Load Specifications
Load data in caliber .375 Blaser Mag. with .375 | 270gr | Barnes Banded Solid RN bullet and 98 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-17, ReloadSwiss RS 60 and Winchester 760.
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: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 82% | 52,359 psi | 86% | 2582 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 54,114 psi | 89% | 2648 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 52,373 psi | 86% | 2667 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 53,330 psi | 88% | 2651 fps | 97.3% |
| Accurate 3100ᴾ | <<locked>> | 100% | 41,089 psi | 67% | 2556 fps | 96.6% |
| Accurate 4064 | <<locked>> | 90% | 54,186 psi | 89% | 2697 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 53,809 psi | 88% | 2782 fps | 99.8% |
| ADI AR 2206H | <<locked>> | 86% | 54,650 psi | 90% | 2730 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 52,243 psi | 86% | 2677 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 84% | 53,548 psi | 88% | 2677 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 54,549 psi | 90% | 2651 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 54,027 psi | 89% | 2841 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 52,156 psi | 86% | 2700 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 52,808 psi | 87% | 2720 fps | 99.9% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 55,056 psi | 90% | 2835 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 94% | 52,634 psi | 86% | 2818 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 39,479 psi | 65% | 2589 fps | 99.3% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 43,947 psi | 72% | 2743 fps | 98.7% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 54,273 psi | 89% | 2743 fps | 99.8% |
| Bofors RP3 | <<locked>> | 90% | 52,750 psi | 87% | 2717 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 52,968 psi | 87% | 2687 fps | 97.5% |
| Hodgdon Benchmark | <<locked>> | 82% | 52,011 psi | 85% | 2612 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 52,939 psi | 87% | 2710 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 54,824 psi | 90% | 2802 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 53,635 psi | 88% | 2730 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 96% | 53,026 psi | 87% | 2779 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 94% | 53,824 psi | 88% | 2740 fps | 97.1% |
| Hodgdon H4895 | <<locked>> | 84% | 51,750 psi | 85% | 2687 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 51,242 psi | 84% | 2713 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 54,607 psi | 90% | 2769 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 53,606 psi | 88% | 2812 fps | 97.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,534 psi | 58% | 1647 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 52,910 psi | 87% | 2690 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 51,750 psi | 85% | 2671 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 55,013 psi | 90% | 2710 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 54,998 psi | 90% | 2690 fps | 98.3% |
| IMR 4350 | <<locked>> | 98% | 52,953 psi | 87% | 2710 fps | 97.6% |
| IMR 4451 Enduron | <<locked>> | 94% | 54,781 psi | 90% | 2717 fps | 98.2% |
| IMR 4831ᴾ | <<locked>> | 100% | 54,389 psi | 89% | 2772 fps | 99.8% |
| IMR 4895 | <<locked>> | 88% | 54,128 psi | 89% | 2749 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 53,548 psi | 88% | 2677 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 54,288 psi | 89% | 2700 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 54,273 psi | 89% | 2657 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 54,926 psi | 90% | 2707 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 54,114 psi | 89% | 2713 fps | 99.1% |
| Lovex S070 | <<locked>> | 98% | 54,998 psi | 90% | 2746 fps | 98.5% |
| Norma 201 | <<locked>> | 86% | 53,490 psi | 88% | 2674 fps | 100% |
| Norma 202 | <<locked>> | 86% | 53,954 psi | 89% | 2674 fps | 100% |
| Norma 203B | <<locked>> | 88% | 52,054 psi | 85% | 2710 fps | 100% |
| Norma 204 | <<locked>> | 98% | 53,606 psi | 88% | 2759 fps | 96.4% |
| Norma MRPᴾ | <<locked>> | 100% | 44,019 psi | 72% | 2700 fps | 96.1% |
| Norma URP | <<locked>> | 98% | 52,910 psi | 87% | 2769 fps | 99.7% |
| Ramshot Big Game | <<locked>> | 88% | 52,257 psi | 86% | 2730 fps | 100% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 55,071 psi | 90% | 2815 fps | 99.1% |
| Ramshot TAC | <<locked>> | 84% | 53,737 psi | 88% | 2697 fps | 99.2% |
| Ramshot Wild Boar | <<locked>> | 84% | 53,359 psi | 88% | 2713 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 54,433 psi | 89% | 2680 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,100 psi | 59% | 1686 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 53,867 psi | 88% | 2710 fps | 98.7% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 53,084 psi | 87% | 2782 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 52,417 psi | 86% | 2815 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 53,330 psi | 88% | 2802 fps | 99.7% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 53,026 psi | 87% | 2828 fps | 99.6% |
| Rottweil R 901 | <<locked>> | 84% | 54,418 psi | 89% | 2651 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 53,940 psi | 89% | 2674 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 52,634 psi | 86% | 2707 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 52,968 psi | 87% | 2687 fps | 97.5% |
| Shooters World Long Rifle | <<locked>> | 96% | 54,114 psi | 89% | 2713 fps | 99.1% |
| Shooters World Match Rifle | <<locked>> | 86% | 54,288 psi | 89% | 2700 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 54,926 psi | 90% | 2707 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 54,998 psi | 90% | 2746 fps | 98.5% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 54,157 psi | 89% | 2766 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 52,185 psi | 86% | 2677 fps | 99.3% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 53,011 psi | 87% | 2700 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 54,824 psi | 90% | 2612 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 54,984 psi | 90% | 2612 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 54,447 psi | 89% | 2667 fps | 98.2% |
| Somchem S321 | <<locked>> | 82% | 54,694 psi | 90% | 2710 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 54,346 psi | 89% | 2612 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 51,735 psi | 85% | 2667 fps | 99.9% |
| Somchem S355 | <<locked>> | 92% | 52,939 psi | 87% | 2703 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 50,821 psi | 83% | 2772 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 47,311 psi | 78% | 2657 fps | 96.4% |
| Vihtavuori N130 | <<locked>> | 82% | 54,694 psi | 90% | 2572 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 55,071 psi | 90% | 2595 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 53,737 psi | 88% | 2638 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 54,491 psi | 89% | 2654 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 54,375 psi | 89% | 2684 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 51,996 psi | 85% | 2713 fps | 99.6% |
| Vihtavuori N530 | <<locked>> | 84% | 53,983 psi | 89% | 2677 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 52,475 psi | 86% | 2651 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 54,331 psi | 89% | 2769 fps | 99.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 43,120 psi | 71% | 2657 fps | 99.2% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 52,098 psi | 86% | 2694 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 53,911 psi | 89% | 2723 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 53,200 psi | 87% | 2779 fps | 98.2% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 35,201 psi | 58% | 2595 fps | 99.3% |
| Winchester StaBALL Match | <<locked>> | 86% | 52,779 psi | 87% | 2707 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% | 49,153 psi | 81% | 2536 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 41,843 psi | 69% | 2470 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 48,805 psi | 80% | 2615 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 43,874 psi | 72% | 2497 fps | 95.2% |
| Accurate 3100 | <<locked>> | 96% | 35,882 psi | 59% | 2454 fps | 95% |
| Accurate 4064 | <<locked>> | 80% | 39,595 psi | 65% | 2470 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 30,995 psi | 51% | 2352 fps | 95.1% |
| ADI AR 2206H | <<locked>> | 80% | 45,252 psi | 74% | 2579 fps | 99.6% |
| ADI AR 2208 | <<locked>> | 80% | 38,522 psi | 63% | 2438 fps | 98% |
| ADI Benchmark 8208 | <<locked>> | 80% | 47,340 psi | 78% | 2582 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 47,877 psi | 79% | 2566 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 41,162 psi | 68% | 2615 fps | 98.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,218 psi | 63% | 2461 fps | 99.2% |
| Alliant Reloder-15 | <<locked>> | 80% | 40,973 psi | 67% | 2520 fps | 98.7% |
| Alliant Reloder-16 | <<locked>> | 82% | 31,633 psi | 52% | 2369 fps | 95.3% |
| Alliant Reloder-17 | 72.3 gr | 80% | 32,953 psi | 54% | 2434 fps | 97.7% |
| Alliant Reloder-23 | <<locked>> | 90% | 29,008 psi | 48% | 2329 fps | 95.9% |
| Alliant Reloder-26 | <<locked>> | 92% | 33,315 psi | 55% | 2500 fps | 95.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 44,382 psi | 73% | 2582 fps | 98.9% |
| Bofors RP3 | <<locked>> | 80% | 37,768 psi | 62% | 2461 fps | 99.2% |
| Bofors RP7 | <<locked>> | 88% | 43,947 psi | 72% | 2536 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 80% | 49,124 psi | 81% | 2569 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 46,209 psi | 76% | 2605 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 51,082 psi | 84% | 2746 fps | 99.8% |
| Hodgdon H380 | <<locked>> | 80% | 38,667 psi | 63% | 2467 fps | 97.1% |
| Hodgdon H414 | <<locked>> | 88% | 40,828 psi | 67% | 2562 fps | 95.4% |
| Hodgdon H4350 | <<locked>> | 90% | 47,572 psi | 78% | 2638 fps | 95.7% |
| Hodgdon H4895 | <<locked>> | 80% | 45,672 psi | 75% | 2589 fps | 99.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 27,253 psi | 45% | 2224 fps | 95.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 41,742 psi | 69% | 2566 fps | 99.7% |
| Hodgdon Superformance | <<locked>> | 90% | 43,236 psi | 71% | 2631 fps | 95.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,484 psi | 43% | 1470 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 43,845 psi | 72% | 2543 fps | 99.6% |
| IMR 3031 | <<locked>> | 80% | 45,498 psi | 75% | 2579 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 40,451 psi | 66% | 2467 fps | 98.6% |
| IMR 4166 Enduron | <<locked>> | 80% | 42,946 psi | 71% | 2490 fps | 95.9% |
| IMR 4350 | <<locked>> | 92% | 44,048 psi | 72% | 2562 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 84% | 40,422 psi | 66% | 2470 fps | 95% |
| IMR 4831 | <<locked>> | 84% | 32,314 psi | 53% | 2369 fps | 95.7% |
| IMR 4895 | <<locked>> | 80% | 41,959 psi | 69% | 2546 fps | 99.3% |
| IMR 8208 XBR | <<locked>> | 80% | 47,340 psi | 78% | 2582 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 44,512 psi | 73% | 2556 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 45,179 psi | 74% | 2513 fps | 99.6% |
| Lovex S062 | <<locked>> | 80% | 40,335 psi | 66% | 2470 fps | 99.7% |
| Lovex S065 | <<locked>> | 82% | 35,317 psi | 58% | 2369 fps | 95% |
| Lovex S070 | <<locked>> | 88% | 40,350 psi | 66% | 2497 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 44,338 psi | 73% | 2530 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 44,686 psi | 73% | 2536 fps | 100% |
| Norma 203B | <<locked>> | 80% | 40,335 psi | 66% | 2507 fps | 99% |
| Norma 204 | <<locked>> | 96% | 50,111 psi | 82% | 2703 fps | 95.7% |
| Norma MRP | <<locked>> | 98% | 41,176 psi | 68% | 2644 fps | 95.2% |
| Norma URP | <<locked>> | 82% | 31,575 psi | 52% | 2359 fps | 95.1% |
| Ramshot Big Game | <<locked>> | 80% | 39,871 psi | 65% | 2520 fps | 98.8% |
| Ramshot Hunter | <<locked>> | 88% | 37,449 psi | 61% | 2500 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 47,224 psi | 78% | 2595 fps | 98.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 46,760 psi | 77% | 2612 fps | 99.7% |
| Ramshot X-Terminator | <<locked>> | 80% | 50,923 psi | 84% | 2628 fps | 99.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,919 psi | 44% | 1506 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 39,073 psi | 64% | 2451 fps | 95.5% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 43,076 psi | 71% | 2618 fps | 99.1% |
| ReloadSwiss RS 60 | 72.3 gr | 80% | 35,070 psi | 58% | 2497 fps | 99.8% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 32,982 psi | 54% | 2421 fps | 95.5% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 35,462 psi | 58% | 2484 fps | 95.5% |
| Rottweil R 901 | <<locked>> | 80% | 48,457 psi | 80% | 2566 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,192 psi | 69% | 2487 fps | 99.8% |
| Rottweil R 903 | <<locked>> | 80% | 35,694 psi | 59% | 2411 fps | 98.6% |
| Rottweil R 907 | <<locked>> | 88% | 43,947 psi | 72% | 2536 fps | 95.5% |
| Shooters World Long Rifle | <<locked>> | 82% | 35,317 psi | 58% | 2369 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 44,512 psi | 73% | 2556 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 40,335 psi | 66% | 2470 fps | 99.7% |
| Shooters World SW4350 | <<locked>> | 88% | 40,350 psi | 66% | 2497 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 36,463 psi | 60% | 2457 fps | 98.1% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 45,513 psi | 75% | 2569 fps | 98.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 43,671 psi | 72% | 2549 fps | 99.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 45,745 psi | 75% | 2480 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,101 psi | 63% | 2359 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 42,003 psi | 69% | 2467 fps | 95.7% |
| Somchem S321 | <<locked>> | 80% | 51,126 psi | 84% | 2657 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 45,295 psi | 74% | 2484 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 45,165 psi | 74% | 2562 fps | 99.5% |
| Somchem S355 | <<locked>> | 80% | 36,434 psi | 60% | 2415 fps | 98.6% |
| Somchem S365 | <<locked>> | 80% | 26,455 psi | 43% | 2260 fps | 96.5% |
| Somchem S385 | <<locked>> | 98% | 44,193 psi | 73% | 2605 fps | 95.6% |
| Vihtavuori N130 | <<locked>> | 80% | 51,590 psi | 85% | 2533 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 46,093 psi | 76% | 2474 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 41,872 psi | 69% | 2467 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 42,380 psi | 70% | 2477 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 34,708 psi | 57% | 2356 fps | 99.2% |
| Vihtavuori N160 | <<locked>> | 82% | 32,880 psi | 54% | 2359 fps | 95.6% |
| Vihtavuori N530 | <<locked>> | 80% | 47,355 psi | 78% | 2579 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 40,741 psi | 67% | 2467 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 32,430 psi | 53% | 2362 fps | 95.2% |
| Vihtavuori N555 | <<locked>> | 88% | 29,196 psi | 48% | 2352 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 30,647 psi | 50% | 2283 fps | 97% |
| Winchester 748 | <<locked>> | 80% | 47,137 psi | 77% | 2625 fps | 100% |
| Winchester 760 | 77.8 gr | 88% | 40,828 psi | 67% | 2562 fps | 95.4% |
| Winchester StaBALL HD | <<locked>> | 92% | 27,296 psi | 45% | 2346 fps | 95.2% |
| Winchester StaBALL Match | <<locked>> | 80% | 43,163 psi | 71% | 2552 fps | 99.6% |
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 98 powders for .375 Blaser Mag. loaded with the .375 | 270gr | Barnes Banded Solid RN. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,841 fps; across all powders the maximum-charge window runs from 1,647 fps to 2,841 fps. Accurate 3100 gives the best case fill at 100 %, and 98 of the 98 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (420 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 270.0 gr projectile in 0.375" calls for a 1:6.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, 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 Reloder-17, ReloadSwiss RS 60, Winchester 760 rank at the top here: for .375 Blaser Mag. with the .375 | 270gr | Barnes Banded Solid RN 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.