Load Specifications
Load data in caliber .375 Weath. Mag. with .375 | 245gr | Reichenberg HDB Universal bullet and 96 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Power Pro 2000-MR, ReloadSwiss RS 52 and Hodgdon LEVERevolution.
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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You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 90% | 56,898 psi | 89% | 2726 fps | 100% |
| Accurate 2200 | <<locked>> | 82% | 57,188 psi | 90% | 2825 fps | 99.3% |
| Accurate 2460 | <<locked>> | 86% | 55,390 psi | 87% | 2749 fps | 100% |
| Accurate 2495 | <<locked>> | 94% | 54,041 psi | 85% | 2740 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 57,261 psi | 90% | 2812 fps | 100% |
| Accurate 4064 | <<locked>> | 98% | 57,290 psi | 90% | 2825 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 46,195 psi | 72% | 2730 fps | 97.5% |
| Accurate LT-30 | <<locked>> | 84% | 56,782 psi | 89% | 2674 fps | 100% |
| Accurate LT-32 | <<locked>> | 84% | 57,246 psi | 90% | 2700 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 56,101 psi | 88% | 2818 fps | 99.6% |
| ADI AR 2208 | <<locked>> | 98% | 57,058 psi | 89% | 2812 fps | 99.4% |
| ADI AR 2219 | <<locked>> | 82% | 54,056 psi | 85% | 2746 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 55,434 psi | 87% | 2776 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 90% | 55,230 psi | 87% | 2753 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 57,174 psi | 90% | 2881 fps | 99.9% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 55,825 psi | 87% | 2930 fps | 99.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 98% | 56,376 psi | 88% | 2831 fps | 99.9% |
| Alliant Reloder-10x | <<locked>> | 86% | 56,782 psi | 89% | 2733 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 57,203 psi | 90% | 2851 fps | 99.5% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 46,209 psi | 72% | 2740 fps | 97.6% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 53,447 psi | 84% | 2890 fps | 99.8% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 56,014 psi | 88% | 2674 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 56,144 psi | 88% | 2835 fps | 99.1% |
| Bofors RP3 | <<locked>> | 98% | 56,739 psi | 89% | 2844 fps | 100% |
| Hodgdon Benchmark | <<locked>> | 90% | 57,667 psi | 90% | 2762 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 90% | 54,172 psi | 85% | 2802 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 88% | 56,318 psi | 88% | 2897 fps | 99.5% |
| Hodgdon H322 | <<locked>> | 86% | 56,289 psi | 88% | 2776 fps | 100% |
| Hodgdon H335 | <<locked>> | 86% | 57,435 psi | 90% | 2802 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 54,665 psi | 86% | 2805 fps | 98.4% |
| Hodgdon H4895 | <<locked>> | 92% | 56,594 psi | 89% | 2828 fps | 99.8% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 42,105 psi | 66% | 2621 fps | 98.1% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 55,477 psi | 87% | 2858 fps | 99.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,519 psi | 54% | 1670 fps | 100% |
| Hodgdon VARGET | <<locked>> | 92% | 54,752 psi | 86% | 2782 fps | 99.7% |
| IMR 3031 | <<locked>> | 92% | 55,956 psi | 88% | 2815 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 56,666 psi | 89% | 2799 fps | 99.4% |
| IMR 4166 Enduron | <<locked>> | 94% | 57,537 psi | 90% | 2779 fps | 96.7% |
| IMR 4198 | <<locked>> | 86% | 57,363 psi | 90% | 2697 fps | 100% |
| IMR 4451 Enduronᴾ | <<locked>> | 100% | 56,391 psi | 88% | 2792 fps | 96.5% |
| IMR 4831ᴾ | <<locked>> | 100% | 44,092 psi | 69% | 2674 fps | 97.1% |
| IMR 4895 | <<locked>> | 94% | 54,998 psi | 86% | 2835 fps | 99.6% |
| IMR 8208 XBR | <<locked>> | 90% | 55,434 psi | 87% | 2776 fps | 99.9% |
| Lovex D073.5 | <<locked>> | 86% | 55,405 psi | 87% | 2762 fps | 100% |
| Lovex D073.6 | <<locked>> | 92% | 55,230 psi | 87% | 2795 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 56,347 psi | 88% | 2753 fps | 99.6% |
| Lovex S062 | <<locked>> | 96% | 55,738 psi | 87% | 2792 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 51,503 psi | 81% | 2730 fps | 97.1% |
| Norma 200 | <<locked>> | 82% | 56,536 psi | 89% | 2703 fps | 100% |
| Norma 201 | <<locked>> | 92% | 54,621 psi | 86% | 2762 fps | 99.9% |
| Norma 202 | <<locked>> | 92% | 55,201 psi | 87% | 2772 fps | 100% |
| Norma 203B | <<locked>> | 96% | 56,260 psi | 88% | 2841 fps | 99.7% |
| Norma URPᴾ | <<locked>> | 100% | 46,296 psi | 73% | 2726 fps | 97.3% |
| Ramshot Big Game | <<locked>> | 96% | 57,159 psi | 90% | 2871 fps | 99.7% |
| Ramshot TAC | <<locked>> | 90% | 56,130 psi | 88% | 2789 fps | 98% |
| Ramshot Wild Boar | <<locked>> | 90% | 55,274 psi | 87% | 2812 fps | 99.5% |
| Ramshot X-Terminator | <<locked>> | 88% | 56,898 psi | 89% | 2779 fps | 99.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,737 psi | 54% | 1709 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 55,114 psi | 86% | 2762 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 55,564 psi | 87% | 2789 fps | 97.1% |
| ReloadSwiss RS 52 | <<locked>> | 94% | 57,580 psi | 90% | 2923 fps | 99.5% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 57,159 psi | 90% | 2953 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 45,977 psi | 72% | 2746 fps | 97.1% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 47,195 psi | 74% | 2766 fps | 96.5% |
| Rottweil R 901 | <<locked>> | 90% | 55,521 psi | 87% | 2749 fps | 100% |
| Rottweil R 902 | <<locked>> | 94% | 54,940 psi | 86% | 2759 fps | 99.9% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 56,391 psi | 88% | 2835 fps | 99.9% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 51,503 psi | 81% | 2730 fps | 97.1% |
| Shooters World Match Rifle | <<locked>> | 92% | 55,230 psi | 87% | 2795 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 55,738 psi | 87% | 2792 fps | 100% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 55,143 psi | 86% | 2733 fps | 99.8% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 57,029 psi | 89% | 2431 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 54,389 psi | 85% | 2756 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 54,868 psi | 86% | 2844 fps | 99.5% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 54,694 psi | 86% | 2713 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 53,998 psi | 85% | 2762 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 54,476 psi | 85% | 2789 fps | 99.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 57,072 psi | 89% | 2713 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 56,782 psi | 89% | 2710 fps | 100% |
| Somchem S321 | <<locked>> | 88% | 56,855 psi | 89% | 2812 fps | 100% |
| Somchem S335 | <<locked>> | 92% | 55,869 psi | 88% | 2710 fps | 100% |
| Somchem S341 | <<locked>> | 92% | 57,421 psi | 90% | 2812 fps | 99.7% |
| Somchem S355ᴾ | <<locked>> | 100% | 56,913 psi | 89% | 2831 fps | 99.8% |
| Somchem S365ᴾ | <<locked>> | 100% | 41,002 psi | 64% | 2671 fps | 99.1% |
| Vihtavuori N130 | <<locked>> | 88% | 56,739 psi | 89% | 2680 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 57,043 psi | 89% | 2700 fps | 100% |
| Vihtavuori N135 | <<locked>> | 96% | 57,653 psi | 90% | 2772 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 55,695 psi | 87% | 2749 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 55,187 psi | 86% | 2766 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 48,936 psi | 77% | 2730 fps | 97.7% |
| Vihtavuori N530 | <<locked>> | 90% | 56,101 psi | 88% | 2779 fps | 100% |
| Vihtavuori N540 | <<locked>> | 96% | 57,363 psi | 90% | 2792 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 47,790 psi | 75% | 2730 fps | 97.4% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 50,024 psi | 78% | 2717 fps | 99.4% |
| Winchester 748 | <<locked>> | 90% | 55,405 psi | 87% | 2822 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 92% | 54,099 psi | 85% | 2795 fps | 99.7% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 41,568 psi | 65% | 2500 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 53,592 psi | 84% | 2772 fps | 98.9% |
| Accurate 2460 | <<locked>> | 80% | 45,121 psi | 71% | 2598 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 33,605 psi | 53% | 2402 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 40,379 psi | 63% | 2549 fps | 99.5% |
| Accurate 4064 | <<locked>> | 80% | 31,807 psi | 50% | 2382 fps | 98.7% |
| Accurate 4350 | <<locked>> | 96% | 39,885 psi | 63% | 2612 fps | 95.8% |
| Accurate LT-30 | <<locked>> | 80% | 50,256 psi | 79% | 2585 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 50,633 psi | 79% | 2608 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 38,189 psi | 60% | 2503 fps | 96.7% |
| ADI AR 2208 | <<locked>> | 84% | 37,057 psi | 58% | 2461 fps | 95.5% |
| ADI AR 2219 | <<locked>> | 80% | 50,415 psi | 79% | 2694 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 40,292 psi | 63% | 2520 fps | 98.3% |
| Alliant AR-Comp | <<locked>> | 80% | 39,349 psi | 62% | 2526 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 46,717 psi | 73% | 2713 fps | 99% |
| Alliant Power Pro 2000-MR | 72.3 gr | 84% | 39,581 psi | 62% | 2625 fps | 95.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 31,546 psi | 49% | 2372 fps | 95.4% |
| Alliant Reloder-10x | <<locked>> | 80% | 47,282 psi | 74% | 2602 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 36,361 psi | 57% | 2484 fps | 95.5% |
| Alliant Reloder-16 | <<locked>> | 94% | 38,247 psi | 60% | 2572 fps | 95.1% |
| Alliant Reloder-17 | <<locked>> | 86% | 33,330 psi | 52% | 2484 fps | 95.1% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 49,211 psi | 77% | 2582 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 37,159 psi | 58% | 2497 fps | 95% |
| Bofors RP3 | <<locked>> | 80% | 30,618 psi | 48% | 2362 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 42,322 psi | 66% | 2520 fps | 99.1% |
| Hodgdon BL-C2 | <<locked>> | 80% | 38,290 psi | 60% | 2530 fps | 98.5% |
| Hodgdon CFE223 | <<locked>> | 80% | 42,235 psi | 66% | 2661 fps | 97.2% |
| Hodgdon H322 | <<locked>> | 80% | 46,035 psi | 72% | 2628 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 46,731 psi | 73% | 2648 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 41,785 psi | 65% | 2585 fps | 95.7% |
| Hodgdon H4895 | <<locked>> | 80% | 38,464 psi | 60% | 2513 fps | 97.3% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 32,677 psi | 51% | 2415 fps | 95% |
| Hodgdon LEVERevolution | 67.5 gr | 80% | 34,461 psi | 54% | 2474 fps | 96.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,628 psi | 40% | 1493 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 37,130 psi | 58% | 2470 fps | 96.9% |
| IMR 3031 | <<locked>> | 80% | 37,449 psi | 59% | 2523 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 36,405 psi | 57% | 2441 fps | 95.6% |
| IMR 4166 Enduron | <<locked>> | 90% | 50,589 psi | 79% | 2671 fps | 95.3% |
| IMR 4198 | <<locked>> | 80% | 47,950 psi | 75% | 2566 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 96% | 49,777 psi | 78% | 2687 fps | 95% |
| IMR 4831 | <<locked>> | 96% | 38,580 psi | 60% | 2566 fps | 95.5% |
| IMR 4895 | <<locked>> | 80% | 34,853 psi | 55% | 2461 fps | 95.7% |
| IMR 8208 XBR | <<locked>> | 80% | 40,292 psi | 63% | 2520 fps | 98.3% |
| Lovex D073.5 | <<locked>> | 80% | 44,962 psi | 70% | 2605 fps | 99.6% |
| Lovex D073.6 | <<locked>> | 80% | 36,463 psi | 57% | 2480 fps | 98.9% |
| Lovex S060 | <<locked>> | 80% | 39,073 psi | 61% | 2454 fps | 96.9% |
| Lovex S062 | <<locked>> | 80% | 33,721 psi | 53% | 2395 fps | 96.7% |
| Lovex S065 | <<locked>> | 96% | 45,571 psi | 71% | 2628 fps | 95.7% |
| Norma 200 | <<locked>> | 80% | 53,026 psi | 83% | 2657 fps | 100% |
| Norma 201 | <<locked>> | 80% | 37,275 psi | 58% | 2461 fps | 97.7% |
| Norma 202 | <<locked>> | 80% | 37,565 psi | 59% | 2480 fps | 99.5% |
| Norma 203B | <<locked>> | 80% | 33,446 psi | 52% | 2418 fps | 95.1% |
| Norma URP | <<locked>> | 94% | 38,058 psi | 60% | 2562 fps | 95% |
| Ramshot Big Game | <<locked>> | 82% | 35,244 psi | 55% | 2480 fps | 95.4% |
| Ramshot TAC | <<locked>> | 82% | 42,989 psi | 67% | 2569 fps | 95.2% |
| Ramshot Wild Boar | <<locked>> | 80% | 39,247 psi | 62% | 2533 fps | 96.9% |
| Ramshot X-Terminator | <<locked>> | 80% | 43,758 psi | 69% | 2569 fps | 97.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,773 psi | 40% | 1526 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 45,368 psi | 71% | 2612 fps | 99.8% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 48,617 psi | 76% | 2680 fps | 95.6% |
| ReloadSwiss RS 52 | 68.4 gr | 82% | 37,782 psi | 59% | 2579 fps | 95.9% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 29,124 psi | 46% | 2379 fps | 95.8% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 39,987 psi | 63% | 2631 fps | 95.4% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 44,077 psi | 69% | 2707 fps | 95.5% |
| Rottweil R 901 | <<locked>> | 80% | 40,944 psi | 64% | 2513 fps | 99.7% |
| Rottweil R 902 | <<locked>> | 80% | 35,447 psi | 56% | 2415 fps | 97.2% |
| Rottweil R 903 | <<locked>> | 84% | 32,967 psi | 52% | 2415 fps | 95.8% |
| Shooters World Long Rifle | <<locked>> | 96% | 45,571 psi | 71% | 2628 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 36,463 psi | 57% | 2480 fps | 98.9% |
| Shooters World Precision | <<locked>> | 80% | 33,721 psi | 53% | 2395 fps | 96.7% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 47,921 psi | 75% | 2625 fps | 99.3% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 53,998 psi | 85% | 2395 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 50,676 psi | 79% | 2703 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 34,577 psi | 54% | 2470 fps | 95.2% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 48,080 psi | 75% | 2618 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 40,857 psi | 64% | 2539 fps | 95.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 36,782 psi | 58% | 2470 fps | 96.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 39,117 psi | 61% | 2434 fps | 99.6% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 32,068 psi | 50% | 2300 fps | 99.1% |
| Somchem S321 | <<locked>> | 80% | 43,178 psi | 68% | 2595 fps | 99.1% |
| Somchem S335 | <<locked>> | 80% | 38,522 psi | 60% | 2438 fps | 99.9% |
| Somchem S341 | <<locked>> | 80% | 37,811 psi | 59% | 2484 fps | 96.4% |
| Somchem S355 | <<locked>> | 82% | 32,024 psi | 50% | 2375 fps | 95.1% |
| Somchem S365 | <<locked>> | 90% | 29,689 psi | 47% | 2398 fps | 95.3% |
| Vihtavuori N130 | <<locked>> | 80% | 44,469 psi | 70% | 2510 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 39,320 psi | 62% | 2438 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 34,476 psi | 54% | 2411 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 35,418 psi | 56% | 2415 fps | 99.4% |
| Vihtavuori N150 | <<locked>> | 80% | 28,413 psi | 45% | 2267 fps | 95.2% |
| Vihtavuori N160 | <<locked>> | 94% | 40,030 psi | 63% | 2569 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 40,161 psi | 63% | 2513 fps | 98.4% |
| Vihtavuori N540 | <<locked>> | 80% | 33,997 psi | 53% | 2398 fps | 98.7% |
| Vihtavuori N550 | <<locked>> | 94% | 39,175 psi | 61% | 2569 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 33,446 psi | 52% | 2395 fps | 95.4% |
| Winchester 748 | <<locked>> | 80% | 39,160 psi | 61% | 2552 fps | 98.9% |
| Winchester StaBALL Match | <<locked>> | 80% | 35,911 psi | 56% | 2470 fps | 96.6% |
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 96 powders for .375 Weath. Mag. loaded with the .375 | 245gr | Reichenberg HDB Universal. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,953 fps; across all powders the maximum-charge window runs from 1,670 fps to 2,953 fps. Accurate 4350 gives the best case fill at 100 %, and 96 of the 96 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 54–90 %, leaving at least 10 % headroom. The 245.0 gr projectile in 0.375" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-17 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. Alliant Power Pro 2000-MR, ReloadSwiss RS 52, Hodgdon LEVERevolution rank at the top here: for .375 Weath. Mag. with the .375 | 245gr | Reichenberg HDB Universal 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.