Load Specifications
Load data in caliber .30-378 Weath. Mag. with .308 | 168gr | Norma Diamond 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% | 55,332 psi | 87% | 3114 fps | 100% |
| Accurate High Country | <<locked>> | 84% | 57,246 psi | 90% | 3278 fps | 99.8% |
| Accurate MAGPRO | <<locked>> | 84% | 54,389 psi | 85% | 3222 fps | 99% |
| ADI AR 2209 | <<locked>> | 84% | 56,318 psi | 88% | 3202 fps | 100% |
| ADI AR 2213 | <<locked>> | 86% | 54,984 psi | 86% | 3219 fps | 99.7% |
| ADI AR 2217 | <<locked>> | 94% | 54,012 psi | 85% | 3196 fps | 99.8% |
| ADI AR 2218 | <<locked>> | 98% | 54,476 psi | 85% | 3310 fps | 98.1% |
| ADI AR 2225 | <<locked>> | 98% | 57,101 psi | 89% | 3281 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 56,478 psi | 89% | 3199 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 55,883 psi | 88% | 3192 fps | 100% |
| Alliant Reloder-22 | <<locked>> | 86% | 55,506 psi | 87% | 3215 fps | 100% |
| Alliant Reloder-23 | <<locked>> | 88% | 57,363 psi | 90% | 3173 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 90% | 54,157 psi | 85% | 3192 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 82% | 54,230 psi | 85% | 3205 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 96% | 56,550 psi | 89% | 3294 fps | 98.2% |
| Alliant Reloder-50ᴾ | <<locked>> | 100% | 56,333 psi | 88% | 3278 fps | 97.7% |
| Baschieri & Pellagri 109 | <<locked>> | 88% | 55,535 psi | 87% | 3173 fps | 98.1% |
| Bofors RP15 | <<locked>> | 88% | 54,940 psi | 86% | 3202 fps | 100% |
| Bofors RP30 | <<locked>> | 92% | 54,099 psi | 85% | 3209 fps | 99.8% |
| Bofors RP5 | <<locked>> | 86% | 55,506 psi | 87% | 3215 fps | 100% |
| Hodgdon H1000 | <<locked>> | 92% | 55,405 psi | 87% | 3219 fps | 100% |
| Hodgdon H4831 | <<locked>> | 86% | 57,653 psi | 90% | 3209 fps | 99.6% |
| Hodgdon H4831 SC | <<locked>> | 86% | 56,681 psi | 89% | 3192 fps | 99.5% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 56,608 psi | 89% | 3104 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 92% | 57,435 psi | 90% | 3353 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 37,797 psi | 59% | 2077 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 84% | 54,288 psi | 85% | 3123 fps | 99.3% |
| IMR 7828 SSC | <<locked>> | 88% | 57,435 psi | 90% | 3268 fps | 99.9% |
| IMR 8133 Enduronᴾ | <<locked>> | 100% | 56,028 psi | 88% | 3258 fps | 99.9% |
| Lovex S071 | <<locked>> | 92% | 57,334 psi | 90% | 3143 fps | 100% |
| Norma 217ᴾ | <<locked>> | 100% | 57,479 psi | 90% | 3281 fps | 100% |
| Norma MRP | <<locked>> | 84% | 55,608 psi | 87% | 3228 fps | 100% |
| Ramshot Grand | <<locked>> | 86% | 54,766 psi | 86% | 3225 fps | 99.8% |
| Ramshot Magnum | <<locked>> | 90% | 57,377 psi | 90% | 3212 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 38,725 psi | 61% | 2123 fps | 100% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 54,114 psi | 85% | 3264 fps | 100% |
| ReloadSwiss RS 80 | <<locked>> | 92% | 53,563 psi | 84% | 3225 fps | 99.1% |
| Rottweil R 904 | <<locked>> | 84% | 56,782 psi | 89% | 3173 fps | 99.8% |
| Rottweil R 905 | <<locked>> | 84% | 55,753 psi | 87% | 3186 fps | 100% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 55,405 psi | 87% | 3179 fps | 100% |
| Somchem S361 | <<locked>> | 82% | 54,578 psi | 86% | 3100 fps | 99.3% |
| Somchem S385 | <<locked>> | 84% | 56,144 psi | 88% | 3150 fps | 100% |
| Vihtavuori N165 | <<locked>> | 88% | 56,130 psi | 88% | 3136 fps | 100% |
| Vihtavuori N170 | <<locked>> | 92% | 55,579 psi | 87% | 3159 fps | 96.5% |
| Vihtavuori N555 | <<locked>> | 84% | 55,608 psi | 87% | 3150 fps | 100% |
| Vihtavuori N560 | <<locked>> | 84% | 54,984 psi | 86% | 3232 fps | 99.4% |
| Vihtavuori N565 | <<locked>> | 90% | 56,260 psi | 88% | 3225 fps | 99.7% |
| Vihtavuori N568 | <<locked>> | 92% | 54,027 psi | 85% | 3232 fps | 98.8% |
| Vihtavuori N570 | <<locked>> | 94% | 55,332 psi | 87% | 3297 fps | 97.6% |
| Winchester StaBALL HD | <<locked>> | 86% | 53,882 psi | 84% | 3209 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 86% | 55,999 psi | 88% | 3146 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% | 45,266 psi | 71% | 2936 fps | 100% |
| Accurate High Country | <<locked>> | 80% | 49,821 psi | 78% | 3146 fps | 99.1% |
| Accurate MAGPRO | <<locked>> | 80% | 47,094 psi | 74% | 3077 fps | 97.7% |
| ADI AR 2209 | <<locked>> | 80% | 49,298 psi | 77% | 3077 fps | 99.6% |
| ADI AR 2213 | <<locked>> | 80% | 44,527 psi | 70% | 3015 fps | 98.1% |
| ADI AR 2217 | <<locked>> | 82% | 35,505 psi | 56% | 2795 fps | 95.6% |
| ADI AR 2218 | <<locked>> | 94% | 47,021 psi | 74% | 3153 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 80% | 30,560 psi | 48% | 2694 fps | 96.6% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 49,603 psi | 78% | 3077 fps | 99.6% |
| Alliant Reloder-19 | <<locked>> | 80% | 49,139 psi | 77% | 3071 fps | 99.6% |
| Alliant Reloder-22 | <<locked>> | 80% | 45,310 psi | 71% | 3022 fps | 99.1% |
| Alliant Reloder-23 | <<locked>> | 80% | 44,034 psi | 69% | 2953 fps | 100% |
| Alliant Reloder-25 | <<locked>> | 80% | 38,276 psi | 60% | 2887 fps | 99.8% |
| Alliant Reloder-26 | <<locked>> | 80% | 50,270 psi | 79% | 3136 fps | 100% |
| Alliant Reloder-33 | <<locked>> | 90% | 44,991 psi | 71% | 3064 fps | 95.2% |
| Alliant Reloder-50 | <<locked>> | 96% | 48,457 psi | 76% | 3130 fps | 95.8% |
| Baschieri & Pellagri 109 | <<locked>> | 82% | 45,658 psi | 72% | 2982 fps | 95.8% |
| Bofors RP15 | <<locked>> | 80% | 42,148 psi | 66% | 2949 fps | 98.4% |
| Bofors RP30 | <<locked>> | 80% | 35,752 psi | 56% | 2812 fps | 95.8% |
| Bofors RP5 | <<locked>> | 80% | 45,310 psi | 71% | 3022 fps | 99.1% |
| Hodgdon H1000 | <<locked>> | 80% | 36,143 psi | 57% | 2815 fps | 96.6% |
| Hodgdon H4831 | <<locked>> | 80% | 47,079 psi | 74% | 3015 fps | 98.1% |
| Hodgdon H4831 SC | <<locked>> | 80% | 46,238 psi | 72% | 2999 fps | 97.9% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 53,026 psi | 83% | 3051 fps | 100% |
| Hodgdon Retumbo | 91.9 gr | 80% | 37,391 psi | 59% | 2933 fps | 98.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 28,384 psi | 44% | 1860 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 80% | 47,819 psi | 75% | 3002 fps | 98.4% |
| IMR 7828 SSC | <<locked>> | 80% | 43,294 psi | 68% | 2995 fps | 97.9% |
| IMR 8133 Enduron | <<locked>> | 86% | 34,621 psi | 54% | 2799 fps | 95.1% |
| Lovex S071 | <<locked>> | 80% | 38,943 psi | 61% | 2802 fps | 99.4% |
| Norma 217 | <<locked>> | 82% | 30,298 psi | 47% | 2694 fps | 95.5% |
| Norma MRP | <<locked>> | 80% | 48,356 psi | 76% | 3100 fps | 100% |
| Ramshot Grand | <<locked>> | 80% | 43,671 psi | 68% | 3012 fps | 98.3% |
| Ramshot Magnum | <<locked>> | 80% | 39,262 psi | 62% | 2874 fps | 98.6% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 29,138 psi | 46% | 1906 fps | 100% |
| ReloadSwiss RS 76 | 98.3 gr | 80% | 36,753 psi | 58% | 2904 fps | 98.9% |
| ReloadSwiss RS 80 | <<locked>> | 84% | 39,465 psi | 62% | 2930 fps | 95.6% |
| Rottweil R 904 | <<locked>> | 80% | 49,893 psi | 78% | 3048 fps | 99.1% |
| Rottweil R 905 | <<locked>> | 80% | 48,820 psi | 77% | 3061 fps | 99.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 80% | 48,472 psi | 76% | 3058 fps | 99.6% |
| Somchem S361 | <<locked>> | 80% | 50,952 psi | 80% | 3035 fps | 98.8% |
| Somchem S385 | <<locked>> | 80% | 49,226 psi | 77% | 3031 fps | 99.9% |
| Vihtavuori N165 | <<locked>> | 80% | 43,062 psi | 67% | 2897 fps | 99.1% |
| Vihtavuori N170 | <<locked>> | 90% | 51,895 psi | 81% | 3091 fps | 95.6% |
| Vihtavuori N555 | <<locked>> | 80% | 48,718 psi | 76% | 3038 fps | 100% |
| Vihtavuori N560 | <<locked>> | 80% | 47,906 psi | 75% | 3094 fps | 98.4% |
| Vihtavuori N565 | <<locked>> | 80% | 39,914 psi | 63% | 2894 fps | 96.5% |
| Vihtavuori N568 | <<locked>> | 84% | 40,451 psi | 63% | 2946 fps | 95.3% |
| Vihtavuori N570 | 107.3 gr | 90% | 47,950 psi | 75% | 3150 fps | 95.7% |
| Winchester StaBALL HD | <<locked>> | 80% | 42,917 psi | 67% | 3018 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 80% | 45,484 psi | 71% | 2956 fps | 99.1% |
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 | 168gr | Norma Diamond. Hodgdon Retumbo delivers the highest muzzle velocity at 3,353 fps; across all powders the maximum-charge window runs from 2,077 fps to 3,353 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 168.0 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. Vihtavuori N570, Hodgdon Retumbo, ReloadSwiss RS 76 rank at the top here: for .30-378 Weath. Mag. with the .308 | 168gr | Norma Diamond 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.