Load Specifications
Load data in caliber .375 Blaser Mag. with .375 | 270gr | Barnes Banded Solid RN LG bullet and 99 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, Hodgdon Superformance and ReloadSwiss RS 60.
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>> | 84% | 54,752 psi | 90% | 2605 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 53,171 psi | 87% | 2631 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 53,200 psi | 87% | 2680 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 53,200 psi | 87% | 2680 fps | 100% |
| Accurate 2700 | <<locked>> | 92% | 53,461 psi | 88% | 2638 fps | 97.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 40,132 psi | 66% | 2533 fps | 96.2% |
| Accurate 4064 | <<locked>> | 90% | 53,229 psi | 87% | 2677 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 52,620 psi | 86% | 2759 fps | 99.7% |
| ADI AR 2206H | <<locked>> | 86% | 53,606 psi | 88% | 2703 fps | 100% |
| ADI AR 2208 | <<locked>> | 92% | 54,578 psi | 90% | 2707 fps | 99.9% |
| ADI Benchmark 8208 | <<locked>> | 84% | 52,692 psi | 87% | 2657 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 53,432 psi | 88% | 2631 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 53,142 psi | 87% | 2818 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 54,476 psi | 89% | 2726 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 51,764 psi | 85% | 2700 fps | 99.8% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 54,012 psi | 89% | 2808 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 94% | 51,590 psi | 85% | 2795 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 38,537 psi | 63% | 2562 fps | 99% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 42,888 psi | 70% | 2713 fps | 98.3% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 53,388 psi | 88% | 2723 fps | 99.8% |
| Bofors RP3 | <<locked>> | 90% | 51,735 psi | 85% | 2697 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 51,924 psi | 85% | 2664 fps | 97.2% |
| Hodgdon Benchmark | <<locked>> | 84% | 54,578 psi | 90% | 2641 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 51,953 psi | 85% | 2687 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 53,708 psi | 88% | 2782 fps | 99.9% |
| Hodgdon H322 | <<locked>> | 82% | 52,692 psi | 87% | 2641 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 52,678 psi | 86% | 2707 fps | 99.4% |
| Hodgdon H414 | <<locked>> | 94% | 53,563 psi | 88% | 2776 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 98% | 54,360 psi | 89% | 2740 fps | 97% |
| Hodgdon H4895 | <<locked>> | 86% | 54,157 psi | 89% | 2717 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 50,140 psi | 82% | 2690 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 90% | 53,534 psi | 88% | 2749 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 52,431 psi | 86% | 2785 fps | 97.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,491 psi | 58% | 1637 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 54,215 psi | 89% | 2700 fps | 100% |
| IMR 3031 | <<locked>> | 88% | 52,736 psi | 87% | 2677 fps | 100% |
| IMR 4064 | <<locked>> | 92% | 53,403 psi | 88% | 2677 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 92% | 52,924 psi | 87% | 2651 fps | 97.9% |
| IMR 4350 | <<locked>> | 98% | 51,996 psi | 85% | 2687 fps | 97.3% |
| IMR 4451 Enduron | <<locked>> | 94% | 53,911 psi | 89% | 2697 fps | 98% |
| IMR 4831ᴾ | <<locked>> | 100% | 47,326 psi | 78% | 2661 fps | 99.2% |
| IMR 4895 | <<locked>> | 88% | 53,069 psi | 87% | 2726 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 52,692 psi | 87% | 2657 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 53,403 psi | 88% | 2684 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 53,461 psi | 88% | 2638 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 54,099 psi | 89% | 2687 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 53,084 psi | 87% | 2687 fps | 98.9% |
| Lovex S070 | <<locked>> | 98% | 53,969 psi | 89% | 2723 fps | 98.3% |
| Norma 201 | <<locked>> | 86% | 52,620 psi | 86% | 2654 fps | 100% |
| Norma 202 | <<locked>> | 86% | 53,069 psi | 87% | 2657 fps | 100% |
| Norma 203B | <<locked>> | 90% | 54,360 psi | 89% | 2736 fps | 100% |
| Norma 204 | <<locked>> | 98% | 52,504 psi | 86% | 2733 fps | 96% |
| Norma URP | <<locked>> | 98% | 51,808 psi | 85% | 2746 fps | 99.6% |
| Ramshot Big Game | <<locked>> | 90% | 54,911 psi | 90% | 2762 fps | 100% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 53,940 psi | 89% | 2792 fps | 98.9% |
| Ramshot TAC | <<locked>> | 84% | 52,866 psi | 87% | 2677 fps | 99% |
| Ramshot Wild Boar | <<locked>> | 84% | 52,460 psi | 86% | 2694 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 53,490 psi | 88% | 2661 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,042 psi | 59% | 1680 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 53,055 psi | 87% | 2690 fps | 98.4% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 51,938 psi | 85% | 2759 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 55,013 psi | 90% | 2844 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 52,228 psi | 86% | 2779 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 51,996 psi | 85% | 2802 fps | 99.4% |
| Rottweil R 901 | <<locked>> | 84% | 53,650 psi | 88% | 2635 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 53,084 psi | 87% | 2654 fps | 100% |
| Rottweil R 903 | <<locked>> | 94% | 54,926 psi | 90% | 2733 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 51,924 psi | 85% | 2664 fps | 97.2% |
| Shooters World Long Rifle | <<locked>> | 96% | 53,084 psi | 87% | 2687 fps | 98.9% |
| Shooters World Match Rifle | <<locked>> | 86% | 53,403 psi | 88% | 2684 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 54,099 psi | 89% | 2687 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 53,969 psi | 89% | 2723 fps | 98.3% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 53,258 psi | 87% | 2746 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 54,781 psi | 90% | 2707 fps | 99.5% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 52,069 psi | 85% | 2677 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 54,099 psi | 89% | 2595 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 54,186 psi | 89% | 2592 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 53,476 psi | 88% | 2644 fps | 97.9% |
| Somchem S321 | <<locked>> | 82% | 53,737 psi | 88% | 2687 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 53,519 psi | 88% | 2595 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 54,491 psi | 89% | 2700 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 51,938 psi | 85% | 2684 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 49,574 psi | 81% | 2746 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 46,238 psi | 76% | 2631 fps | 96% |
| Unknown powder | <<locked>> | 96% | 52,895 psi | 87% | 2753 fps | 99.3% |
| Vihtavuori N130 | <<locked>> | 82% | 53,896 psi | 88% | 2559 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 54,331 psi | 89% | 2579 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 52,736 psi | 87% | 2618 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 53,447 psi | 88% | 2635 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 53,243 psi | 87% | 2661 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 54,302 psi | 89% | 2743 fps | 99.7% |
| Vihtavuori N530 | <<locked>> | 84% | 53,127 psi | 87% | 2657 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 55,042 psi | 90% | 2680 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 53,287 psi | 87% | 2746 fps | 99.6% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 42,003 psi | 69% | 2635 fps | 98.9% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 54,621 psi | 90% | 2720 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 53,432 psi | 88% | 2710 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 53,563 psi | 88% | 2776 fps | 98.2% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 34,432 psi | 57% | 2566 fps | 98.9% |
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% | 48,312 psi | 79% | 2520 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 41,060 psi | 67% | 2454 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 46,398 psi | 76% | 2582 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 46,398 psi | 76% | 2582 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 44,019 psi | 72% | 2484 fps | 95% |
| Accurate 3100 | <<locked>> | 98% | 37,449 psi | 61% | 2480 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 38,841 psi | 64% | 2451 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 32,416 psi | 53% | 2385 fps | 95.6% |
| ADI AR 2206H | <<locked>> | 80% | 44,585 psi | 73% | 2559 fps | 99.5% |
| ADI AR 2208 | <<locked>> | 80% | 37,884 psi | 62% | 2418 fps | 97.8% |
| ADI Benchmark 8208 | <<locked>> | 80% | 46,615 psi | 77% | 2566 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 46,963 psi | 77% | 2546 fps | 100% |
| Alliant Power Pro 2000-MR | 72.1 gr | 80% | 40,422 psi | 66% | 2592 fps | 98.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 37,536 psi | 62% | 2441 fps | 99% |
| Alliant Reloder-15 | <<locked>> | 80% | 40,277 psi | 66% | 2500 fps | 98.5% |
| Alliant Reloder-16 | <<locked>> | 84% | 33,040 psi | 54% | 2398 fps | 95.7% |
| Alliant Reloder-17 | <<locked>> | 80% | 32,329 psi | 53% | 2411 fps | 97.4% |
| Alliant Reloder-23 | <<locked>> | 90% | 28,529 psi | 47% | 2310 fps | 95.4% |
| Alliant Reloder-26 | <<locked>> | 94% | 34,896 psi | 57% | 2533 fps | 95.7% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 43,656 psi | 72% | 2562 fps | 98.7% |
| Bofors RP3 | <<locked>> | 80% | 37,072 psi | 61% | 2444 fps | 99% |
| Bofors RP7 | <<locked>> | 88% | 43,279 psi | 71% | 2516 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 48,240 psi | 79% | 2549 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 45,411 psi | 75% | 2589 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 50,154 psi | 82% | 2726 fps | 99.8% |
| Hodgdon H322 | <<locked>> | 80% | 49,516 psi | 81% | 2595 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 37,869 psi | 62% | 2444 fps | 96.7% |
| Hodgdon H414 | <<locked>> | 86% | 40,756 psi | 67% | 2556 fps | 95.3% |
| Hodgdon H4350 | <<locked>> | 94% | 48,095 psi | 79% | 2641 fps | 95.7% |
| Hodgdon H4895 | <<locked>> | 80% | 44,976 psi | 74% | 2569 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 28,442 psi | 47% | 2251 fps | 95.7% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 38,479 psi | 63% | 2497 fps | 99.3% |
| Hodgdon Superformance | 84.4 gr | 90% | 42,482 psi | 70% | 2608 fps | 95% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,440 psi | 43% | 1463 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 40,045 psi | 66% | 2464 fps | 99.1% |
| IMR 3031 | <<locked>> | 80% | 41,017 psi | 67% | 2500 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 37,130 psi | 61% | 2395 fps | 97.8% |
| IMR 4166 Enduron | <<locked>> | 84% | 41,742 psi | 69% | 2457 fps | 95.4% |
| IMR 4350 | <<locked>> | 92% | 43,236 psi | 71% | 2539 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 86% | 42,279 psi | 69% | 2497 fps | 95.4% |
| IMR 4831 | <<locked>> | 88% | 32,503 psi | 53% | 2369 fps | 95.7% |
| IMR 4895 | <<locked>> | 80% | 41,263 psi | 68% | 2530 fps | 99.1% |
| IMR 8208 XBR | <<locked>> | 80% | 46,615 psi | 77% | 2566 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 43,598 psi | 72% | 2536 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 44,512 psi | 73% | 2493 fps | 99.4% |
| Lovex S062 | <<locked>> | 80% | 39,653 psi | 65% | 2451 fps | 99.5% |
| Lovex S065 | <<locked>> | 84% | 36,912 psi | 61% | 2398 fps | 95.5% |
| Lovex S070 | <<locked>> | 88% | 39,552 psi | 65% | 2474 fps | 95% |
| Norma 201 | <<locked>> | 80% | 43,642 psi | 72% | 2513 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 43,976 psi | 72% | 2520 fps | 100% |
| Norma 203B | <<locked>> | 80% | 39,668 psi | 65% | 2490 fps | 98.8% |
| Norma 204 | <<locked>> | 96% | 48,979 psi | 80% | 2677 fps | 95.2% |
| Norma URP | <<locked>> | 84% | 32,982 psi | 54% | 2388 fps | 95.6% |
| Ramshot Big Game | <<locked>> | 80% | 39,131 psi | 64% | 2500 fps | 98.6% |
| Ramshot Hunter | <<locked>> | 90% | 39,088 psi | 64% | 2530 fps | 95.7% |
| Ramshot TAC | <<locked>> | 80% | 46,485 psi | 76% | 2572 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 45,934 psi | 75% | 2592 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 80% | 50,125 psi | 82% | 2608 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,716 psi | 44% | 1496 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 38,392 psi | 63% | 2431 fps | 95.1% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 42,337 psi | 70% | 2598 fps | 98.9% |
| ReloadSwiss RS 60 | 71 gr | 80% | 34,432 psi | 57% | 2474 fps | 99.7% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 32,227 psi | 53% | 2398 fps | 95% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 37,159 psi | 61% | 2516 fps | 96% |
| Rottweil R 901 | <<locked>> | 80% | 47,688 psi | 78% | 2549 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 41,481 psi | 68% | 2467 fps | 99.7% |
| Rottweil R 903 | <<locked>> | 80% | 34,896 psi | 57% | 2388 fps | 98.3% |
| Rottweil R 907 | <<locked>> | 88% | 43,279 psi | 71% | 2516 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 84% | 36,912 psi | 61% | 2398 fps | 95.5% |
| Shooters World Match Rifle | <<locked>> | 80% | 43,598 psi | 72% | 2536 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 39,653 psi | 65% | 2451 fps | 99.5% |
| Shooters World SW4350 | <<locked>> | 88% | 39,552 psi | 65% | 2474 fps | 95% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 35,853 psi | 59% | 2438 fps | 97.9% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 44,773 psi | 74% | 2549 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 43,018 psi | 71% | 2530 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 45,034 psi | 74% | 2464 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 37,449 psi | 61% | 2339 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 41,191 psi | 68% | 2444 fps | 95.3% |
| Somchem S321 | <<locked>> | 80% | 50,285 psi | 83% | 2638 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 44,614 psi | 73% | 2467 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 44,440 psi | 73% | 2543 fps | 99.4% |
| Somchem S355 | <<locked>> | 80% | 35,781 psi | 59% | 2395 fps | 98.3% |
| Somchem S365 | <<locked>> | 80% | 25,962 psi | 43% | 2238 fps | 96.1% |
| Somchem S385 | <<locked>> | 98% | 43,308 psi | 71% | 2582 fps | 95.2% |
| Unknown powder | <<locked>> | 82% | 33,678 psi | 55% | 2392 fps | 95% |
| Vihtavuori N130 | <<locked>> | 80% | 50,763 psi | 83% | 2516 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 45,324 psi | 74% | 2454 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 41,031 psi | 67% | 2448 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 41,553 psi | 68% | 2457 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 33,953 psi | 56% | 2336 fps | 99% |
| Vihtavuori N160 | <<locked>> | 82% | 32,314 psi | 53% | 2339 fps | 95.2% |
| Vihtavuori N530 | <<locked>> | 80% | 46,673 psi | 77% | 2559 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 39,972 psi | 66% | 2448 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 33,837 psi | 56% | 2392 fps | 95.6% |
| Vihtavuori N555 | <<locked>> | 90% | 30,356 psi | 50% | 2379 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 30,110 psi | 49% | 2264 fps | 96.6% |
| Winchester 748 | <<locked>> | 80% | 49,937 psi | 82% | 2661 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 40,756 psi | 67% | 2556 fps | 95.3% |
| Winchester StaBALL HD | <<locked>> | 94% | 28,500 psi | 47% | 2379 fps | 95.9% |
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 99 powders for .375 Blaser Mag. loaded with the .375 | 270gr | Barnes Banded Solid RN LG. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,844 fps; across all powders the maximum-charge window runs from 1,637 fps to 2,844 fps. Accurate 3100 gives the best case fill at 100 %, and 99 of the 99 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (420 MPa), the top charges use 57–90 %, 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 Power Pro 2000-MR, Hodgdon Superformance, ReloadSwiss RS 60 rank at the top here: for .375 Blaser Mag. with the .375 | 270gr | Barnes Banded Solid RN LG 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.