Load Specifications
Bullet Manufacturer:Speer
Bullet Weight:270 gr
Bullet Diameter:0.375"
Bullet Length:<<locked>>
Caliber:.375 Weath. Mag. load data
Case Length (l3):2.85"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:105 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:24"
Max. allowed Pressure:63,817 psi
Recommended Twist Rate:1:6.0
Load data in caliber .375 Weath. Mag. with .375 | 270gr | Speer Boat-Tail bullet and 105 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 60, Alliant Power Pro 2000-MR 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.
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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 86% | 55,883 psi | 88% | 2575 fps | 100% |
| Accurate 2460 | <<locked>> | 82% | 54,186 psi | 85% | 2602 fps | 100% |
| Accurate 2495 | <<locked>> | 92% | 57,638 psi | 90% | 2641 fps | 100% |
| Accurate 2520 | <<locked>> | 86% | 56,246 psi | 88% | 2664 fps | 100% |
| Accurate 2700 | <<locked>> | 92% | 57,377 psi | 90% | 2644 fps | 97.1% |
| Accurate 4064 | <<locked>> | 94% | 57,392 psi | 90% | 2684 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 53,171 psi | 83% | 2713 fps | 99.4% |
| ADI AR 2206H | <<locked>> | 88% | 54,926 psi | 86% | 2674 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 94% | 55,782 psi | 87% | 2667 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 88% | 57,464 psi | 90% | 2674 fps | 100% |
| Alliant AR-Comp | <<locked>> | 86% | 54,578 psi | 86% | 2605 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 82% | 55,825 psi | 87% | 2726 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 90% | 54,288 psi | 85% | 2782 fps | 99.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 94% | 55,521 psi | 87% | 2690 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 82% | 55,448 psi | 87% | 2579 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 92% | 56,173 psi | 88% | 2710 fps | 99.8% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 51,532 psi | 81% | 2717 fps | 99.4% |
| Alliant Reloder-17 | <<locked>> | 98% | 56,188 psi | 88% | 2808 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 36,724 psi | 58% | 2464 fps | 97.8% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 40,524 psi | 64% | 2602 fps | 96.7% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 57,392 psi | 90% | 2562 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 88% | 54,491 psi | 85% | 2687 fps | 99.5% |
| Bofors RP3 | <<locked>> | 94% | 56,159 psi | 88% | 2707 fps | 100% |
| Bofors RP7 | <<locked>> | 98% | 56,376 psi | 88% | 2674 fps | 97.2% |
| Hodgdon Benchmark | <<locked>> | 86% | 55,927 psi | 88% | 2612 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 88% | 56,637 psi | 89% | 2703 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 84% | 55,013 psi | 86% | 2746 fps | 99.8% |
| Hodgdon H322 | <<locked>> | 82% | 54,592 psi | 86% | 2618 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 55,753 psi | 87% | 2648 fps | 100% |
| Hodgdon H380 | <<locked>> | 94% | 57,290 psi | 90% | 2720 fps | 99.4% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 56,492 psi | 89% | 2766 fps | 97.9% |
| Hodgdon H4350 | <<locked>> | 98% | 57,450 psi | 90% | 2726 fps | 96.8% |
| Hodgdon H4895 | <<locked>> | 88% | 55,434 psi | 87% | 2680 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 47,761 psi | 75% | 2602 fps | 99.7% |
| Hodgdon LEVERevolution | <<locked>> | 90% | 54,549 psi | 85% | 2713 fps | 100% |
| Hodgdon Superformance | <<locked>> | 98% | 53,737 psi | 84% | 2743 fps | 96.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,273 psi | 55% | 1601 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 56,739 psi | 89% | 2684 fps | 100% |
| IMR 3031 | <<locked>> | 88% | 55,259 psi | 87% | 2664 fps | 100% |
| IMR 4064 | <<locked>> | 92% | 55,259 psi | 87% | 2654 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 90% | 55,535 psi | 87% | 2635 fps | 97.6% |
| IMR 4198 | <<locked>> | 82% | 55,579 psi | 87% | 2536 fps | 100% |
| IMR 4350ᴾ | <<locked>> | 100% | 53,011 psi | 83% | 2648 fps | 96.6% |
| IMR 4451 Enduron | <<locked>> | 96% | 55,085 psi | 86% | 2657 fps | 97.4% |
| IMR 4831ᴾ | <<locked>> | 100% | 50,386 psi | 79% | 2654 fps | 99.1% |
| IMR 4895 | <<locked>> | 92% | 57,638 psi | 90% | 2740 fps | 100% |
| IMR 8208 XBR | <<locked>> | 88% | 57,464 psi | 90% | 2674 fps | 100% |
| Lovex D073.5 | <<locked>> | 82% | 54,186 psi | 85% | 2615 fps | 100% |
| Lovex D073.6 | <<locked>> | 88% | 54,476 psi | 85% | 2651 fps | 100% |
| Lovex S060 | <<locked>> | 88% | 54,636 psi | 86% | 2605 fps | 99.9% |
| Lovex S062 | <<locked>> | 92% | 55,027 psi | 86% | 2651 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 57,493 psi | 90% | 2697 fps | 98.9% |
| Lovex S070ᴾ | <<locked>> | 100% | 54,940 psi | 86% | 2680 fps | 97.8% |
| Norma 201 | <<locked>> | 90% | 57,043 psi | 89% | 2667 fps | 100% |
| Norma 202 | <<locked>> | 90% | 57,508 psi | 90% | 2667 fps | 100% |
| Norma 203B | <<locked>> | 92% | 55,332 psi | 87% | 2697 fps | 99.9% |
| Norma URPᴾ | <<locked>> | 100% | 52,605 psi | 82% | 2703 fps | 99.3% |
| Ramshot Big Game | <<locked>> | 92% | 55,941 psi | 88% | 2723 fps | 99.9% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 51,430 psi | 81% | 2697 fps | 97.8% |
| Ramshot TAC | <<locked>> | 86% | 54,215 psi | 85% | 2644 fps | 98.7% |
| Ramshot Wild Boar | <<locked>> | 88% | 57,392 psi | 90% | 2713 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 84% | 54,882 psi | 86% | 2628 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,650 psi | 56% | 1637 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 84% | 57,130 psi | 90% | 2657 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 57,667 psi | 90% | 2700 fps | 98.5% |
| ReloadSwiss RS 52 | <<locked>> | 90% | 56,710 psi | 89% | 2776 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 96% | 55,999 psi | 88% | 2805 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 52,736 psi | 83% | 2733 fps | 99.2% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 52,924 psi | 83% | 2759 fps | 98.9% |
| Rottweil R 901 | <<locked>> | 86% | 54,868 psi | 86% | 2605 fps | 100% |
| Rottweil R 902 | <<locked>> | 92% | 57,363 psi | 90% | 2664 fps | 100% |
| Rottweil R 903 | <<locked>> | 96% | 55,796 psi | 87% | 2694 fps | 100% |
| Rottweil R 907 | <<locked>> | 98% | 56,376 psi | 88% | 2674 fps | 97.2% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 57,493 psi | 90% | 2697 fps | 98.9% |
| Shooters World Match Rifle | <<locked>> | 88% | 54,476 psi | 85% | 2651 fps | 100% |
| Shooters World Precision | <<locked>> | 92% | 55,027 psi | 86% | 2651 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 54,940 psi | 86% | 2680 fps | 97.8% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 56,623 psi | 89% | 2628 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 96% | 57,696 psi | 90% | 2756 fps | 100% |
| SNPE Vectan SP 3 | <<locked>> | 82% | 56,536 psi | 89% | 2598 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 88% | 56,246 psi | 88% | 2674 fps | 99.2% |
| SNPE Vectan SP 9 | <<locked>> | 90% | 56,739 psi | 89% | 2694 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 88% | 55,434 psi | 87% | 2566 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 94% | 55,332 psi | 87% | 2562 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 54,592 psi | 86% | 2605 fps | 97.4% |
| Somchem S321 | <<locked>> | 84% | 55,129 psi | 86% | 2657 fps | 100% |
| Somchem S335 | <<locked>> | 88% | 54,592 psi | 86% | 2562 fps | 100% |
| Somchem S341 | <<locked>> | 88% | 55,637 psi | 87% | 2664 fps | 99.9% |
| Somchem S355 | <<locked>> | 96% | 56,304 psi | 88% | 2694 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 46,920 psi | 74% | 2654 fps | 100% |
| Vihtavuori N130 | <<locked>> | 84% | 55,201 psi | 87% | 2530 fps | 100% |
| Vihtavuori N133 | <<locked>> | 88% | 55,593 psi | 87% | 2552 fps | 100% |
| Vihtavuori N135 | <<locked>> | 92% | 57,101 psi | 89% | 2628 fps | 100% |
| Vihtavuori N140 | <<locked>> | 90% | 54,592 psi | 86% | 2602 fps | 100% |
| Vihtavuori N150 | <<locked>> | 96% | 54,230 psi | 85% | 2628 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 55,100 psi | 86% | 2700 fps | 99.4% |
| Vihtavuori N530 | <<locked>> | 86% | 54,476 psi | 85% | 2625 fps | 100% |
| Vihtavuori N540 | <<locked>> | 92% | 56,275 psi | 88% | 2648 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 54,070 psi | 85% | 2703 fps | 99.2% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 39,523 psi | 62% | 2536 fps | 97.7% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 55,782 psi | 87% | 2684 fps | 100% |
| Winchester 748 | <<locked>> | 86% | 54,099 psi | 85% | 2671 fps | 100% |
| Winchester 760ᴾ | <<locked>> | 100% | 56,695 psi | 89% | 2766 fps | 98% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 32,750 psi | 51% | 2448 fps | 97% |
| Winchester StaBALL Match | <<locked>> | 90% | 56,623 psi | 89% | 2703 fps | 100% |
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% | 46,427 psi | 73% | 2448 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 50,691 psi | 79% | 2556 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 39,146 psi | 61% | 2379 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 45,818 psi | 72% | 2516 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 50,357 psi | 79% | 2543 fps | 95.7% |
| Accurate 4064 | <<locked>> | 80% | 37,028 psi | 58% | 2372 fps | 99.9% |
| Accurate 4350 | <<locked>> | 88% | 35,244 psi | 55% | 2398 fps | 95.7% |
| ADI AR 2206H | <<locked>> | 80% | 42,815 psi | 67% | 2477 fps | 98.8% |
| ADI AR 2208 | <<locked>> | 80% | 36,448 psi | 57% | 2336 fps | 96.6% |
| ADI Benchmark 8208 | <<locked>> | 80% | 44,831 psi | 70% | 2484 fps | 99.7% |
| Alliant AR-Comp | <<locked>> | 80% | 44,657 psi | 70% | 2474 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 52,359 psi | 82% | 2674 fps | 99.9% |
| Alliant Power Pro 2000-MR | 69.3 gr | 80% | 38,624 psi | 61% | 2493 fps | 97% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 35,853 psi | 56% | 2356 fps | 98.1% |
| Alliant Reloder-10x | <<locked>> | 80% | 52,301 psi | 82% | 2536 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 38,551 psi | 60% | 2415 fps | 97.4% |
| Alliant Reloder-16 | <<locked>> | 88% | 35,723 psi | 56% | 2408 fps | 95.8% |
| Alliant Reloder-17 | 68.3 gr | 80% | 30,937 psi | 48% | 2316 fps | 95.7% |
| Alliant Reloder-23 | <<locked>> | 94% | 30,603 psi | 48% | 2313 fps | 95.3% |
| Alliant Reloder-26 | <<locked>> | 98% | 37,913 psi | 59% | 2543 fps | 95.7% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 53,795 psi | 84% | 2516 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 41,756 psi | 65% | 2477 fps | 97.6% |
| Bofors RP3 | <<locked>> | 80% | 35,375 psi | 55% | 2359 fps | 98.1% |
| Bofors RP7 | <<locked>> | 92% | 46,804 psi | 73% | 2523 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 46,673 psi | 73% | 2474 fps | 99.9% |
| Hodgdon BL-C2 | <<locked>> | 80% | 43,308 psi | 68% | 2503 fps | 99.8% |
| Hodgdon CFE223 | <<locked>> | 80% | 47,659 psi | 75% | 2635 fps | 99.2% |
| Hodgdon H322 | <<locked>> | 80% | 51,213 psi | 80% | 2572 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 51,996 psi | 81% | 2595 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 36,274 psi | 57% | 2359 fps | 95.3% |
| Hodgdon H414 | <<locked>> | 92% | 43,366 psi | 68% | 2552 fps | 95.1% |
| Hodgdon H4350 | <<locked>> | 94% | 50,618 psi | 79% | 2625 fps | 95.3% |
| Hodgdon H4895 | <<locked>> | 80% | 43,149 psi | 68% | 2487 fps | 99.2% |
| Hodgdon Hybrid 100V | <<locked>> | 86% | 30,806 psi | 48% | 2264 fps | 95.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 39,030 psi | 61% | 2457 fps | 98.9% |
| Hodgdon Superformance | <<locked>> | 94% | 46,615 psi | 73% | 2625 fps | 95.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,223 psi | 41% | 1427 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 41,481 psi | 65% | 2441 fps | 98.9% |
| IMR 3031 | <<locked>> | 80% | 42,641 psi | 67% | 2484 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 38,247 psi | 60% | 2369 fps | 97.4% |
| IMR 4166 Enduron | <<locked>> | 84% | 46,137 psi | 72% | 2484 fps | 95.6% |
| IMR 4198 | <<locked>> | 80% | 52,591 psi | 82% | 2500 fps | 100% |
| IMR 4350 | <<locked>> | 96% | 46,876 psi | 73% | 2549 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 90% | 45,788 psi | 72% | 2510 fps | 95.5% |
| IMR 4831 | <<locked>> | 88% | 34,142 psi | 54% | 2356 fps | 95.3% |
| IMR 4895 | <<locked>> | 80% | 39,479 psi | 62% | 2444 fps | 98.2% |
| IMR 8208 XBR | <<locked>> | 80% | 44,831 psi | 70% | 2484 fps | 99.7% |
| Lovex D073.5 | <<locked>> | 80% | 50,546 psi | 79% | 2566 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 41,713 psi | 65% | 2457 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 43,018 psi | 67% | 2418 fps | 98.8% |
| Lovex S062 | <<locked>> | 80% | 38,058 psi | 60% | 2372 fps | 98.9% |
| Lovex S065 | <<locked>> | 88% | 39,885 psi | 63% | 2408 fps | 95.5% |
| Lovex S070 | <<locked>> | 92% | 42,772 psi | 67% | 2484 fps | 95.1% |
| Norma 201 | <<locked>> | 80% | 41,989 psi | 66% | 2434 fps | 99.4% |
| Norma 202 | <<locked>> | 80% | 42,119 psi | 66% | 2441 fps | 100% |
| Norma 203B | <<locked>> | 80% | 37,971 psi | 60% | 2405 fps | 97.8% |
| Norma URP | <<locked>> | 88% | 35,665 psi | 56% | 2398 fps | 95.6% |
| Ramshot Big Game | <<locked>> | 80% | 37,275 psi | 58% | 2411 fps | 97.4% |
| Ramshot Hunter | <<locked>> | 94% | 42,438 psi | 67% | 2539 fps | 95.7% |
| Ramshot TAC | <<locked>> | 80% | 44,686 psi | 70% | 2487 fps | 97% |
| Ramshot Wild Boar | <<locked>> | 80% | 44,005 psi | 69% | 2507 fps | 98.9% |
| Ramshot X-Terminator | <<locked>> | 80% | 48,399 psi | 76% | 2530 fps | 99.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,658 psi | 42% | 1467 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 50,111 psi | 79% | 2559 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 41,872 psi | 66% | 2448 fps | 95.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 40,176 psi | 63% | 2507 fps | 97.8% |
| ReloadSwiss RS 60 | 68.3 gr | 80% | 32,938 psi | 52% | 2382 fps | 98.9% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 35,056 psi | 55% | 2411 fps | 95.1% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 37,927 psi | 59% | 2474 fps | 95.1% |
| Rottweil R 901 | <<locked>> | 80% | 45,832 psi | 72% | 2470 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 39,842 psi | 62% | 2385 fps | 99.1% |
| Rottweil R 903 | <<locked>> | 80% | 33,330 psi | 52% | 2306 fps | 97.2% |
| Rottweil R 907 | <<locked>> | 92% | 46,804 psi | 73% | 2523 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 88% | 39,885 psi | 63% | 2408 fps | 95.5% |
| Shooters World Match Rifle | <<locked>> | 80% | 41,713 psi | 65% | 2457 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 38,058 psi | 60% | 2372 fps | 98.9% |
| Shooters World SW4350 | <<locked>> | 92% | 42,772 psi | 67% | 2484 fps | 95.1% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 52,968 psi | 83% | 2579 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 34,229 psi | 54% | 2349 fps | 96.5% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 53,040 psi | 83% | 2556 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 42,830 psi | 67% | 2461 fps | 97.1% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 41,263 psi | 65% | 2448 fps | 98.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 43,308 psi | 68% | 2388 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 35,911 psi | 56% | 2267 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 44,802 psi | 70% | 2457 fps | 95.3% |
| Somchem S321 | <<locked>> | 80% | 48,269 psi | 76% | 2559 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 43,004 psi | 67% | 2395 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 42,511 psi | 67% | 2461 fps | 98.6% |
| Somchem S355 | <<locked>> | 80% | 34,272 psi | 54% | 2313 fps | 97.2% |
| Somchem S365 | <<locked>> | 82% | 26,339 psi | 41% | 2195 fps | 95.1% |
| Vihtavuori N130 | <<locked>> | 80% | 48,936 psi | 77% | 2448 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 43,584 psi | 68% | 2385 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 39,131 psi | 61% | 2372 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 39,914 psi | 63% | 2382 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 32,518 psi | 51% | 2257 fps | 98% |
| Vihtavuori N160 | <<locked>> | 86% | 35,099 psi | 55% | 2352 fps | 95.3% |
| Vihtavuori N530 | <<locked>> | 80% | 44,831 psi | 70% | 2480 fps | 99.7% |
| Vihtavuori N540 | <<locked>> | 80% | 38,392 psi | 60% | 2372 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 88% | 36,608 psi | 57% | 2402 fps | 95.7% |
| Vihtavuori N555 | <<locked>> | 94% | 32,692 psi | 51% | 2385 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 82% | 30,879 psi | 48% | 2231 fps | 95.9% |
| Winchester 748 | <<locked>> | 80% | 44,237 psi | 69% | 2523 fps | 99.9% |
| Winchester 760 | <<locked>> | 92% | 43,569 psi | 68% | 2556 fps | 95.1% |
| Winchester StaBALL HD | <<locked>> | 98% | 30,719 psi | 48% | 2385 fps | 95.7% |
| Winchester StaBALL Match | <<locked>> | 80% | 40,553 psi | 64% | 2448 fps | 98.8% |
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 118 powders for .375 Weath. Mag. loaded with the .375 | 270gr | Speer Boat-Tail. Alliant Reloder-17 delivers the highest muzzle velocity at 2,808 fps; across all powders the maximum-charge window runs from 1,601 fps to 2,808 fps. Accurate 3100 gives the best case fill at 100 %, and 118 of the 118 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 49–90 %, 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, Accurate 4350, ADI AR 2209 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, Alliant Power Pro 2000-MR, Alliant Reloder-17 rank at the top here: for .375 Weath. Mag. with the .375 | 270gr | Speer Boat-Tail they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate 3100, ADI AR 2209, Alliant Reloder-19 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.