Load Specifications
Bullet:.375 | 240gr | Atomic 29 HP
Bullet Manufacturer:Atomic 29
Bullet Weight:240 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 | 240gr | Atomic 29 HP bullet and 106 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 60, Hodgdon H414 and ReloadSwiss RS 70.
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>> | 84% | 55,796 psi | 87% | 2933 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 54,172 psi | 85% | 2956 fps | 98.5% |
| Accurate 3100ᴾ | <<locked>> | 100% | 51,256 psi | 80% | 2989 fps | 99.3% |
| Accurate 4064 | <<locked>> | 86% | 56,217 psi | 88% | 2989 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 57,406 psi | 90% | 3107 fps | 100% |
| Accurate High Countryᴾ | <<locked>> | 100% | 56,391 psi | 88% | 3202 fps | 97.6% |
| ADI AR 2206H | <<locked>> | 82% | 55,695 psi | 87% | 3025 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 56,985 psi | 89% | 3031 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 55,042 psi | 86% | 3097 fps | 98.1% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 52,634 psi | 82% | 3081 fps | 96.3% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 56,333 psi | 88% | 3163 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 54,882 psi | 86% | 3087 fps | 98.1% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 54,882 psi | 86% | 3087 fps | 98.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 57,638 psi | 90% | 3054 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 54,288 psi | 85% | 3022 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 54,534 psi | 85% | 3110 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 55,898 psi | 88% | 3136 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 54,114 psi | 85% | 3077 fps | 98% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 51,242 psi | 80% | 3077 fps | 97.7% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 48,312 psi | 76% | 3012 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 42,047 psi | 66% | 2923 fps | 98.6% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 55,637 psi | 87% | 3215 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 55,854 psi | 88% | 3045 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 46,934 psi | 74% | 2995 fps | 96.5% |
| Bofors RP3 | <<locked>> | 86% | 54,694 psi | 86% | 3015 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 51,242 psi | 80% | 3077 fps | 97.7% |
| Bofors RP7 | <<locked>> | 90% | 54,433 psi | 85% | 3002 fps | 98.7% |
| Hodgdon H380 | <<locked>> | 86% | 55,245 psi | 87% | 3031 fps | 100% |
| Hodgdon H414 | <<locked>> | 92% | 56,028 psi | 88% | 3104 fps | 99.3% |
| Hodgdon H4350 | <<locked>> | 90% | 55,970 psi | 88% | 3064 fps | 98.5% |
| Hodgdon H4831ᴾ | <<locked>> | 100% | 56,521 psi | 89% | 3087 fps | 96.5% |
| Hodgdon H4831 SCᴾ | <<locked>> | 100% | 55,332 psi | 87% | 3068 fps | 96.3% |
| Hodgdon H4895 | <<locked>> | 82% | 56,318 psi | 88% | 3035 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 54,795 psi | 86% | 3028 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 56,710 psi | 89% | 3071 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 56,608 psi | 89% | 3146 fps | 99.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,114 psi | 57% | 1883 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 57,464 psi | 90% | 3035 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 56,927 psi | 89% | 3009 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 56,333 psi | 88% | 3012 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 55,622 psi | 87% | 2995 fps | 99.2% |
| IMR 4350 | <<locked>> | 94% | 55,332 psi | 87% | 3035 fps | 98.9% |
| IMR 4451 Enduron | <<locked>> | 90% | 56,173 psi | 88% | 3031 fps | 99.2% |
| IMR 4831 | <<locked>> | 94% | 54,128 psi | 85% | 3041 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 55,680 psi | 87% | 3051 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 54,607 psi | 86% | 3018 fps | 96.3% |
| Lovex D073.6 | <<locked>> | 82% | 55,970 psi | 88% | 2995 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 54,621 psi | 86% | 2946 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 56,318 psi | 88% | 3002 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 55,985 psi | 88% | 3022 fps | 99.8% |
| Lovex S070 | <<locked>> | 94% | 57,246 psi | 90% | 3064 fps | 99.5% |
| Lovex S071ᴾ | <<locked>> | 100% | 42,264 psi | 66% | 2825 fps | 97.9% |
| Norma 201 | <<locked>> | 82% | 54,230 psi | 85% | 2963 fps | 100% |
| Norma 202 | <<locked>> | 82% | 55,013 psi | 86% | 2963 fps | 100% |
| Norma 203B | <<locked>> | 86% | 57,232 psi | 90% | 3064 fps | 100% |
| Norma 204 | <<locked>> | 94% | 56,217 psi | 88% | 3091 fps | 98.1% |
| Norma MRPᴾ | <<locked>> | 100% | 54,462 psi | 85% | 3166 fps | 99.2% |
| Norma URP | <<locked>> | 94% | 56,028 psi | 88% | 3087 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 54,346 psi | 85% | 3035 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 50,256 psi | 79% | 3061 fps | 96.2% |
| Ramshot Hunter | <<locked>> | 94% | 54,955 psi | 86% | 3091 fps | 99.7% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 44,614 psi | 70% | 2927 fps | 96.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,666 psi | 57% | 1929 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 55,347 psi | 87% | 3018 fps | 99.5% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 55,303 psi | 87% | 3094 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 55,477 psi | 87% | 3130 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 57,392 psi | 90% | 3130 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 56,072 psi | 88% | 3163 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 40,988 psi | 64% | 2933 fps | 96.5% |
| Rottweil R 902 | <<locked>> | 84% | 54,969 psi | 86% | 2966 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 54,723 psi | 86% | 3012 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 56,739 psi | 89% | 3061 fps | 97.3% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 56,942 psi | 89% | 3123 fps | 98.5% |
| Rottweil R 907 | <<locked>> | 90% | 54,433 psi | 85% | 3002 fps | 98.7% |
| Shooters World Long Rifle | <<locked>> | 92% | 55,985 psi | 88% | 3022 fps | 99.8% |
| Shooters World Match Rifle | <<locked>> | 82% | 55,970 psi | 88% | 2995 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 56,318 psi | 88% | 3002 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 57,246 psi | 90% | 3064 fps | 99.5% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 56,724 psi | 89% | 3074 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 57,058 psi | 89% | 3031 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 54,215 psi | 85% | 2995 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 55,216 psi | 87% | 2890 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 56,289 psi | 88% | 2897 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 55,912 psi | 88% | 2976 fps | 99.2% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 56,434 psi | 88% | 3117 fps | 98.5% |
| Somchem S335 | <<locked>> | 82% | 54,853 psi | 86% | 2890 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 56,797 psi | 89% | 3015 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 54,940 psi | 86% | 3009 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 54,940 psi | 86% | 2995 fps | 96.1% |
| Somchem S365 | <<locked>> | 96% | 55,143 psi | 86% | 3087 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 57,653 psi | 90% | 3097 fps | 99.1% |
| Vihtavuori N133 | <<locked>> | 82% | 55,796 psi | 87% | 2874 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 55,201 psi | 87% | 2920 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 55,666 psi | 87% | 2940 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 56,260 psi | 88% | 2979 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 54,766 psi | 86% | 3031 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 49,777 psi | 78% | 2953 fps | 97.7% |
| Vihtavuori N540 | <<locked>> | 86% | 57,377 psi | 90% | 2986 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 57,479 psi | 90% | 3091 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 53,998 psi | 85% | 3091 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 54,897 psi | 86% | 3153 fps | 96.6% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 54,592 psi | 86% | 2995 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 56,217 psi | 88% | 3107 fps | 99.4% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 43,410 psi | 68% | 3061 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 54,302 psi | 85% | 3002 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 54,201 psi | 85% | 3031 fps | 97.9% |
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% | 48,776 psi | 76% | 2831 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 47,297 psi | 74% | 2835 fps | 97.3% |
| Accurate 3100 | <<locked>> | 88% | 33,547 psi | 53% | 2628 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 46,253 psi | 72% | 2838 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 34,998 psi | 55% | 2684 fps | 97.4% |
| Accurate High Country | <<locked>> | 94% | 45,426 psi | 71% | 3002 fps | 95% |
| ADI AR 2206H | <<locked>> | 80% | 52,286 psi | 82% | 2972 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 44,280 psi | 69% | 2815 fps | 99.6% |
| ADI AR 2209 | <<locked>> | 92% | 45,005 psi | 71% | 2910 fps | 95.8% |
| ADI AR 2213 | <<locked>> | 98% | 49,081 psi | 77% | 3015 fps | 95.4% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 48,849 psi | 77% | 3038 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 42,134 psi | 66% | 2848 fps | 95% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 42,134 psi | 66% | 2848 fps | 95% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 44,527 psi | 70% | 2838 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 47,747 psi | 75% | 2913 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 80% | 34,519 psi | 54% | 2700 fps | 97.6% |
| Alliant Reloder-17 | <<locked>> | 80% | 39,073 psi | 61% | 2831 fps | 99.7% |
| Alliant Reloder-19 | <<locked>> | 92% | 44,541 psi | 70% | 2900 fps | 95.8% |
| Alliant Reloder-22 | <<locked>> | 94% | 41,727 psi | 65% | 2887 fps | 95.1% |
| Alliant Reloder-23 | <<locked>> | 82% | 26,643 psi | 42% | 2487 fps | 95.7% |
| Alliant Reloder-25 | <<locked>> | 92% | 32,401 psi | 51% | 2671 fps | 95% |
| Alliant Reloder-26 | <<locked>> | 84% | 30,647 psi | 48% | 2667 fps | 95.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 52,156 psi | 82% | 2986 fps | 100% |
| Bofors RP15 | <<locked>> | 98% | 43,903 psi | 69% | 2933 fps | 95.7% |
| Bofors RP3 | <<locked>> | 80% | 44,585 psi | 70% | 2848 fps | 100% |
| Bofors RP5 | <<locked>> | 94% | 41,727 psi | 65% | 2887 fps | 95.1% |
| Bofors RP7 | <<locked>> | 80% | 39,436 psi | 62% | 2710 fps | 95.4% |
| Hodgdon H380 | <<locked>> | 80% | 45,150 psi | 71% | 2858 fps | 99.2% |
| Hodgdon H414 | 91.6 gr | 80% | 37,217 psi | 58% | 2736 fps | 95.3% |
| Hodgdon H4350 | <<locked>> | 82% | 43,091 psi | 68% | 2825 fps | 95.7% |
| Hodgdon H4831 | <<locked>> | 98% | 52,692 psi | 83% | 3025 fps | 95.7% |
| Hodgdon H4831 SC | <<locked>> | 98% | 51,576 psi | 81% | 3005 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 52,852 psi | 83% | 2982 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 32,010 psi | 50% | 2589 fps | 98.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 49,356 psi | 77% | 2959 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 38,986 psi | 61% | 2808 fps | 95.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,919 psi | 42% | 1686 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 50,604 psi | 79% | 2930 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 53,388 psi | 84% | 2959 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 46,528 psi | 73% | 2848 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 80% | 48,907 psi | 77% | 2881 fps | 98.3% |
| IMR 4350 | <<locked>> | 84% | 40,176 psi | 63% | 2746 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 80% | 41,017 psi | 64% | 2746 fps | 96.4% |
| IMR 4831 | <<locked>> | 80% | 33,808 psi | 53% | 2638 fps | 97.1% |
| IMR 4895 | <<locked>> | 80% | 48,994 psi | 77% | 2940 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 51,097 psi | 80% | 2959 fps | 95.5% |
| Lovex D073.6 | <<locked>> | 80% | 52,315 psi | 82% | 2940 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 51,285 psi | 80% | 2894 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 46,615 psi | 73% | 2848 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 38,319 psi | 60% | 2690 fps | 97.1% |
| Lovex S070 | <<locked>> | 80% | 36,550 psi | 57% | 2664 fps | 95.3% |
| Lovex S071 | <<locked>> | 94% | 34,635 psi | 54% | 2657 fps | 95.6% |
| Norma 201 | <<locked>> | 80% | 50,821 psi | 80% | 2910 fps | 100% |
| Norma 202 | <<locked>> | 80% | 51,605 psi | 81% | 2910 fps | 100% |
| Norma 203B | <<locked>> | 80% | 47,108 psi | 74% | 2897 fps | 100% |
| Norma 204 | <<locked>> | 86% | 42,641 psi | 67% | 2838 fps | 95% |
| Norma MRP | <<locked>> | 90% | 38,232 psi | 60% | 2838 fps | 95.5% |
| Norma URP | <<locked>> | 80% | 35,099 psi | 55% | 2684 fps | 97.3% |
| Ramshot Big Game | <<locked>> | 80% | 47,398 psi | 74% | 2920 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 46,557 psi | 73% | 2989 fps | 95.2% |
| Ramshot Hunter | <<locked>> | 80% | 34,084 psi | 53% | 2664 fps | 95.1% |
| Ramshot Magnum | <<locked>> | 98% | 41,336 psi | 65% | 2854 fps | 95.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,369 psi | 43% | 1726 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 45,411 psi | 71% | 2844 fps | 98.1% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 51,561 psi | 81% | 3035 fps | 100% |
| ReloadSwiss RS 60 | 93.6 gr | 80% | 41,611 psi | 65% | 2894 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 34,795 psi | 55% | 2700 fps | 97% |
| ReloadSwiss RS 70 | 95.1 gr | 80% | 34,171 psi | 54% | 2707 fps | 96.3% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 38,145 psi | 60% | 2861 fps | 95.3% |
| Rottweil R 902 | <<locked>> | 80% | 48,457 psi | 76% | 2861 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 41,945 psi | 66% | 2789 fps | 99.9% |
| Rottweil R 904 | <<locked>> | 92% | 46,630 psi | 73% | 2884 fps | 95% |
| Rottweil R 905 | <<locked>> | 92% | 43,439 psi | 68% | 2881 fps | 95.7% |
| Rottweil R 907 | <<locked>> | 80% | 39,436 psi | 62% | 2710 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 38,319 psi | 60% | 2690 fps | 97.1% |
| Shooters World Match Rifle | <<locked>> | 80% | 52,315 psi | 82% | 2940 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 46,615 psi | 73% | 2848 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 36,550 psi | 57% | 2664 fps | 95.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 43,323 psi | 68% | 2848 fps | 99.7% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 53,200 psi | 83% | 2972 fps | 99.8% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 50,792 psi | 80% | 2940 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 51,880 psi | 81% | 2844 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 43,685 psi | 68% | 2707 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 37,579 psi | 59% | 2631 fps | 95.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 43,033 psi | 67% | 2874 fps | 95.6% |
| Somchem S335 | <<locked>> | 80% | 51,532 psi | 81% | 2841 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 53,011 psi | 83% | 2959 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 42,409 psi | 66% | 2789 fps | 99.8% |
| Somchem S361 | <<locked>> | 94% | 51,285 psi | 80% | 2936 fps | 95.3% |
| Somchem S365 | <<locked>> | 80% | 31,531 psi | 49% | 2635 fps | 99.2% |
| Somchem S385 | <<locked>> | 88% | 38,537 psi | 60% | 2743 fps | 95.1% |
| Vihtavuori N133 | <<locked>> | 80% | 52,460 psi | 82% | 2828 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 48,588 psi | 76% | 2825 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 48,994 psi | 77% | 2841 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 40,538 psi | 64% | 2720 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 36,535 psi | 57% | 2687 fps | 97.7% |
| Vihtavuori N165 | <<locked>> | 94% | 40,582 psi | 64% | 2776 fps | 95.3% |
| Vihtavuori N540 | <<locked>> | 80% | 47,268 psi | 74% | 2831 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 35,955 psi | 56% | 2684 fps | 97.4% |
| Vihtavuori N555 | <<locked>> | 82% | 29,167 psi | 46% | 2566 fps | 95.8% |
| Vihtavuori N560 | <<locked>> | 98% | 51,213 psi | 80% | 3087 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 35,897 psi | 56% | 2657 fps | 99.3% |
| Winchester 760 | <<locked>> | 80% | 37,333 psi | 59% | 2740 fps | 95.4% |
| Winchester StaBALL HD | <<locked>> | 84% | 25,063 psi | 39% | 2507 fps | 95.2% |
| Winchester StaBALL Match | <<locked>> | 80% | 50,676 psi | 79% | 2946 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 43,801 psi | 69% | 2848 fps | 95.5% |
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 106 powders for .378 Weath. Mag. loaded with the .375 | 240gr | Atomic 29 HP. Alliant Reloder-26 delivers the highest muzzle velocity at 3,215 fps; across all powders the maximum-charge window runs from 1,883 fps to 3,215 fps. Accurate 3100 gives the best case fill at 100 %, and 106 of the 106 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 240.0 gr projectile in 0.375" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate High Country, 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 60, Hodgdon H414, ReloadSwiss RS 70 rank at the top here: for .378 Weath. Mag. with the .375 | 240gr | Atomic 29 HP 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.