Load Specifications
Bullet:.375 | 270gr | Swift A-Frame
Bullet Manufacturer:Swift
Bullet Weight:270 gr
Bullet Diameter:0.375"
Bullet Length:<<locked>>
Caliber:.375 H&H Mag. load data
Case Length (l3):2.859"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:95.3 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:24"
Max. allowed Pressure:62,366 psi
Recommended Twist Rate:1:6.0
Load data in caliber .375 H&H 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, ReloadSwiss RS 60 and ReloadSwiss RS 52.
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>> | 88% | 55,434 psi | 89% | 2530 fps | 100% |
| Accurate 2460 | <<locked>> | 84% | 53,809 psi | 86% | 2552 fps | 100% |
| Accurate 2495 | <<locked>> | 92% | 52,837 psi | 85% | 2546 fps | 100% |
| Accurate 2520 | <<locked>> | 88% | 53,519 psi | 86% | 2595 fps | 100% |
| Accurate 2520 | <<locked>> | 88% | 53,519 psi | 86% | 2595 fps | 100% |
| Accurate 4064 | <<locked>> | 96% | 55,999 psi | 90% | 2625 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 48,124 psi | 77% | 2592 fps | 98.3% |
| Accurate LT-30 | <<locked>> | 82% | 54,882 psi | 88% | 2477 fps | 100% |
| Accurate LT-32 | <<locked>> | 82% | 55,303 psi | 89% | 2500 fps | 100% |
| ADI AR 2206H | <<locked>> | 90% | 54,230 psi | 87% | 2615 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 96% | 55,172 psi | 88% | 2608 fps | 99.4% |
| ADI AR 2219 | <<locked>> | 82% | 55,535 psi | 89% | 2585 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 88% | 53,548 psi | 86% | 2572 fps | 100% |
| Alliant AR-Comp | <<locked>> | 88% | 53,606 psi | 86% | 2556 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 84% | 55,158 psi | 88% | 2671 fps | 99.9% |
| Alliant Power Pro 2000-MR | <<locked>> | 92% | 53,548 psi | 86% | 2717 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 96% | 54,476 psi | 87% | 2628 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 84% | 55,245 psi | 89% | 2533 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 94% | 55,390 psi | 89% | 2651 fps | 99.6% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 47,500 psi | 76% | 2595 fps | 98.4% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 54,911 psi | 88% | 2740 fps | 100% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 53,882 psi | 86% | 2477 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 90% | 53,838 psi | 86% | 2628 fps | 99.1% |
| Bofors RP3 | <<locked>> | 96% | 55,042 psi | 88% | 2644 fps | 100% |
| Bofors RP7ᴾ | <<locked>> | 100% | 55,680 psi | 89% | 2608 fps | 96.3% |
| Hodgdon Benchmark | <<locked>> | 88% | 55,608 psi | 89% | 2559 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 90% | 55,927 psi | 90% | 2648 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 86% | 54,056 psi | 87% | 2687 fps | 99.5% |
| Hodgdon H322 | <<locked>> | 86% | 53,388 psi | 86% | 2559 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 54,723 psi | 88% | 2589 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 56,318 psi | 90% | 2654 fps | 98.9% |
| Hodgdon H414 | <<locked>> | 98% | 53,287 psi | 85% | 2664 fps | 96.7% |
| Hodgdon H4895 | <<locked>> | 90% | 54,737 psi | 88% | 2625 fps | 99.9% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 43,627 psi | 70% | 2487 fps | 98.8% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 53,272 psi | 85% | 2651 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,983 psi | 56% | 1555 fps | 100% |
| Hodgdon VARGET | <<locked>> | 94% | 54,795 psi | 88% | 2608 fps | 99.9% |
| IMR 3031 | <<locked>> | 94% | 55,782 psi | 89% | 2631 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 53,664 psi | 86% | 2579 fps | 99.4% |
| IMR 4166 Enduron | <<locked>> | 96% | 53,592 psi | 86% | 2552 fps | 96.5% |
| IMR 4198 | <<locked>> | 84% | 55,347 psi | 89% | 2490 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 98% | 54,346 psi | 87% | 2592 fps | 96.6% |
| IMR 4831ᴾ | <<locked>> | 100% | 40,770 psi | 65% | 2451 fps | 96.8% |
| IMR 4895 | <<locked>> | 92% | 53,316 psi | 85% | 2631 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 88% | 53,548 psi | 86% | 2572 fps | 100% |
| Lovex D073.4 | <<locked>> | 84% | 56,086 psi | 90% | 2582 fps | 100% |
| Lovex D073.5 | <<locked>> | 84% | 53,592 psi | 86% | 2562 fps | 100% |
| Lovex D073.6 | <<locked>> | 90% | 53,519 psi | 86% | 2595 fps | 100% |
| Lovex S060 | <<locked>> | 90% | 54,418 psi | 87% | 2549 fps | 99.7% |
| Lovex S062 | <<locked>> | 94% | 54,215 psi | 87% | 2595 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 53,040 psi | 85% | 2582 fps | 97.8% |
| Lovex S070ᴾ | <<locked>> | 100% | 50,575 psi | 81% | 2566 fps | 96.2% |
| Norma 201 | <<locked>> | 92% | 56,391 psi | 90% | 2612 fps | 100% |
| Norma 202 | <<locked>> | 90% | 53,374 psi | 86% | 2569 fps | 100% |
| Norma 203B | <<locked>> | 94% | 54,534 psi | 87% | 2638 fps | 99.7% |
| Norma URPᴾ | <<locked>> | 100% | 47,964 psi | 77% | 2585 fps | 98.2% |
| Ramshot Big Game | <<locked>> | 94% | 54,955 psi | 88% | 2664 fps | 99.7% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 47,094 psi | 76% | 2572 fps | 96.2% |
| Ramshot TAC | <<locked>> | 88% | 54,027 psi | 87% | 2589 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 88% | 53,098 psi | 85% | 2605 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 86% | 54,592 psi | 88% | 2575 fps | 99.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,186 psi | 56% | 1591 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 84% | 53,330 psi | 86% | 2559 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 53,447 psi | 86% | 2589 fps | 97.2% |
| ReloadSwiss RS 52 | <<locked>> | 92% | 55,376 psi | 89% | 2710 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 98% | 55,013 psi | 88% | 2743 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 47,587 psi | 76% | 2608 fps | 97.9% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 48,573 psi | 78% | 2628 fps | 97.4% |
| Rottweil R 901 | <<locked>> | 88% | 54,172 psi | 87% | 2552 fps | 100% |
| Rottweil R 902 | <<locked>> | 92% | 53,374 psi | 86% | 2562 fps | 100% |
| Rottweil R 903 | <<locked>> | 98% | 54,650 psi | 88% | 2635 fps | 99.9% |
| Rottweil R 907ᴾ | <<locked>> | 100% | 55,680 psi | 89% | 2608 fps | 96.3% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 53,040 psi | 85% | 2582 fps | 97.8% |
| Shooters World Match Rifle | <<locked>> | 90% | 53,519 psi | 86% | 2595 fps | 100% |
| Shooters World Precision | <<locked>> | 94% | 54,215 psi | 87% | 2595 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 50,575 psi | 81% | 2566 fps | 96.2% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 52,852 psi | 85% | 2530 fps | 99.9% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 55,825 psi | 90% | 2598 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 96% | 52,895 psi | 85% | 2641 fps | 99.6% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 56,072 psi | 90% | 2549 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 55,666 psi | 89% | 2615 fps | 98.7% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 55,985 psi | 90% | 2635 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 90% | 55,230 psi | 89% | 2516 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 96% | 54,723 psi | 88% | 2510 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 53,650 psi | 86% | 2543 fps | 96.5% |
| Somchem S321 | <<locked>> | 86% | 54,665 psi | 88% | 2605 fps | 100% |
| Somchem S335 | <<locked>> | 90% | 54,070 psi | 87% | 2513 fps | 100% |
| Somchem S341 | <<locked>> | 90% | 54,984 psi | 88% | 2608 fps | 99.7% |
| Somchem S355 | <<locked>> | 98% | 55,259 psi | 89% | 2631 fps | 99.9% |
| Somchem S365ᴾ | <<locked>> | 100% | 42,699 psi | 68% | 2539 fps | 99.6% |
| Unknown powderᴾ | <<locked>> | 100% | 52,533 psi | 84% | 2644 fps | 98.3% |
| Vihtavuori N130 | <<locked>> | 86% | 54,940 psi | 88% | 2484 fps | 100% |
| Vihtavuori N133 | <<locked>> | 90% | 55,201 psi | 89% | 2503 fps | 100% |
| Vihtavuori N135 | <<locked>> | 94% | 56,028 psi | 90% | 2575 fps | 100% |
| Vihtavuori N140 | <<locked>> | 92% | 53,954 psi | 87% | 2552 fps | 100% |
| Vihtavuori N150 | <<locked>> | 98% | 53,359 psi | 86% | 2569 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 50,488 psi | 81% | 2585 fps | 98.4% |
| Vihtavuori N530 | <<locked>> | 88% | 54,027 psi | 87% | 2572 fps | 100% |
| Vihtavuori N540 | <<locked>> | 94% | 55,347 psi | 89% | 2592 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 49,429 psi | 79% | 2589 fps | 98.2% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 51,488 psi | 83% | 2575 fps | 99.8% |
| Winchester 748 | <<locked>> | 86% | 54,056 psi | 87% | 2628 fps | 100% |
| Winchester 760 | <<locked>> | 98% | 53,287 psi | 85% | 2664 fps | 96.7% |
| Winchester StaBALL Match | <<locked>> | 84% | 53,838 psi | 86% | 2618 fps | 99.9% |
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% | 43,221 psi | 69% | 2362 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 46,992 psi | 75% | 2457 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 35,723 psi | 57% | 2283 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 40,727 psi | 65% | 2402 fps | 99.8% |
| Accurate 2520 | <<locked>> | 80% | 40,727 psi | 65% | 2402 fps | 99.8% |
| Accurate 4064 | <<locked>> | 80% | 33,779 psi | 54% | 2270 fps | 99.4% |
| Accurate 4350 | <<locked>> | 92% | 36,463 psi | 58% | 2385 fps | 95.4% |
| Accurate LT-30 | <<locked>> | 80% | 51,503 psi | 83% | 2431 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 51,909 psi | 83% | 2454 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 39,639 psi | 64% | 2372 fps | 97.6% |
| ADI AR 2208 | <<locked>> | 80% | 33,866 psi | 54% | 2238 fps | 95% |
| ADI AR 2219 | <<locked>> | 80% | 51,996 psi | 83% | 2539 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 41,684 psi | 67% | 2385 fps | 99% |
| Alliant AR-Comp | <<locked>> | 80% | 41,089 psi | 66% | 2385 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 48,385 psi | 78% | 2566 fps | 99.5% |
| Alliant Power Pro 2000-MR | 63.6 gr | 80% | 35,752 psi | 57% | 2379 fps | 95.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 33,083 psi | 53% | 2257 fps | 96.7% |
| Alliant Reloder-10x | <<locked>> | 80% | 48,936 psi | 78% | 2451 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 35,549 psi | 57% | 2306 fps | 95.9% |
| Alliant Reloder-16 | <<locked>> | 92% | 37,304 psi | 60% | 2395 fps | 95.5% |
| Alliant Reloder-17 | <<locked>> | 84% | 32,489 psi | 52% | 2313 fps | 95.5% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 50,618 psi | 81% | 2434 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 38,609 psi | 62% | 2372 fps | 96.2% |
| Bofors RP3 | <<locked>> | 80% | 32,358 psi | 52% | 2254 fps | 96.6% |
| Bofors RP7 | <<locked>> | 98% | 52,228 psi | 84% | 2559 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 43,685 psi | 70% | 2379 fps | 99.5% |
| Hodgdon BL-C2 | <<locked>> | 80% | 39,900 psi | 64% | 2398 fps | 99.1% |
| Hodgdon CFE223 | <<locked>> | 80% | 43,801 psi | 70% | 2523 fps | 98.1% |
| Hodgdon H322 | <<locked>> | 80% | 44,237 psi | 71% | 2428 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 51,213 psi | 82% | 2543 fps | 100% |
| Hodgdon H380 | <<locked>> | 84% | 38,130 psi | 61% | 2356 fps | 95.2% |
| Hodgdon H414 | <<locked>> | 94% | 46,485 psi | 75% | 2559 fps | 95.1% |
| Hodgdon H4895 | <<locked>> | 80% | 39,972 psi | 64% | 2382 fps | 98.2% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 32,039 psi | 51% | 2251 fps | 95.5% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 33,823 psi | 54% | 2303 fps | 97% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,904 psi | 42% | 1385 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 35,723 psi | 57% | 2283 fps | 97% |
| IMR 3031 | <<locked>> | 80% | 35,810 psi | 57% | 2326 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 33,141 psi | 53% | 2215 fps | 95% |
| IMR 4166 Enduron | <<locked>> | 92% | 47,790 psi | 77% | 2461 fps | 95.2% |
| IMR 4198 | <<locked>> | 80% | 49,443 psi | 79% | 2415 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 94% | 48,240 psi | 77% | 2500 fps | 95.3% |
| IMR 4831 | <<locked>> | 96% | 35,940 psi | 58% | 2356 fps | 95.2% |
| IMR 4895 | <<locked>> | 80% | 36,376 psi | 58% | 2336 fps | 96.8% |
| IMR 8208 XBR | <<locked>> | 80% | 41,684 psi | 67% | 2385 fps | 99% |
| Lovex D073.4 | <<locked>> | 80% | 48,921 psi | 78% | 2487 fps | 100% |
| Lovex D073.5 | <<locked>> | 80% | 46,804 psi | 75% | 2464 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 38,290 psi | 61% | 2359 fps | 99.5% |
| Lovex S060 | <<locked>> | 80% | 40,306 psi | 65% | 2320 fps | 97.7% |
| Lovex S062 | <<locked>> | 80% | 35,230 psi | 56% | 2274 fps | 97.7% |
| Lovex S065 | <<locked>> | 92% | 41,684 psi | 67% | 2395 fps | 95.2% |
| Lovex S070 | <<locked>> | 98% | 47,500 psi | 76% | 2516 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 38,914 psi | 62% | 2333 fps | 98.6% |
| Norma 202 | <<locked>> | 80% | 39,117 psi | 63% | 2346 fps | 99.8% |
| Norma 203B | <<locked>> | 80% | 34,940 psi | 56% | 2297 fps | 96.3% |
| Norma URP | <<locked>> | 92% | 37,188 psi | 60% | 2388 fps | 95.4% |
| Ramshot Big Game | <<locked>> | 80% | 34,301 psi | 55% | 2303 fps | 95.7% |
| Ramshot Hunter | <<locked>> | 98% | 44,251 psi | 71% | 2526 fps | 95.4% |
| Ramshot TAC | <<locked>> | 80% | 41,568 psi | 67% | 2382 fps | 95.4% |
| Ramshot Wild Boar | <<locked>> | 80% | 40,727 psi | 65% | 2402 fps | 97.8% |
| Ramshot X-Terminator | <<locked>> | 80% | 45,194 psi | 72% | 2431 fps | 98.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,165 psi | 42% | 1421 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 46,775 psi | 75% | 2464 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 44,135 psi | 71% | 2441 fps | 95.1% |
| ReloadSwiss RS 52 | 61.7 gr | 80% | 36,767 psi | 59% | 2395 fps | 96.2% |
| ReloadSwiss RS 60 | 62.7 gr | 80% | 30,443 psi | 49% | 2267 fps | 97.3% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 38,914 psi | 62% | 2451 fps | 95.7% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 42,627 psi | 68% | 2520 fps | 95.8% |
| Rottweil R 901 | <<locked>> | 80% | 42,917 psi | 69% | 2382 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 37,115 psi | 60% | 2290 fps | 98.2% |
| Rottweil R 903 | <<locked>> | 80% | 30,443 psi | 49% | 2201 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 98% | 52,228 psi | 84% | 2559 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 92% | 41,684 psi | 67% | 2395 fps | 95.2% |
| Shooters World Match Rifle | <<locked>> | 80% | 38,290 psi | 61% | 2359 fps | 99.5% |
| Shooters World Precision | <<locked>> | 80% | 35,230 psi | 56% | 2274 fps | 97.7% |
| Shooters World SW4350 | <<locked>> | 98% | 47,500 psi | 76% | 2516 fps | 95.5% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 49,385 psi | 79% | 2480 fps | 99.7% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 52,286 psi | 84% | 2552 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 33,649 psi | 54% | 2293 fps | 95.6% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 49,661 psi | 80% | 2467 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 39,624 psi | 64% | 2356 fps | 95.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 38,232 psi | 61% | 2343 fps | 97.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 40,596 psi | 65% | 2300 fps | 99.9% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 33,431 psi | 54% | 2178 fps | 99.6% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 46,876 psi | 75% | 2441 fps | 95% |
| Somchem S321 | <<locked>> | 80% | 44,817 psi | 72% | 2457 fps | 99.6% |
| Somchem S335 | <<locked>> | 80% | 40,016 psi | 64% | 2303 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 39,349 psi | 63% | 2359 fps | 97.4% |
| Somchem S355 | <<locked>> | 80% | 31,488 psi | 50% | 2211 fps | 95.6% |
| Somchem S365 | <<locked>> | 88% | 29,283 psi | 47% | 2241 fps | 95.9% |
| Unknown powder | <<locked>> | 92% | 40,669 psi | 65% | 2444 fps | 95.7% |
| Vihtavuori N130 | <<locked>> | 80% | 45,963 psi | 74% | 2365 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 40,756 psi | 65% | 2300 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 36,129 psi | 58% | 2283 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 36,941 psi | 59% | 2290 fps | 99.8% |
| Vihtavuori N150 | <<locked>> | 80% | 29,892 psi | 48% | 2156 fps | 96.5% |
| Vihtavuori N160 | <<locked>> | 90% | 36,579 psi | 59% | 2339 fps | 95% |
| Vihtavuori N530 | <<locked>> | 80% | 41,713 psi | 67% | 2382 fps | 99.1% |
| Vihtavuori N540 | <<locked>> | 80% | 35,433 psi | 57% | 2274 fps | 99.4% |
| Vihtavuori N550 | <<locked>> | 92% | 38,159 psi | 61% | 2392 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 32,518 psi | 52% | 2228 fps | 95.7% |
| Winchester 748 | <<locked>> | 80% | 43,976 psi | 71% | 2477 fps | 99.8% |
| Winchester 760 | <<locked>> | 94% | 46,485 psi | 75% | 2559 fps | 95.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 46,702 psi | 75% | 2513 fps | 99.3% |
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 H&H Mag. loaded with the .375 | 270gr | Swift A-Frame. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,743 fps; across all powders the maximum-charge window runs from 1,555 fps to 2,743 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 (430 MPa), the top charges use 56–90 %, 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-17 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, ReloadSwiss RS 52 rank at the top here: for .375 H&H 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.