Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 165gr | Alaska Bullet Works Kodiak SP PSPBC L1.136 bullet and 51 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Vihtavuori N570, 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>> | 86% | 55,071 psi | 86% | 3130 fps | 100% |
| Accurate High Country | <<locked>> | 84% | 56,956 psi | 89% | 3297 fps | 99.8% |
| Accurate MAGPRO | <<locked>> | 84% | 53,882 psi | 84% | 3232 fps | 98.9% |
| ADI AR 2209 | <<locked>> | 84% | 55,927 psi | 88% | 3219 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 54,549 psi | 85% | 3232 fps | 99.6% |
| ADI AR 2217 | <<locked>> | 96% | 57,479 psi | 90% | 3274 fps | 99.9% |
| ADI AR 2218 | <<locked>> | 98% | 54,143 psi | 85% | 3323 fps | 97.8% |
| ADI AR 2225 | <<locked>> | 98% | 56,550 psi | 89% | 3294 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 56,289 psi | 88% | 3219 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 55,695 psi | 87% | 3212 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 86% | 55,100 psi | 86% | 3228 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 88% | 57,116 psi | 90% | 3192 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 92% | 57,653 psi | 90% | 3268 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 53,751 psi | 84% | 3219 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 96% | 56,057 psi | 88% | 3304 fps | 98% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 55,898 psi | 88% | 3287 fps | 97.5% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 55,129 psi | 86% | 3186 fps | 97.9% |
| Bofors RP15 | <<locked>> | 88% | 54,636 psi | 86% | 3219 fps | 99.9% |
| Bofors RP30 | <<locked>> | 94% | 57,377 psi | 90% | 3287 fps | 99.9% |
| Bofors RP5 | <<locked>> | 86% | 55,100 psi | 86% | 3228 fps | 100% |
| Hodgdon H1000 | <<locked>> | 92% | 55,027 psi | 86% | 3232 fps | 100% |
| Hodgdon H4831 | <<locked>> | 86% | 57,421 psi | 90% | 3225 fps | 99.5% |
| Hodgdon H4831 SC | <<locked>> | 86% | 56,246 psi | 88% | 3205 fps | 99.4% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 56,275 psi | 88% | 3123 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 92% | 56,826 psi | 89% | 3366 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,768 psi | 59% | 2093 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 86% | 57,508 psi | 90% | 3199 fps | 99.6% |
| IMR 7828 SSC | <<locked>> | 88% | 56,971 psi | 89% | 3281 fps | 99.8% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 55,550 psi | 87% | 3271 fps | 99.8% |
| Lovex S071 | <<locked>> | 92% | 56,855 psi | 89% | 3156 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 56,985 psi | 89% | 3297 fps | 100% |
| Norma MRP | <<locked>> | 84% | 55,303 psi | 87% | 3245 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 54,259 psi | 85% | 3238 fps | 99.7% |
| Ramshot Magnum | <<locked>> | 90% | 56,956 psi | 89% | 3225 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,682 psi | 61% | 2139 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 53,635 psi | 84% | 3281 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 94% | 57,305 psi | 90% | 3310 fps | 99.5% |
| Rottweil R 904 | <<locked>> | 84% | 56,434 psi | 88% | 3189 fps | 99.7% |
| Rottweil R 905 | <<locked>> | 84% | 55,390 psi | 87% | 3199 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 54,998 psi | 86% | 3196 fps | 99.9% |
| Somchem S361 | <<locked>> | 82% | 54,215 psi | 85% | 3114 fps | 99.2% |
| Somchem S385 | <<locked>> | 84% | 55,738 psi | 87% | 3166 fps | 100% |
| Vihtavuori N165 | <<locked>> | 88% | 55,883 psi | 88% | 3153 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 55,085 psi | 86% | 3169 fps | 96.2% |
| Vihtavuori N555 | <<locked>> | 84% | 55,158 psi | 86% | 3166 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 54,708 psi | 86% | 3248 fps | 99.3% |
| Vihtavuori N565 | <<locked>> | 90% | 55,883 psi | 88% | 3238 fps | 99.6% |
| Vihtavuori N568 | <<locked>> | 94% | 57,595 psi | 90% | 3314 fps | 99.2% |
| Vihtavuori N570 | <<locked>> | 94% | 54,868 psi | 86% | 3307 fps | 97.3% |
| Winchester StaBALL HD | <<locked>> | 88% | 57,580 psi | 90% | 3287 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 55,593 psi | 87% | 3163 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% | 44,918 psi | 70% | 2949 fps | 99.9% |
| Accurate High Country | <<locked>> | 80% | 49,443 psi | 77% | 3156 fps | 99% |
| Accurate MAGPRO | <<locked>> | 80% | 46,833 psi | 73% | 3091 fps | 97.5% |
| ADI AR 2209 | <<locked>> | 80% | 48,950 psi | 77% | 3094 fps | 99.4% |
| ADI AR 2213 | <<locked>> | 80% | 44,208 psi | 69% | 3028 fps | 97.9% |
| ADI AR 2217 | <<locked>> | 82% | 35,230 psi | 55% | 2805 fps | 95.3% |
| ADI AR 2218 | <<locked>> | 94% | 46,630 psi | 73% | 3159 fps | 95.5% |
| ADI AR 2225 | <<locked>> | 80% | 30,313 psi | 48% | 2700 fps | 96.2% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 49,269 psi | 77% | 3094 fps | 99.5% |
| Alliant Reloder-19 | <<locked>> | 80% | 48,834 psi | 77% | 3084 fps | 99.5% |
| Alliant Reloder-22 | <<locked>> | 80% | 44,976 psi | 70% | 3035 fps | 99% |
| Alliant Reloder-23 | <<locked>> | 80% | 43,700 psi | 68% | 2969 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 37,927 psi | 59% | 2900 fps | 99.7% |
| Alliant Reloder-26 | <<locked>> | 80% | 49,951 psi | 78% | 3153 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 92% | 48,095 psi | 75% | 3150 fps | 96.1% |
| Alliant Reloder-50 | <<locked>> | 96% | 47,993 psi | 75% | 3136 fps | 95.4% |
| Baschieri & Pellagri 109 | <<locked>> | 82% | 45,339 psi | 71% | 2995 fps | 95.5% |
| Bofors RP15 | <<locked>> | 80% | 41,858 psi | 66% | 2963 fps | 98.2% |
| Bofors RP30 | <<locked>> | 80% | 35,433 psi | 56% | 2822 fps | 95.5% |
| Bofors RP5 | <<locked>> | 80% | 44,976 psi | 70% | 3035 fps | 99% |
| Hodgdon H1000 | <<locked>> | 80% | 35,839 psi | 56% | 2825 fps | 96.3% |
| Hodgdon H4831 | <<locked>> | 80% | 46,760 psi | 73% | 3028 fps | 97.9% |
| Hodgdon H4831 SC | <<locked>> | 80% | 45,934 psi | 72% | 3012 fps | 97.7% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 52,736 psi | 83% | 3071 fps | 100% |
| Hodgdon Retumbo | 92.4 gr | 80% | 37,043 psi | 58% | 2943 fps | 97.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,398 psi | 45% | 1880 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 47,558 psi | 75% | 3018 fps | 98.2% |
| IMR 7828 SSC | <<locked>> | 80% | 42,975 psi | 67% | 3012 fps | 97.6% |
| IMR 8133 Enduron | <<locked>> | 88% | 36,825 psi | 58% | 2877 fps | 95.9% |
| Lovex S071 | <<locked>> | 80% | 38,682 psi | 61% | 2815 fps | 99.3% |
| Norma 217 | <<locked>> | 82% | 30,008 psi | 47% | 2700 fps | 95.1% |
| Norma MRP | <<locked>> | 80% | 47,964 psi | 75% | 3114 fps | 99.9% |
| Ramshot Grand | <<locked>> | 80% | 43,265 psi | 68% | 3022 fps | 98% |
| Ramshot Magnum | <<locked>> | 80% | 39,030 psi | 61% | 2887 fps | 98.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,153 psi | 46% | 1923 fps | 100% |
| ReloadSwiss RS 76 | 98.9 gr | 80% | 36,506 psi | 57% | 2913 fps | 98.7% |
| ReloadSwiss RS 80 | <<locked>> | 84% | 39,015 psi | 61% | 2936 fps | 95.2% |
| Rottweil R 904 | <<locked>> | 80% | 49,617 psi | 78% | 3064 fps | 99% |
| Rottweil R 905 | <<locked>> | 80% | 48,486 psi | 76% | 3074 fps | 99.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 48,138 psi | 75% | 3071 fps | 99.4% |
| Somchem S361 | <<locked>> | 80% | 50,734 psi | 80% | 3051 fps | 98.7% |
| Somchem S385 | <<locked>> | 80% | 48,907 psi | 77% | 3045 fps | 99.8% |
| Vihtavuori N165 | <<locked>> | 80% | 42,786 psi | 67% | 2910 fps | 99% |
| Vihtavuori N170 | <<locked>> | 90% | 51,401 psi | 81% | 3100 fps | 95.3% |
| Vihtavuori N555 | <<locked>> | 80% | 48,399 psi | 76% | 3054 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 47,529 psi | 74% | 3107 fps | 98.2% |
| Vihtavuori N565 | <<locked>> | 80% | 39,595 psi | 62% | 2907 fps | 96.3% |
| Vihtavuori N568 | <<locked>> | 84% | 40,147 psi | 63% | 2959 fps | 95% |
| Vihtavuori N570 | 107.8 gr | 90% | 47,413 psi | 74% | 3156 fps | 95.3% |
| Winchester StaBALL HD | <<locked>> | 80% | 42,482 psi | 67% | 3031 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 45,165 psi | 71% | 2969 fps | 99% |
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 | 165gr | Alaska Bullet Works Kodiak SP PSPBC L1.136. Hodgdon Retumbo delivers the highest muzzle velocity at 3,366 fps; across all powders the maximum-charge window runs from 2,093 fps to 3,366 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 165.0 gr projectile in 0.308" calls for a 1:14.5 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. Vihtavuori N570, Hodgdon Retumbo, ReloadSwiss RS 76 rank at the top here: for .30-378 Weath. Mag. with the .308 | 165gr | Alaska Bullet Works Kodiak SP PSPBC L1.136 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.