Load Specifications
Load data in caliber .375 Blaser Mag. with .375 | 250gr | NorthFork Bonded Core bullet and 97 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 60 and Alliant Reloder-17.
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: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 84% | 53,301 psi | 88% | 2703 fps | 100% |
| Accurate 2460 | <<locked>> | 82% | 54,969 psi | 90% | 2776 fps | 100% |
| Accurate 2495 | <<locked>> | 90% | 54,926 psi | 90% | 2772 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 53,374 psi | 88% | 2789 fps | 100% |
| Accurate 2700 | <<locked>> | 90% | 54,592 psi | 90% | 2769 fps | 96.8% |
| Accurate 4064 | <<locked>> | 92% | 55,027 psi | 90% | 2818 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 54,491 psi | 89% | 2897 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 86% | 52,402 psi | 86% | 2802 fps | 99.8% |
| ADI AR 2208 | <<locked>> | 92% | 53,243 psi | 87% | 2799 fps | 99.6% |
| ADI Benchmark 8208 | <<locked>> | 86% | 54,853 psi | 90% | 2805 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 51,880 psi | 85% | 2733 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 51,517 psi | 85% | 2910 fps | 99.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 53,127 psi | 87% | 2822 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 90% | 53,795 psi | 88% | 2844 fps | 99.8% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 52,446 psi | 86% | 2900 fps | 99.6% |
| Alliant Reloder-17 | <<locked>> | 96% | 53,563 psi | 88% | 2940 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 37,405 psi | 61% | 2635 fps | 98.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 41,582 psi | 68% | 2785 fps | 97.3% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 51,924 psi | 85% | 2812 fps | 99.4% |
| Bofors RP3 | <<locked>> | 92% | 53,577 psi | 88% | 2838 fps | 100% |
| Bofors RP7 | <<locked>> | 96% | 53,998 psi | 89% | 2802 fps | 96.9% |
| Hodgdon Benchmark | <<locked>> | 84% | 53,316 psi | 88% | 2740 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 86% | 54,056 psi | 89% | 2835 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 52,069 psi | 85% | 2874 fps | 99.7% |
| Hodgdon H380 | <<locked>> | 92% | 54,737 psi | 90% | 2848 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 98% | 53,896 psi | 88% | 2894 fps | 97.7% |
| Hodgdon H4350 | <<locked>> | 96% | 54,781 psi | 90% | 2858 fps | 96.4% |
| Hodgdon H4895 | <<locked>> | 86% | 52,953 psi | 87% | 2812 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 48,747 psi | 80% | 2779 fps | 99.8% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 51,837 psi | 85% | 2841 fps | 100% |
| Hodgdon Superformance | <<locked>> | 98% | 54,853 psi | 90% | 2930 fps | 97.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,346 psi | 58% | 1716 fps | 100% |
| Hodgdon VARGET | <<locked>> | 88% | 54,114 psi | 89% | 2815 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 52,562 psi | 86% | 2795 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 52,707 psi | 87% | 2782 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 88% | 53,026 psi | 87% | 2762 fps | 97.3% |
| IMR 4350ᴾ | <<locked>> | 100% | 53,867 psi | 88% | 2825 fps | 97% |
| IMR 4451 Enduron | <<locked>> | 94% | 52,605 psi | 86% | 2785 fps | 97.2% |
| IMR 4831ᴾ | <<locked>> | 100% | 51,445 psi | 84% | 2835 fps | 99.3% |
| IMR 4895 | <<locked>> | 88% | 51,692 psi | 85% | 2822 fps | 99.8% |
| IMR 8208 XBR | <<locked>> | 86% | 54,853 psi | 90% | 2805 fps | 100% |
| Lovex D073.5 | <<locked>> | 82% | 54,969 psi | 90% | 2789 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 51,880 psi | 85% | 2779 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 52,170 psi | 86% | 2730 fps | 99.8% |
| Lovex S062 | <<locked>> | 90% | 52,533 psi | 86% | 2779 fps | 100% |
| Lovex S065 | <<locked>> | 98% | 55,013 psi | 90% | 2828 fps | 98.8% |
| Lovex S070 | <<locked>> | 98% | 52,417 psi | 86% | 2808 fps | 97.5% |
| Norma 201 | <<locked>> | 88% | 54,389 psi | 89% | 2795 fps | 100% |
| Norma 202 | <<locked>> | 88% | 55,013 psi | 90% | 2799 fps | 100% |
| Norma 203B | <<locked>> | 90% | 52,968 psi | 87% | 2831 fps | 99.9% |
| Norma URPᴾ | <<locked>> | 100% | 53,664 psi | 88% | 2887 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 90% | 53,316 psi | 88% | 2854 fps | 99.9% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 52,518 psi | 86% | 2881 fps | 98.2% |
| Ramshot TAC | <<locked>> | 84% | 51,706 psi | 85% | 2769 fps | 98.4% |
| Ramshot Wild Boar | <<locked>> | 86% | 54,578 psi | 90% | 2838 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 82% | 52,286 psi | 86% | 2753 fps | 99.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,839 psi | 59% | 1759 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 82% | 54,331 psi | 89% | 2785 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 54,940 psi | 90% | 2828 fps | 98.2% |
| ReloadSwiss RS 52 | <<locked>> | 88% | 53,911 psi | 89% | 2907 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 53,447 psi | 88% | 2943 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 54,056 psi | 89% | 2920 fps | 99.4% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 54,099 psi | 89% | 2946 fps | 99.2% |
| Rottweil R 901 | <<locked>> | 84% | 52,243 psi | 86% | 2733 fps | 100% |
| Rottweil R 902 | <<locked>> | 90% | 54,868 psi | 90% | 2792 fps | 100% |
| Rottweil R 903 | <<locked>> | 94% | 53,447 psi | 88% | 2828 fps | 100% |
| Rottweil R 907 | <<locked>> | 96% | 53,998 psi | 89% | 2802 fps | 96.9% |
| Shooters World Long Rifle | <<locked>> | 98% | 55,013 psi | 90% | 2828 fps | 98.8% |
| Shooters World Match Rifle | <<locked>> | 86% | 51,880 psi | 85% | 2779 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 52,533 psi | 86% | 2779 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 52,417 psi | 86% | 2808 fps | 97.5% |
| SNPE Vectan SP 11 | <<locked>> | 94% | 55,071 psi | 90% | 2887 fps | 99.9% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 53,330 psi | 88% | 2795 fps | 99% |
| SNPE Vectan SP 9 | <<locked>> | 88% | 54,041 psi | 89% | 2822 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 52,866 psi | 87% | 2690 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 52,736 psi | 87% | 2687 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 52,025 psi | 85% | 2730 fps | 97.1% |
| Somchem S321 | <<locked>> | 82% | 52,402 psi | 86% | 2782 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 52,127 psi | 86% | 2690 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 53,011 psi | 87% | 2792 fps | 99.8% |
| Somchem S355 | <<locked>> | 94% | 53,867 psi | 88% | 2825 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 47,921 psi | 79% | 2835 fps | 100% |
| Vihtavuori N130 | <<locked>> | 82% | 52,736 psi | 87% | 2657 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 53,069 psi | 87% | 2680 fps | 100% |
| Vihtavuori N135 | <<locked>> | 90% | 54,520 psi | 90% | 2759 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 52,156 psi | 86% | 2733 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 51,895 psi | 85% | 2756 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 52,779 psi | 87% | 2831 fps | 99.3% |
| Vihtavuori N530 | <<locked>> | 84% | 51,808 psi | 85% | 2753 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 53,650 psi | 88% | 2776 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 51,721 psi | 85% | 2835 fps | 99.1% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 40,553 psi | 67% | 2710 fps | 98.1% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 53,214 psi | 87% | 2812 fps | 100% |
| Winchester 748 | <<locked>> | 86% | 55,100 psi | 90% | 2851 fps | 100% |
| Winchester 760 | <<locked>> | 98% | 54,070 psi | 89% | 2897 fps | 97.7% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 33,460 psi | 55% | 2625 fps | 97.7% |
| Winchester StaBALL Match | <<locked>> | 88% | 53,867 psi | 88% | 2831 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 47,166 psi | 77% | 2615 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 51,503 psi | 85% | 2726 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 39,784 psi | 65% | 2543 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 46,543 psi | 76% | 2687 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 47,848 psi | 79% | 2661 fps | 95.3% |
| Accurate 4064 | <<locked>> | 80% | 37,579 psi | 62% | 2533 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 33,605 psi | 55% | 2510 fps | 95.2% |
| ADI AR 2206H | <<locked>> | 80% | 43,337 psi | 71% | 2644 fps | 98.9% |
| ADI AR 2208 | <<locked>> | 80% | 36,941 psi | 61% | 2497 fps | 96.9% |
| ADI Benchmark 8208 | <<locked>> | 80% | 45,382 psi | 75% | 2654 fps | 99.8% |
| Alliant AR-Comp | <<locked>> | 80% | 45,426 psi | 75% | 2641 fps | 100% |
| Alliant Power Pro 2000-MR | 74.6 gr | 80% | 39,291 psi | 65% | 2671 fps | 97.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 36,448 psi | 60% | 2520 fps | 98.3% |
| Alliant Reloder-15 | <<locked>> | 80% | 39,088 psi | 64% | 2579 fps | 97.7% |
| Alliant Reloder-16 | <<locked>> | 86% | 34,127 psi | 56% | 2523 fps | 95.3% |
| Alliant Reloder-17 | 73.4 gr | 80% | 31,343 psi | 51% | 2477 fps | 96.1% |
| Alliant Reloder-23 | <<locked>> | 94% | 31,198 psi | 51% | 2477 fps | 95.8% |
| Alliant Reloder-26 | <<locked>> | 96% | 36,143 psi | 59% | 2657 fps | 95.2% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 42,395 psi | 70% | 2644 fps | 97.9% |
| Bofors RP3 | <<locked>> | 80% | 35,955 psi | 59% | 2523 fps | 98.3% |
| Bofors RP7 | <<locked>> | 92% | 47,587 psi | 78% | 2697 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 47,108 psi | 77% | 2641 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 44,135 psi | 72% | 2674 fps | 99.9% |
| Hodgdon CFE223 | <<locked>> | 80% | 48,559 psi | 80% | 2815 fps | 99.4% |
| Hodgdon H380 | <<locked>> | 80% | 36,782 psi | 60% | 2520 fps | 95.7% |
| Hodgdon H414 | <<locked>> | 92% | 44,193 psi | 73% | 2726 fps | 95.5% |
| Hodgdon H4350 | <<locked>> | 92% | 48,327 psi | 79% | 2749 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 43,700 psi | 72% | 2654 fps | 99.3% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 29,327 psi | 48% | 2369 fps | 95.3% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 39,595 psi | 65% | 2625 fps | 99% |
| Hodgdon Superformance | <<locked>> | 94% | 47,500 psi | 78% | 2805 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,310 psi | 43% | 1532 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 42,003 psi | 69% | 2608 fps | 99% |
| IMR 3031 | <<locked>> | 80% | 43,366 psi | 71% | 2654 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 38,769 psi | 64% | 2530 fps | 97.6% |
| IMR 4166 Enduron | <<locked>> | 82% | 43,947 psi | 72% | 2602 fps | 95.2% |
| IMR 4350 | <<locked>> | 96% | 47,703 psi | 78% | 2723 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 88% | 43,772 psi | 72% | 2628 fps | 95.1% |
| IMR 4831 | <<locked>> | 88% | 34,824 psi | 57% | 2520 fps | 95.7% |
| IMR 4895 | <<locked>> | 80% | 40,016 psi | 66% | 2608 fps | 98.4% |
| IMR 8208 XBR | <<locked>> | 80% | 45,382 psi | 75% | 2654 fps | 99.8% |
| Lovex D073.5 | <<locked>> | 80% | 51,329 psi | 84% | 2736 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 42,279 psi | 69% | 2625 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 43,511 psi | 71% | 2582 fps | 99% |
| Lovex S062 | <<locked>> | 80% | 38,595 psi | 63% | 2536 fps | 99% |
| Lovex S065 | <<locked>> | 86% | 38,130 psi | 63% | 2523 fps | 95.1% |
| Lovex S070 | <<locked>> | 92% | 43,468 psi | 71% | 2651 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 42,511 psi | 70% | 2598 fps | 99.5% |
| Norma 202 | <<locked>> | 80% | 42,757 psi | 70% | 2608 fps | 100% |
| Norma 203B | <<locked>> | 80% | 38,450 psi | 63% | 2569 fps | 98% |
| Norma URP | <<locked>> | 86% | 33,997 psi | 56% | 2510 fps | 95.1% |
| Ramshot Big Game | <<locked>> | 80% | 37,971 psi | 62% | 2579 fps | 97.7% |
| Ramshot Hunter | <<locked>> | 92% | 40,451 psi | 66% | 2657 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 45,324 psi | 74% | 2657 fps | 97.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 44,686 psi | 73% | 2677 fps | 99.1% |
| Ramshot X-Terminator | <<locked>> | 80% | 48,921 psi | 80% | 2700 fps | 99.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,556 psi | 44% | 1568 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 50,908 psi | 84% | 2733 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 42,540 psi | 70% | 2615 fps | 95.6% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 40,886 psi | 67% | 2677 fps | 98.1% |
| ReloadSwiss RS 60 | 73.4 gr | 80% | 33,373 psi | 55% | 2546 fps | 99.1% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 35,781 psi | 59% | 2579 fps | 95.6% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 38,580 psi | 63% | 2644 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 46,412 psi | 76% | 2641 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 40,451 psi | 66% | 2552 fps | 99.3% |
| Rottweil R 903 | <<locked>> | 80% | 33,750 psi | 55% | 2464 fps | 97.4% |
| Rottweil R 907 | <<locked>> | 92% | 47,587 psi | 78% | 2697 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 86% | 38,130 psi | 63% | 2523 fps | 95.1% |
| Shooters World Match Rifle | <<locked>> | 80% | 42,279 psi | 69% | 2625 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 38,595 psi | 63% | 2536 fps | 99% |
| Shooters World SW4350 | <<locked>> | 92% | 43,468 psi | 71% | 2651 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 34,780 psi | 57% | 2513 fps | 96.9% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 43,497 psi | 71% | 2631 fps | 97.4% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 41,872 psi | 69% | 2615 fps | 98.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 43,888 psi | 72% | 2552 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 36,405 psi | 60% | 2421 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 42,670 psi | 70% | 2572 fps | 95% |
| Somchem S321 | <<locked>> | 80% | 48,979 psi | 80% | 2730 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 43,526 psi | 71% | 2556 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 43,163 psi | 71% | 2628 fps | 98.8% |
| Somchem S355 | <<locked>> | 80% | 34,751 psi | 57% | 2474 fps | 97.5% |
| Somchem S365 | <<locked>> | 82% | 26,832 psi | 44% | 2352 fps | 95.6% |
| Vihtavuori N130 | <<locked>> | 80% | 49,559 psi | 81% | 2612 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 44,150 psi | 72% | 2549 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 39,798 psi | 65% | 2536 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 40,364 psi | 66% | 2543 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 32,938 psi | 54% | 2408 fps | 98.2% |
| Vihtavuori N160 | <<locked>> | 86% | 35,679 psi | 59% | 2516 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 80% | 45,484 psi | 75% | 2651 fps | 99.8% |
| Vihtavuori N540 | <<locked>> | 80% | 38,899 psi | 64% | 2533 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 86% | 35,012 psi | 57% | 2516 fps | 95.3% |
| Vihtavuori N555 | <<locked>> | 92% | 31,241 psi | 51% | 2497 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 29,327 psi | 48% | 2333 fps | 95.3% |
| Winchester 748 | <<locked>> | 80% | 45,005 psi | 74% | 2694 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 44,338 psi | 73% | 2730 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 96% | 29,486 psi | 48% | 2493 fps | 95.2% |
| Winchester StaBALL Match | <<locked>> | 80% | 41,205 psi | 68% | 2618 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 97 powders for .375 Blaser Mag. loaded with the .375 | 250gr | NorthFork Bonded Core. ReloadSwiss RS 70 delivers the highest muzzle velocity at 2,946 fps; across all powders the maximum-charge window runs from 1,716 fps to 2,946 fps. Accurate 4350 gives the best case fill at 100 %, and 97 of the 97 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (420 MPa), the top charges use 55–90 %, 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 4350, Alliant Reloder-16, Alliant Reloder-23 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 60, Alliant Reloder-17 rank at the top here: for .375 Blaser Mag. with the .375 | 250gr | NorthFork Bonded Core 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.