Load Specifications
Bullet:.375 | 270gr | Swift A-Frame
Bullet Manufacturer:Swift
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 | Swift A-Frame bullet and 104 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, Alliant Reloder-17 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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 86% | 56,695 psi | 89% | 2592 fps | 100% |
| Accurate 2460 | <<locked>> | 82% | 55,143 psi | 86% | 2618 fps | 100% |
| Accurate 2495 | <<locked>> | 90% | 55,114 psi | 86% | 2615 fps | 100% |
| Accurate 2520 | <<locked>> | 86% | 57,217 psi | 90% | 2680 fps | 100% |
| Accurate 2700 | <<locked>> | 90% | 54,665 psi | 86% | 2615 fps | 96.7% |
| Accurate 4064 | <<locked>> | 92% | 55,143 psi | 86% | 2661 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 54,462 psi | 85% | 2736 fps | 99.5% |
| ADI AR 2206H | <<locked>> | 88% | 55,825 psi | 87% | 2690 fps | 100% |
| ADI AR 2208 | <<locked>> | 94% | 56,753 psi | 89% | 2690 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 86% | 54,795 psi | 86% | 2644 fps | 100% |
| Alliant AR-Comp | <<locked>> | 86% | 55,564 psi | 87% | 2618 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 82% | 56,768 psi | 89% | 2746 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 90% | 55,317 psi | 87% | 2805 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 94% | 56,608 psi | 89% | 2710 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 82% | 56,420 psi | 88% | 2595 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 92% | 57,276 psi | 90% | 2730 fps | 99.9% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 52,591 psi | 82% | 2740 fps | 99.6% |
| Alliant Reloder-17 | <<locked>> | 98% | 57,261 psi | 90% | 2828 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 37,391 psi | 59% | 2487 fps | 98.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 41,452 psi | 65% | 2628 fps | 97.1% |
| Baschieri & Pellagri 107 | <<locked>> | 88% | 55,463 psi | 87% | 2707 fps | 99.7% |
| Bofors RP3 | <<locked>> | 94% | 57,232 psi | 90% | 2726 fps | 100% |
| Bofors RP7 | <<locked>> | 98% | 57,464 psi | 90% | 2697 fps | 97.5% |
| Hodgdon Benchmark | <<locked>> | 86% | 56,797 psi | 89% | 2631 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 88% | 57,711 psi | 90% | 2723 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 84% | 56,130 psi | 88% | 2769 fps | 99.9% |
| Hodgdon H322 | <<locked>> | 82% | 55,434 psi | 87% | 2635 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 56,666 psi | 89% | 2664 fps | 100% |
| Hodgdon H380 | <<locked>> | 92% | 54,810 psi | 86% | 2690 fps | 99.3% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 57,667 psi | 90% | 2785 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 96% | 54,955 psi | 86% | 2697 fps | 96.4% |
| Hodgdon H4895 | <<locked>> | 88% | 56,376 psi | 88% | 2700 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 48,646 psi | 76% | 2621 fps | 99.8% |
| Hodgdon LEVERevolution | <<locked>> | 90% | 55,637 psi | 87% | 2733 fps | 100% |
| Hodgdon Superformance | <<locked>> | 98% | 54,781 psi | 86% | 2769 fps | 97.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,360 psi | 55% | 1608 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 57,638 psi | 90% | 2703 fps | 100% |
| IMR 3031 | <<locked>> | 88% | 56,159 psi | 88% | 2680 fps | 100% |
| IMR 4064 | <<locked>> | 92% | 56,333 psi | 88% | 2674 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 90% | 56,492 psi | 89% | 2657 fps | 97.9% |
| IMR 4198 | <<locked>> | 82% | 56,362 psi | 88% | 2552 fps | 100% |
| IMR 4350ᴾ | <<locked>> | 100% | 53,983 psi | 85% | 2667 fps | 96.9% |
| IMR 4451 Enduron | <<locked>> | 96% | 55,956 psi | 88% | 2677 fps | 97.7% |
| IMR 4831ᴾ | <<locked>> | 100% | 51,561 psi | 81% | 2677 fps | 99.3% |
| IMR 4895 | <<locked>> | 90% | 55,303 psi | 87% | 2713 fps | 100% |
| IMR 8208 XBR | <<locked>> | 86% | 54,795 psi | 86% | 2644 fps | 100% |
| Lovex D073.5 | <<locked>> | 82% | 55,114 psi | 86% | 2631 fps | 100% |
| Lovex D073.6 | <<locked>> | 88% | 55,405 psi | 87% | 2667 fps | 100% |
| Lovex S060 | <<locked>> | 88% | 55,463 psi | 87% | 2621 fps | 99.9% |
| Lovex S062 | <<locked>> | 92% | 55,912 psi | 88% | 2667 fps | 100% |
| Lovex S065 | <<locked>> | 98% | 55,027 psi | 86% | 2671 fps | 98.7% |
| Lovex S070ᴾ | <<locked>> | 100% | 55,796 psi | 87% | 2700 fps | 98% |
| Norma 201 | <<locked>> | 88% | 54,563 psi | 86% | 2638 fps | 100% |
| Norma 202 | <<locked>> | 88% | 55,056 psi | 86% | 2641 fps | 100% |
| Norma 203B | <<locked>> | 92% | 56,434 psi | 88% | 2720 fps | 100% |
| Norma URPᴾ | <<locked>> | 100% | 53,534 psi | 84% | 2723 fps | 99.4% |
| Ramshot Big Game | <<locked>> | 92% | 57,101 psi | 89% | 2746 fps | 100% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 52,373 psi | 82% | 2720 fps | 98.1% |
| Ramshot TAC | <<locked>> | 86% | 55,158 psi | 86% | 2664 fps | 98.9% |
| Ramshot Wild Boar | <<locked>> | 86% | 54,650 psi | 86% | 2680 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 84% | 55,912 psi | 88% | 2648 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,911 psi | 56% | 1650 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 82% | 54,462 psi | 85% | 2628 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 55,187 psi | 86% | 2674 fps | 98.2% |
| ReloadSwiss RS 52 | <<locked>> | 88% | 54,157 psi | 85% | 2746 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 96% | 57,188 psi | 90% | 2828 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 54,085 psi | 85% | 2759 fps | 99.4% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 54,041 psi | 85% | 2782 fps | 99.2% |
| Rottweil R 901 | <<locked>> | 86% | 55,666 psi | 87% | 2621 fps | 100% |
| Rottweil R 902 | <<locked>> | 90% | 55,071 psi | 86% | 2638 fps | 100% |
| Rottweil R 903 | <<locked>> | 96% | 57,087 psi | 89% | 2717 fps | 100% |
| Rottweil R 907 | <<locked>> | 98% | 57,464 psi | 90% | 2697 fps | 97.5% |
| Shooters World Long Rifle | <<locked>> | 98% | 55,027 psi | 86% | 2671 fps | 98.7% |
| Shooters World Match Rifle | <<locked>> | 88% | 55,405 psi | 87% | 2667 fps | 100% |
| Shooters World Precision | <<locked>> | 92% | 55,912 psi | 88% | 2667 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 55,796 psi | 87% | 2700 fps | 98% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 57,725 psi | 90% | 2648 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 94% | 55,187 psi | 86% | 2726 fps | 99.9% |
| SNPE Vectan SP 3 | <<locked>> | 82% | 57,261 psi | 90% | 2615 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 88% | 57,246 psi | 90% | 2694 fps | 99.4% |
| SNPE Vectan SP 9 | <<locked>> | 88% | 54,215 psi | 85% | 2664 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 88% | 56,188 psi | 88% | 2582 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 94% | 56,188 psi | 88% | 2579 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 55,651 psi | 87% | 2628 fps | 97.7% |
| Somchem S321 | <<locked>> | 84% | 56,173 psi | 88% | 2677 fps | 100% |
| Somchem S335 | <<locked>> | 88% | 55,492 psi | 87% | 2579 fps | 100% |
| Somchem S341 | <<locked>> | 88% | 56,681 psi | 89% | 2684 fps | 100% |
| Somchem S355 | <<locked>> | 96% | 57,348 psi | 90% | 2713 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 48,037 psi | 75% | 2677 fps | 100% |
| Vihtavuori N130 | <<locked>> | 84% | 56,057 psi | 88% | 2546 fps | 100% |
| Vihtavuori N133 | <<locked>> | 88% | 56,333 psi | 88% | 2566 fps | 100% |
| Vihtavuori N135 | <<locked>> | 90% | 54,607 psi | 86% | 2605 fps | 100% |
| Vihtavuori N140 | <<locked>> | 90% | 55,463 psi | 87% | 2618 fps | 100% |
| Vihtavuori N150 | <<locked>> | 96% | 55,448 psi | 87% | 2651 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 56,275 psi | 88% | 2720 fps | 99.6% |
| Vihtavuori N530 | <<locked>> | 86% | 55,390 psi | 87% | 2644 fps | 100% |
| Vihtavuori N540 | <<locked>> | 92% | 57,261 psi | 90% | 2664 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 55,172 psi | 86% | 2726 fps | 99.4% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 40,567 psi | 64% | 2559 fps | 98.1% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 56,840 psi | 89% | 2703 fps | 100% |
| Winchester 748 | <<locked>> | 86% | 55,259 psi | 87% | 2690 fps | 100% |
| Winchester 760 | <<locked>> | 98% | 54,143 psi | 85% | 2736 fps | 97.7% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 33,417 psi | 52% | 2474 fps | 97.6% |
| Winchester StaBALL Match | <<locked>> | 90% | 57,667 psi | 90% | 2723 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% | 47,268 psi | 74% | 2467 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 51,663 psi | 81% | 2572 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 39,885 psi | 63% | 2395 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 46,775 psi | 73% | 2536 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 47,964 psi | 75% | 2510 fps | 95.3% |
| Accurate 4064 | <<locked>> | 80% | 37,710 psi | 59% | 2388 fps | 100% |
| Accurate 4350 | <<locked>> | 86% | 33,620 psi | 53% | 2365 fps | 95.2% |
| ADI AR 2206H | <<locked>> | 80% | 43,555 psi | 68% | 2493 fps | 98.9% |
| ADI AR 2208 | <<locked>> | 80% | 36,970 psi | 58% | 2352 fps | 96.9% |
| ADI Benchmark 8208 | <<locked>> | 80% | 45,571 psi | 71% | 2503 fps | 99.8% |
| Alliant AR-Comp | <<locked>> | 80% | 45,614 psi | 71% | 2490 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 53,301 psi | 84% | 2694 fps | 100% |
| Alliant Power Pro 2000-MR | 70.6 gr | 80% | 39,407 psi | 62% | 2516 fps | 97.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 36,535 psi | 57% | 2375 fps | 98.3% |
| Alliant Reloder-10x | <<locked>> | 80% | 53,055 psi | 83% | 2552 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 39,276 psi | 62% | 2434 fps | 97.7% |
| Alliant Reloder-16 | <<locked>> | 86% | 34,272 psi | 54% | 2379 fps | 95.3% |
| Alliant Reloder-17 | 69.5 gr | 80% | 31,459 psi | 49% | 2336 fps | 96.1% |
| Alliant Reloder-23 | <<locked>> | 94% | 31,270 psi | 49% | 2336 fps | 95.8% |
| Alliant Reloder-26 | <<locked>> | 96% | 36,216 psi | 57% | 2510 fps | 95.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 42,511 psi | 67% | 2497 fps | 97.9% |
| Bofors RP3 | <<locked>> | 80% | 36,085 psi | 57% | 2375 fps | 98.3% |
| Bofors RP7 | <<locked>> | 92% | 47,732 psi | 75% | 2546 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 80% | 47,413 psi | 74% | 2493 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 44,208 psi | 69% | 2523 fps | 99.9% |
| Hodgdon CFE223 | <<locked>> | 80% | 48,631 psi | 76% | 2657 fps | 99.3% |
| Hodgdon H322 | <<locked>> | 80% | 52,083 psi | 82% | 2592 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 52,924 psi | 83% | 2615 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 36,956 psi | 58% | 2379 fps | 95.7% |
| Hodgdon H414 | <<locked>> | 92% | 44,309 psi | 69% | 2575 fps | 95.5% |
| Hodgdon H4350 | <<locked>> | 94% | 51,503 psi | 81% | 2648 fps | 95.7% |
| Hodgdon H4895 | <<locked>> | 80% | 43,918 psi | 69% | 2507 fps | 99.3% |
| Hodgdon Hybrid 100V | <<locked>> | 84% | 29,428 psi | 46% | 2234 fps | 95.3% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 39,711 psi | 62% | 2477 fps | 99% |
| Hodgdon Superformance | <<locked>> | 94% | 47,442 psi | 74% | 2648 fps | 95.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,295 psi | 41% | 1437 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 42,177 psi | 66% | 2461 fps | 99% |
| IMR 3031 | <<locked>> | 80% | 43,352 psi | 68% | 2500 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 38,812 psi | 61% | 2382 fps | 97.6% |
| IMR 4166 Enduron | <<locked>> | 82% | 44,048 psi | 69% | 2454 fps | 95.2% |
| IMR 4198 | <<locked>> | 80% | 53,185 psi | 83% | 2513 fps | 100% |
| IMR 4350 | <<locked>> | 96% | 47,718 psi | 75% | 2569 fps | 95.6% |
| IMR 4451 Enduron | <<locked>> | 88% | 43,816 psi | 69% | 2477 fps | 95% |
| IMR 4831 | <<locked>> | 88% | 34,896 psi | 55% | 2379 fps | 95.7% |
| IMR 4895 | <<locked>> | 80% | 40,234 psi | 63% | 2464 fps | 98.4% |
| IMR 8208 XBR | <<locked>> | 80% | 45,571 psi | 71% | 2503 fps | 99.8% |
| Lovex D073.5 | <<locked>> | 80% | 51,503 psi | 81% | 2582 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 42,482 psi | 67% | 2477 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 43,714 psi | 69% | 2438 fps | 99% |
| Lovex S062 | <<locked>> | 80% | 38,783 psi | 61% | 2392 fps | 99.1% |
| Lovex S065 | <<locked>> | 86% | 38,261 psi | 60% | 2382 fps | 95.1% |
| Lovex S070 | <<locked>> | 92% | 43,671 psi | 68% | 2507 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 42,598 psi | 67% | 2451 fps | 99.5% |
| Norma 202 | <<locked>> | 80% | 42,859 psi | 67% | 2461 fps | 100% |
| Norma 203B | <<locked>> | 80% | 38,653 psi | 61% | 2425 fps | 98.1% |
| Norma URP | <<locked>> | 86% | 34,185 psi | 54% | 2369 fps | 95.2% |
| Ramshot Big Game | <<locked>> | 80% | 38,043 psi | 60% | 2434 fps | 97.7% |
| Ramshot Hunter | <<locked>> | 92% | 40,553 psi | 64% | 2510 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 45,455 psi | 71% | 2507 fps | 97.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 44,788 psi | 70% | 2526 fps | 99.1% |
| Ramshot X-Terminator | <<locked>> | 80% | 49,066 psi | 77% | 2546 fps | 99.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,731 psi | 42% | 1473 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 51,097 psi | 80% | 2579 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 42,670 psi | 67% | 2467 fps | 95.6% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 40,973 psi | 64% | 2526 fps | 98.1% |
| ReloadSwiss RS 60 | 69.5 gr | 80% | 33,475 psi | 52% | 2402 fps | 99.1% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 35,839 psi | 56% | 2434 fps | 95.5% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 38,653 psi | 61% | 2497 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 46,673 psi | 73% | 2490 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 40,611 psi | 64% | 2405 fps | 99.3% |
| Rottweil R 903 | <<locked>> | 80% | 33,881 psi | 53% | 2323 fps | 97.4% |
| Rottweil R 907 | <<locked>> | 92% | 47,732 psi | 75% | 2546 fps | 95.5% |
| Shooters World Long Rifle | <<locked>> | 86% | 38,261 psi | 60% | 2382 fps | 95.1% |
| Shooters World Match Rifle | <<locked>> | 80% | 42,482 psi | 67% | 2477 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 38,783 psi | 61% | 2392 fps | 99.1% |
| Shooters World SW4350 | <<locked>> | 92% | 43,671 psi | 68% | 2507 fps | 95.5% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 53,911 psi | 84% | 2598 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 34,809 psi | 55% | 2369 fps | 96.8% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 53,998 psi | 85% | 2575 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 43,656 psi | 68% | 2484 fps | 97.4% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 41,916 psi | 66% | 2464 fps | 98.6% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 44,077 psi | 69% | 2408 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 36,622 psi | 57% | 2283 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 45,730 psi | 72% | 2477 fps | 95.7% |
| Somchem S321 | <<locked>> | 80% | 49,095 psi | 77% | 2575 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 43,569 psi | 68% | 2408 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 43,337 psi | 68% | 2480 fps | 98.8% |
| Somchem S355 | <<locked>> | 80% | 34,838 psi | 55% | 2329 fps | 97.5% |
| Somchem S365 | <<locked>> | 82% | 26,963 psi | 42% | 2221 fps | 95.6% |
| Vihtavuori N130 | <<locked>> | 80% | 49,806 psi | 78% | 2464 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 44,382 psi | 70% | 2405 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 40,030 psi | 63% | 2392 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 40,509 psi | 63% | 2398 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 33,054 psi | 52% | 2270 fps | 98.2% |
| Vihtavuori N160 | <<locked>> | 86% | 35,694 psi | 56% | 2372 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 80% | 45,629 psi | 72% | 2500 fps | 99.8% |
| Vihtavuori N540 | <<locked>> | 80% | 39,030 psi | 61% | 2388 fps | 99.9% |
| Vihtavuori N550 | <<locked>> | 86% | 35,128 psi | 55% | 2372 fps | 95.2% |
| Vihtavuori N555 | <<locked>> | 92% | 31,343 psi | 49% | 2356 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 29,399 psi | 46% | 2198 fps | 95.3% |
| Winchester 748 | <<locked>> | 80% | 45,194 psi | 71% | 2543 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 44,469 psi | 70% | 2575 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 96% | 29,457 psi | 46% | 2349 fps | 95.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 41,408 psi | 65% | 2470 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 104 powders for .375 Weath. Mag. loaded with the .375 | 270gr | Swift A-Frame. Alliant Reloder-17 delivers the highest muzzle velocity at 2,828 fps; across all powders the maximum-charge window runs from 1,608 fps to 2,828 fps. Accurate 4350 gives the best case fill at 100 %, and 104 of the 104 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 52–90 %, 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 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, Alliant Reloder-17, ReloadSwiss RS 60 rank at the top here: for .375 Weath. Mag. with the .375 | 270gr | Swift A-Frame 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.