 | <<locked>> | 80% | 44,614 psi | 70% | 2867 fps | 99.5% |
| Bofors RP30 | <<locked>> | 80% | 38,189 psi | 60% | 2746 fps | 97.8% |
| Bofors RP5 | <<locked>> | 80% | 47,863 psi | 75% | 2933 fps | 99.9% |
| Hodgdon H1000 | <<locked>> | 80% | 38,290 psi | 60% | 2743 fps | 98.4% |
| Hodgdon H4831 | <<locked>> | 80% | 49,501 psi | 78% | 2923 fps | 99.2% |
| Hodgdon H4831 SC | <<locked>> | 80% | 48,602 psi | 76% | 2910 fps | 99.1% |
| Hodgdon Retumbo | 89.4 gr | 80% | 39,842 psi | 62% | 2867 fps | 99.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,558 psi | 45% | 1759 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 50,053 psi | 78% | 2907 fps | 99.4% |
| IMR 7828 SSC | <<locked>> | 80% | 45,890 psi | 72% | 2917 fps | 99.2% |
| IMR 7977 Enduron | <<locked>> | 88% | 52,011 psi | 82% | 2913 fps | 95.1% |
| IMR 8133 Enduron | <<locked>> | 82% | 32,314 psi | 51% | 2615 fps | 95.4% |
| Lovex S071 | <<locked>> | 80% | 41,176 psi | 65% | 2717 fps | 100% |
| Norma 217 | <<locked>> | 80% | 30,472 psi | 48% | 2579 fps | 96.9% |
| Norma MRP | <<locked>> | 80% | 51,140 psi | 80% | 3005 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 46,630 psi | 73% | 2936 fps | 99.5% |
| Ramshot Magnum | <<locked>> | 80% | 42,003 psi | 66% | 2802 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,385 psi | 46% | 1801 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 80% | 39,407 psi | 62% | 2841 fps | 99.9% |
| ReloadSwiss RS 80 | <<locked>> | 80% | 36,318 psi | 57% | 2726 fps | 95.6% |
| Rottweil R 904 | <<locked>> | 80% | 52,257 psi | 82% | 2949 fps | 99.8% |
| Rottweil R 905 | <<locked>> | 80% | 51,430 psi | 81% | 2966 fps | 100% |
| SNPE Vectan SP 13 | <<locked>> | 96% | 45,165 psi | 71% | 2867 fps | 95.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 51,082 psi | 80% | 2959 fps | 100% |
| Somchem S361 | <<locked>> | 80% | 53,461 psi | 84% | 2940 fps | 99.6% |
| Somchem S385 | <<locked>> | 80% | 51,677 psi | 81% | 2933 fps | 100% |
| Vihtavuori N165 | <<locked>> | 80% | 45,440 psi | 71% | 2812 fps | 99.8% |
| Vihtavuori N170 | <<locked>> | 86% | 47,747 psi | 75% | 2881 fps | 95.7% |
| Vihtavuori N555 | <<locked>> | 80% | 51,416 psi | 81% | 2933 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 50,560 psi | 79% | 3009 fps | 99.5% |
| Vihtavuori N565 | <<locked>> | 80% | 42,409 psi | 66% | 2822 fps | 98.3% |
| Vihtavuori N568 | <<locked>> | 80% | 37,405 psi | 59% | 2746 fps | 95.4% |
| Vihtavuori N570 | 99.8 gr | 86% | 44,295 psi | 69% | 2943 fps | 95.8% |
| Winchester StaBALL HD | <<locked>> | 80% | 46,296 psi | 73% | 2933 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 47,906 psi | 75% | 2867 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 57 powders for .30-378 Weath. Mag. loaded with the .308 | 188gr | Discreet Ballistics Selous Machined Expander. Hodgdon Retumbo delivers the highest muzzle velocity at 3,189 fps; across all powders the maximum-charge window runs from 1,965 fps to 3,189 fps. Accurate 8700 gives the best case fill at 100 %, and 57 of the 57 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 60–90 %, leaving at least 10 % headroom. The 188.0 gr projectile in 0.308" calls for a 1:12.0 twist; slower twists will usually not stabilise this weight. Accurate 8700, Hodgdon TrailBoss, Hodgdon US 869 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, Hodgdon Retumbo rank at the top here: for .30-378 Weath. Mag. with the .308 | 188gr | Discreet Ballistics Selous Machined Expander they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Hodgdon US 869, Vihtavuori 20N29, Vihtavuori 24N41 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.