Load Specifications
Bullet Manufacturer:Frontier Bullets
Bullet Weight:250 gr
Bullet Diameter:0.375"
Bullet Length:<<locked>>
Caliber:.378 Weath. Mag. load data
Case Length (l3):2.913"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:137 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:26"
Max. allowed Pressure:63,817 psi
Recommended Twist Rate:1:6.0
Load data in caliber .378 Weath. Mag. with .375 | 250gr | Frontier PH HPFB bullet and 102 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Alliant Reloder-26 and Accurate High Country.
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.
A valid access license is required to use the Personalized Load Calculator.
You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 82% | 55,129 psi | 86% | 2854 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 56,333 psi | 88% | 2927 fps | 99% |
| Accurate 3100ᴾ | <<locked>> | 100% | 54,128 psi | 85% | 2972 fps | 99.7% |
| Accurate 4064 | <<locked>> | 84% | 55,492 psi | 87% | 2910 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 56,333 psi | 88% | 3025 fps | 100% |
| Accurate High Country | <<locked>> | 98% | 55,259 psi | 87% | 3120 fps | 97.8% |
| Accurate MAGPROᴾ | <<locked>> | 100% | 56,347 psi | 88% | 3120 fps | 96.7% |
| ADI AR 2206H | <<locked>> | 82% | 57,740 psi | 90% | 2989 fps | 100% |
| ADI AR 2208 | <<locked>> | 86% | 55,593 psi | 87% | 2946 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 57,246 psi | 90% | 3071 fps | 98.7% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 54,911 psi | 86% | 3064 fps | 97.2% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 54,868 psi | 86% | 3074 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 57,319 psi | 90% | 3068 fps | 98.7% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 57,319 psi | 90% | 3068 fps | 98.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 56,333 psi | 88% | 2969 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 56,666 psi | 89% | 2992 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 56,942 psi | 89% | 3081 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 54,563 psi | 86% | 3051 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 56,507 psi | 89% | 3058 fps | 98.6% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 53,737 psi | 84% | 3058 fps | 98.4% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 50,749 psi | 80% | 2989 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 44,193 psi | 69% | 2913 fps | 99.3% |
| Alliant Reloder-26 | <<locked>> | 98% | 54,447 psi | 85% | 3133 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 49,255 psi | 77% | 2979 fps | 97.5% |
| Bofors RP3 | <<locked>> | 86% | 57,348 psi | 90% | 2986 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 53,737 psi | 84% | 3058 fps | 98.4% |
| Bofors RP7 | <<locked>> | 90% | 56,492 psi | 89% | 2972 fps | 99.2% |
| Hodgdon H380 | <<locked>> | 86% | 57,624 psi | 90% | 3005 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 54,853 psi | 86% | 3022 fps | 99.4% |
| Hodgdon H4350 | <<locked>> | 88% | 54,563 psi | 86% | 2979 fps | 98.5% |
| Hodgdon H4831 | <<locked>> | 98% | 55,056 psi | 86% | 3005 fps | 96.6% |
| Hodgdon H4831 SCᴾ | <<locked>> | 100% | 57,638 psi | 90% | 3048 fps | 97.1% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 57,217 psi | 90% | 2995 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 55,274 psi | 87% | 2989 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 43,250 psi | 68% | 2943 fps | 96.7% |
| Hodgdon Superformance | <<locked>> | 90% | 54,998 psi | 86% | 3061 fps | 99.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,405 psi | 57% | 1847 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 55,985 psi | 88% | 2949 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 54,969 psi | 86% | 2927 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 57,682 psi | 90% | 2966 fps | 99.6% |
| IMR 4350 | <<locked>> | 94% | 57,479 psi | 90% | 3005 fps | 99.3% |
| IMR 4451 Enduron | <<locked>> | 88% | 54,752 psi | 86% | 2946 fps | 99.3% |
| IMR 4831 | <<locked>> | 94% | 56,666 psi | 89% | 3012 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 54,433 psi | 85% | 2966 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 56,623 psi | 89% | 2992 fps | 97.1% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 52,330 psi | 82% | 3035 fps | 96.9% |
| Lovex S060 | <<locked>> | 82% | 56,521 psi | 89% | 2910 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 55,158 psi | 86% | 2920 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 54,839 psi | 86% | 2943 fps | 99.8% |
| Lovex S070 | <<locked>> | 92% | 56,188 psi | 88% | 2986 fps | 99.6% |
| Lovex S071ᴾ | <<locked>> | 100% | 44,962 psi | 70% | 2818 fps | 98.7% |
| Norma 201 | <<locked>> | 82% | 56,565 psi | 89% | 2933 fps | 100% |
| Norma 202 | <<locked>> | 82% | 57,276 psi | 90% | 2927 fps | 100% |
| Norma 203B | <<locked>> | 84% | 55,927 psi | 88% | 2979 fps | 100% |
| Norma 204 | <<locked>> | 92% | 54,781 psi | 86% | 3005 fps | 98.2% |
| Norma MRPᴾ | <<locked>> | 100% | 57,261 psi | 90% | 3146 fps | 99.7% |
| Norma URP | <<locked>> | 92% | 54,984 psi | 86% | 3009 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 56,724 psi | 89% | 3005 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 52,736 psi | 83% | 3048 fps | 97.3% |
| Ramshot Hunter | <<locked>> | 94% | 57,435 psi | 90% | 3068 fps | 99.9% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 46,920 psi | 74% | 2917 fps | 97.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,043 psi | 58% | 1890 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 57,595 psi | 90% | 2992 fps | 99.8% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 57,740 psi | 90% | 3064 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 54,056 psi | 85% | 3041 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 56,115 psi | 88% | 3048 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 54,636 psi | 86% | 3077 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 43,192 psi | 68% | 2936 fps | 97.8% |
| Rottweil R 902 | <<locked>> | 84% | 57,145 psi | 90% | 2930 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 57,334 psi | 90% | 2982 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 55,303 psi | 87% | 2979 fps | 97.4% |
| Rottweil R 905 | <<locked>> | 98% | 55,796 psi | 87% | 3045 fps | 98.7% |
| Rottweil R 907 | <<locked>> | 90% | 56,492 psi | 89% | 2972 fps | 99.2% |
| Shooters World Long Rifle | <<locked>> | 90% | 54,839 psi | 86% | 2943 fps | 99.8% |
| Shooters World Precision | <<locked>> | 84% | 55,158 psi | 86% | 2920 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 56,188 psi | 88% | 2986 fps | 99.6% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 55,361 psi | 87% | 2992 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 56,275 psi | 88% | 2963 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 57,188 psi | 90% | 2854 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 54,781 psi | 86% | 2812 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 54,563 psi | 86% | 2894 fps | 99.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 55,303 psi | 87% | 3038 fps | 98.6% |
| Somchem S335 | <<locked>> | 82% | 57,000 psi | 89% | 2854 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 57,276 psi | 90% | 2979 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 57,203 psi | 90% | 2972 fps | 97% |
| Somchem S365 | <<locked>> | 94% | 54,172 psi | 85% | 3009 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 56,492 psi | 89% | 3018 fps | 99.2% |
| Vihtavuori N133 | <<locked>> | 82% | 57,725 psi | 90% | 2835 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 57,551 psi | 90% | 2884 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 54,418 psi | 85% | 2854 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 55,027 psi | 86% | 2897 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 57,101 psi | 89% | 3002 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 52,098 psi | 82% | 2933 fps | 98.4% |
| Vihtavuori N540 | <<locked>> | 84% | 56,057 psi | 88% | 2900 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 56,202 psi | 88% | 3009 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 56,942 psi | 89% | 3071 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 57,508 psi | 90% | 3136 fps | 97.5% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 56,797 psi | 89% | 2966 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 55,013 psi | 86% | 3025 fps | 99.4% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 45,934 psi | 72% | 3051 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 56,565 psi | 89% | 2969 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 56,695 psi | 89% | 3012 fps | 98.6% |
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 2495 | <<locked>> | 80% | 51,634 psi | 81% | 2805 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 49,400 psi | 77% | 2815 fps | 98% |
| Accurate 3100 | <<locked>> | 86% | 33,634 psi | 53% | 2575 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 48,936 psi | 77% | 2812 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 37,275 psi | 58% | 2680 fps | 98.4% |
| Accurate High Country | 106 gr | 92% | 44,773 psi | 70% | 2930 fps | 95.3% |
| Accurate MAGPRO | <<locked>> | 98% | 52,359 psi | 82% | 3054 fps | 95.8% |
| ADI AR 2206H | <<locked>> | 80% | 54,244 psi | 85% | 2936 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 46,108 psi | 72% | 2789 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 88% | 41,263 psi | 65% | 2772 fps | 95.1% |
| ADI AR 2213 | <<locked>> | 96% | 48,066 psi | 75% | 2940 fps | 95.6% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 51,039 psi | 80% | 3012 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 41,466 psi | 65% | 2776 fps | 95.3% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 41,466 psi | 65% | 2776 fps | 95.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 46,659 psi | 73% | 2815 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 49,777 psi | 78% | 2884 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,318 psi | 57% | 2690 fps | 98.5% |
| Alliant Reloder-17 | <<locked>> | 80% | 41,249 psi | 65% | 2818 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 41,002 psi | 64% | 2769 fps | 95.2% |
| Alliant Reloder-22 | <<locked>> | 92% | 41,162 psi | 65% | 2818 fps | 95.4% |
| Alliant Reloder-23 | <<locked>> | 80% | 26,672 psi | 42% | 2438 fps | 96.3% |
| Alliant Reloder-25 | <<locked>> | 90% | 32,184 psi | 50% | 2615 fps | 95.5% |
| Alliant Reloder-26 | 97.3 gr | 82% | 30,414 psi | 48% | 2608 fps | 95.6% |
| Bofors RP15 | <<locked>> | 94% | 40,611 psi | 64% | 2805 fps | 95.1% |
| Bofors RP3 | <<locked>> | 80% | 47,007 psi | 74% | 2825 fps | 100% |
| Bofors RP5 | <<locked>> | 92% | 41,162 psi | 65% | 2818 fps | 95.4% |
| Bofors RP7 | <<locked>> | 80% | 41,365 psi | 65% | 2694 fps | 96.4% |
| Hodgdon H380 | <<locked>> | 80% | 47,427 psi | 74% | 2838 fps | 99.6% |
| Hodgdon H414 | <<locked>> | 80% | 39,218 psi | 61% | 2726 fps | 96.4% |
| Hodgdon H4350 | <<locked>> | 80% | 42,206 psi | 66% | 2749 fps | 95.9% |
| Hodgdon H4831 | <<locked>> | 94% | 48,080 psi | 75% | 2884 fps | 95% |
| Hodgdon H4831 SC | <<locked>> | 96% | 50,430 psi | 79% | 2927 fps | 95.6% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 33,953 psi | 53% | 2582 fps | 99% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 51,706 psi | 81% | 2933 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 40,567 psi | 64% | 2877 fps | 95.6% |
| Hodgdon Superformance | <<locked>> | 80% | 38,159 psi | 60% | 2733 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,238 psi | 43% | 1650 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 52,417 psi | 82% | 2894 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 48,472 psi | 76% | 2822 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 50,792 psi | 80% | 2854 fps | 98.8% |
| IMR 4350 | <<locked>> | 80% | 37,101 psi | 58% | 2618 fps | 95% |
| IMR 4451 Enduron | <<locked>> | 80% | 42,815 psi | 67% | 2726 fps | 97.2% |
| IMR 4831 | <<locked>> | 80% | 35,911 psi | 56% | 2631 fps | 98.1% |
| IMR 4895 | <<locked>> | 80% | 51,082 psi | 80% | 2913 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 49,922 psi | 78% | 2881 fps | 95.7% |
| IMR 7828 SSC | <<locked>> | 96% | 45,847 psi | 72% | 2910 fps | 95.1% |
| Lovex S060 | <<locked>> | 80% | 53,098 psi | 83% | 2861 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 48,747 psi | 76% | 2818 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 40,306 psi | 63% | 2674 fps | 97.9% |
| Lovex S070 | <<locked>> | 80% | 38,595 psi | 60% | 2657 fps | 96.4% |
| Lovex S071 | <<locked>> | 90% | 32,605 psi | 51% | 2549 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 53,055 psi | 83% | 2881 fps | 100% |
| Norma 202 | <<locked>> | 80% | 53,780 psi | 84% | 2877 fps | 100% |
| Norma 203B | <<locked>> | 80% | 49,153 psi | 77% | 2871 fps | 100% |
| Norma 204 | <<locked>> | 84% | 41,785 psi | 65% | 2762 fps | 95.2% |
| Norma MRP | <<locked>> | 88% | 37,739 psi | 59% | 2769 fps | 95.8% |
| Norma URP | <<locked>> | 80% | 37,159 psi | 58% | 2674 fps | 98.3% |
| Ramshot Big Game | <<locked>> | 80% | 49,516 psi | 78% | 2894 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 45,672 psi | 72% | 2917 fps | 95.4% |
| Ramshot Hunter | <<locked>> | 80% | 35,955 psi | 56% | 2657 fps | 96.3% |
| Ramshot Magnum | <<locked>> | 96% | 40,654 psi | 64% | 2789 fps | 96% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,644 psi | 43% | 1690 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 47,384 psi | 74% | 2822 fps | 98.8% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 53,911 psi | 84% | 3005 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 43,830 psi | 69% | 2874 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 37,086 psi | 58% | 2697 fps | 98.1% |
| ReloadSwiss RS 70 | 94.1 gr | 80% | 36,013 psi | 56% | 2703 fps | 97.5% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 37,594 psi | 59% | 2795 fps | 95.6% |
| Rottweil R 902 | <<locked>> | 80% | 50,676 psi | 79% | 2831 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 44,280 psi | 69% | 2772 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 45,745 psi | 72% | 2812 fps | 95.2% |
| Rottweil R 905 | <<locked>> | 88% | 39,958 psi | 63% | 2749 fps | 95.1% |
| Rottweil R 907 | <<locked>> | 80% | 41,365 psi | 65% | 2694 fps | 96.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,306 psi | 63% | 2674 fps | 97.9% |
| Shooters World Precision | <<locked>> | 80% | 48,747 psi | 76% | 2818 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 38,595 psi | 60% | 2657 fps | 96.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 45,324 psi | 71% | 2825 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 52,765 psi | 83% | 2907 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 53,795 psi | 84% | 2808 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 45,498 psi | 71% | 2674 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 39,421 psi | 62% | 2618 fps | 96.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 42,322 psi | 66% | 2802 fps | 95.8% |
| Somchem S335 | <<locked>> | 80% | 53,592 psi | 84% | 2805 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 44,527 psi | 70% | 2769 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 50,067 psi | 78% | 2858 fps | 95.4% |
| Somchem S365 | <<locked>> | 80% | 33,591 psi | 53% | 2631 fps | 99.7% |
| Somchem S385 | <<locked>> | 86% | 38,101 psi | 60% | 2677 fps | 95.4% |
| Vihtavuori N133 | <<locked>> | 80% | 54,346 psi | 85% | 2789 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 50,778 psi | 80% | 2792 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 51,068 psi | 80% | 2808 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 42,583 psi | 67% | 2697 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 38,464 psi | 60% | 2671 fps | 98.5% |
| Vihtavuori N165 | <<locked>> | 92% | 40,016 psi | 63% | 2707 fps | 95.6% |
| Vihtavuori N540 | <<locked>> | 80% | 49,356 psi | 77% | 2802 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 38,014 psi | 60% | 2677 fps | 98.3% |
| Vihtavuori N555 | <<locked>> | 80% | 29,312 psi | 46% | 2516 fps | 96.4% |
| Vihtavuori N560 | <<locked>> | 94% | 46,833 psi | 73% | 2946 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 37,710 psi | 59% | 2641 fps | 99.7% |
| Winchester 760 | <<locked>> | 80% | 39,320 psi | 62% | 2726 fps | 96.5% |
| Winchester StaBALL HD | <<locked>> | 82% | 25,150 psi | 39% | 2467 fps | 96.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 52,823 psi | 83% | 2913 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 42,873 psi | 67% | 2772 fps | 95.7% |
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 102 powders for .378 Weath. Mag. loaded with the .375 | 250gr | Frontier PH HPFB. Norma MRP delivers the highest muzzle velocity at 3,146 fps; across all powders the maximum-charge window runs from 1,847 fps to 3,146 fps. Accurate 3100 gives the best case fill at 100 %, and 102 of the 102 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.375" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate MAGPRO, ADI AR 2213 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. ReloadSwiss RS 70, Alliant Reloder-26, Accurate High Country rank at the top here: for .378 Weath. Mag. with the .375 | 250gr | Frontier PH HPFB 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.