Load Specifications
Bullet:.375 | 270gr | Atomic 29 HP
Bullet Manufacturer:Atomic 29
Bullet Weight:270 gr
Bullet Diameter:0.375"
Bullet Length:<<locked>>
Caliber:.375 Rem. Ultra Mag. load data
Case Length (l3):2.85"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:117 Grains of Water
Primer Size:Large Rifle Magnum (LRM)
Barrel Length:24"
Max. allowed Pressure:63,817 psi
Recommended Twist Rate:1:17.0
Load data in caliber .375 Rem. Ultra Mag. with .375 | 270gr | Atomic 29 HP bullet and 103 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Hodgdon Superformance 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>> | 82% | 54,723 psi | 86% | 2546 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 57,159 psi | 90% | 2612 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 55,288 psi | 87% | 2631 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 56,347 psi | 88% | 2631 fps | 98.3% |
| Accurate 3100ᴾ | <<locked>> | 100% | 44,454 psi | 70% | 2539 fps | 97.9% |
| Accurate 4064 | <<locked>> | 90% | 57,174 psi | 90% | 2657 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 54,070 psi | 85% | 2703 fps | 99.9% |
| ADI AR 2206H | <<locked>> | 86% | 57,551 psi | 90% | 2697 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 55,172 psi | 86% | 2651 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 52,388 psi | 82% | 2687 fps | 96.9% |
| ADI Benchmark 8208 | <<locked>> | 84% | 56,420 psi | 88% | 2648 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 57,725 psi | 90% | 2615 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 54,085 psi | 85% | 2762 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 55,448 psi | 87% | 2671 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 55,883 psi | 88% | 2690 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 98% | 55,332 psi | 87% | 2759 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 94% | 56,927 psi | 89% | 2789 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 51,358 psi | 80% | 2674 fps | 96.9% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 42,308 psi | 66% | 2569 fps | 99.8% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 37,057 psi | 58% | 2470 fps | 96.3% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 47,877 psi | 75% | 2733 fps | 99.6% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 57,725 psi | 90% | 2713 fps | 100% |
| Bofors RP3 | <<locked>> | 90% | 56,086 psi | 88% | 2684 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 55,869 psi | 88% | 2664 fps | 98.4% |
| Hodgdon Benchmark | <<locked>> | 82% | 54,375 psi | 85% | 2582 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 56,014 psi | 88% | 2674 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 56,971 psi | 89% | 2700 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 96% | 57,116 psi | 90% | 2756 fps | 99.1% |
| Hodgdon H4350 | <<locked>> | 94% | 57,319 psi | 90% | 2717 fps | 98.1% |
| Hodgdon H4895 | <<locked>> | 84% | 54,607 psi | 86% | 2657 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 55,390 psi | 87% | 2684 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 54,288 psi | 85% | 2687 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 53,708 psi | 84% | 2736 fps | 98.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,578 psi | 56% | 1637 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 55,767 psi | 87% | 2657 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 54,752 psi | 86% | 2638 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 54,694 psi | 86% | 2638 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 54,273 psi | 85% | 2615 fps | 98.6% |
| IMR 4350 | <<locked>> | 98% | 56,507 psi | 89% | 2687 fps | 98.5% |
| IMR 4451 Enduron | <<locked>> | 92% | 54,418 psi | 85% | 2644 fps | 98.6% |
| IMR 4831 | <<locked>> | 98% | 54,839 psi | 86% | 2697 fps | 100% |
| IMR 4895 | <<locked>> | 88% | 57,290 psi | 90% | 2720 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 56,420 psi | 88% | 2648 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 57,711 psi | 90% | 2671 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 56,811 psi | 89% | 2628 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 54,389 psi | 85% | 2628 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 57,276 psi | 90% | 2684 fps | 99.7% |
| Lovex S070 | <<locked>> | 96% | 54,940 psi | 86% | 2671 fps | 98.9% |
| Norma 201 | <<locked>> | 86% | 56,043 psi | 88% | 2641 fps | 100% |
| Norma 202 | <<locked>> | 86% | 56,753 psi | 89% | 2641 fps | 100% |
| Norma 203B | <<locked>> | 88% | 55,085 psi | 86% | 2680 fps | 100% |
| Norma 204 | <<locked>> | 98% | 57,508 psi | 90% | 2740 fps | 97.7% |
| Norma MRPᴾ | <<locked>> | 100% | 47,616 psi | 75% | 2690 fps | 97.7% |
| Norma URP | <<locked>> | 98% | 56,927 psi | 89% | 2743 fps | 100% |
| Ramshot Big Game | <<locked>> | 88% | 55,985 psi | 88% | 2703 fps | 100% |
| Ramshot Hunter | <<locked>> | 98% | 55,709 psi | 87% | 2743 fps | 99.4% |
| Ramshot TAC | <<locked>> | 84% | 56,666 psi | 89% | 2671 fps | 99.7% |
| Ramshot Wild Boar | <<locked>> | 84% | 56,594 psi | 89% | 2687 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 57,232 psi | 90% | 2651 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,100 psi | 57% | 1677 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 57,232 psi | 90% | 2684 fps | 99.3% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 56,652 psi | 89% | 2756 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 56,536 psi | 89% | 2785 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 54,128 psi | 85% | 2726 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 57,217 psi | 90% | 2808 fps | 100% |
| Rottweil R 901 | <<locked>> | 84% | 56,739 psi | 89% | 2618 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 56,492 psi | 89% | 2638 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 55,898 psi | 88% | 2677 fps | 100% |
| Rottweil R 904ᴾ | <<locked>> | 100% | 54,331 psi | 85% | 2664 fps | 96.1% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 50,082 psi | 78% | 2657 fps | 96.8% |
| Rottweil R 907 | <<locked>> | 94% | 55,869 psi | 88% | 2664 fps | 98.4% |
| Shooters World Long Rifle | <<locked>> | 96% | 57,276 psi | 90% | 2684 fps | 99.7% |
| Shooters World Match Rifle | <<locked>> | 86% | 57,711 psi | 90% | 2671 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 54,389 psi | 85% | 2628 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 54,940 psi | 86% | 2671 fps | 98.9% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 54,389 psi | 85% | 2690 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 55,187 psi | 86% | 2648 fps | 99.8% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 55,970 psi | 88% | 2671 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 57,537 psi | 90% | 2582 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 54,607 psi | 86% | 2536 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 57,667 psi | 90% | 2641 fps | 99% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 49,603 psi | 78% | 2651 fps | 96.6% |
| Somchem S321 | <<locked>> | 82% | 57,740 psi | 90% | 2677 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 56,826 psi | 89% | 2575 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 55,013 psi | 86% | 2641 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 56,130 psi | 88% | 2674 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 55,201 psi | 87% | 2740 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 50,865 psi | 80% | 2638 fps | 97.7% |
| Vihtavuori N130 | <<locked>> | 82% | 56,956 psi | 89% | 2539 fps | 100% |
| Vihtavuori N133 | <<locked>> | 84% | 54,520 psi | 85% | 2523 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 56,695 psi | 89% | 2602 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 57,392 psi | 90% | 2618 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 54,114 psi | 85% | 2608 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 55,637 psi | 87% | 2687 fps | 99.9% |
| Vihtavuori N530 | <<locked>> | 84% | 56,927 psi | 89% | 2648 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 55,521 psi | 87% | 2618 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 54,650 psi | 86% | 2694 fps | 99.9% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 46,934 psi | 74% | 2638 fps | 99.8% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 55,854 psi | 88% | 2664 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 57,246 psi | 90% | 2690 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 57,334 psi | 90% | 2759 fps | 99.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 37,884 psi | 59% | 2592 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 86% | 56,057 psi | 88% | 2677 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% | 51,242 psi | 80% | 2503 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 43,714 psi | 69% | 2438 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 51,561 psi | 81% | 2585 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 43,033 psi | 67% | 2425 fps | 95.5% |
| Accurate 3100 | <<locked>> | 94% | 35,984 psi | 56% | 2382 fps | 95.5% |
| Accurate 4064 | <<locked>> | 80% | 41,365 psi | 65% | 2438 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 30,632 psi | 48% | 2280 fps | 95.3% |
| ADI AR 2206H | <<locked>> | 80% | 47,543 psi | 75% | 2552 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 80% | 40,248 psi | 63% | 2411 fps | 98.7% |
| ADI AR 2209 | <<locked>> | 96% | 45,861 psi | 72% | 2579 fps | 95.2% |
| ADI Benchmark 8208 | <<locked>> | 80% | 49,676 psi | 78% | 2556 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 50,517 psi | 79% | 2530 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 43,656 psi | 68% | 2595 fps | 99.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 40,132 psi | 63% | 2434 fps | 99.6% |
| Alliant Reloder-15 | <<locked>> | 80% | 43,105 psi | 68% | 2497 fps | 99.3% |
| Alliant Reloder-16 | <<locked>> | 80% | 31,067 psi | 49% | 2297 fps | 95.5% |
| Alliant Reloder-17 | 75.8 gr | 80% | 34,751 psi | 54% | 2415 fps | 98.6% |
| Alliant Reloder-19 | <<locked>> | 96% | 45,092 psi | 71% | 2569 fps | 95.3% |
| Alliant Reloder-23 | <<locked>> | 86% | 26,948 psi | 42% | 2211 fps | 95.2% |
| Alliant Reloder-25 | <<locked>> | 98% | 34,751 psi | 54% | 2418 fps | 95.3% |
| Alliant Reloder-26 | <<locked>> | 90% | 33,199 psi | 52% | 2431 fps | 95.8% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 47,079 psi | 74% | 2562 fps | 99.5% |
| Bofors RP3 | <<locked>> | 80% | 39,914 psi | 63% | 2438 fps | 99.6% |
| Bofors RP7 | <<locked>> | 84% | 40,698 psi | 64% | 2415 fps | 95.1% |
| Hodgdon Benchmark | <<locked>> | 80% | 51,227 psi | 80% | 2539 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 48,878 psi | 77% | 2579 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 40,567 psi | 64% | 2441 fps | 97.9% |
| Hodgdon H414 | <<locked>> | 84% | 37,985 psi | 60% | 2438 fps | 95% |
| Hodgdon H4350 | <<locked>> | 86% | 44,193 psi | 69% | 2513 fps | 95.3% |
| Hodgdon H4895 | <<locked>> | 80% | 48,008 psi | 75% | 2562 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 28,398 psi | 45% | 2205 fps | 96.3% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 44,266 psi | 69% | 2539 fps | 100% |
| Hodgdon Superformance | 86.1 gr | 86% | 40,074 psi | 63% | 2500 fps | 95.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,571 psi | 42% | 1467 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 45,977 psi | 72% | 2516 fps | 99.9% |
| IMR 3031 | <<locked>> | 80% | 47,921 psi | 75% | 2546 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 42,293 psi | 66% | 2444 fps | 99.2% |
| IMR 4166 Enduron | <<locked>> | 80% | 44,860 psi | 70% | 2467 fps | 96.8% |
| IMR 4350 | <<locked>> | 88% | 41,162 psi | 65% | 2444 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 82% | 39,784 psi | 62% | 2398 fps | 95.3% |
| IMR 4831 | <<locked>> | 80% | 29,820 psi | 47% | 2244 fps | 95% |
| IMR 4895 | <<locked>> | 80% | 44,208 psi | 69% | 2523 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 80% | 49,676 psi | 78% | 2556 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 46,949 psi | 74% | 2530 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 47,181 psi | 74% | 2490 fps | 99.9% |
| Lovex S062 | <<locked>> | 80% | 42,235 psi | 66% | 2444 fps | 99.9% |
| Lovex S065 | <<locked>> | 80% | 34,635 psi | 54% | 2300 fps | 95.2% |
| Lovex S070 | <<locked>> | 84% | 37,420 psi | 59% | 2375 fps | 95% |
| Norma 201 | <<locked>> | 80% | 46,296 psi | 73% | 2503 fps | 100% |
| Norma 202 | <<locked>> | 80% | 46,876 psi | 73% | 2507 fps | 100% |
| Norma 203B | <<locked>> | 80% | 42,467 psi | 67% | 2484 fps | 99.5% |
| Norma 204 | <<locked>> | 92% | 46,731 psi | 73% | 2579 fps | 95.5% |
| Norma MRP | <<locked>> | 96% | 41,350 psi | 65% | 2572 fps | 95.9% |
| Norma URP | <<locked>> | 80% | 31,082 psi | 49% | 2287 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 80% | 42,337 psi | 66% | 2500 fps | 99.4% |
| Ramshot Hunter | <<locked>> | 86% | 37,130 psi | 58% | 2428 fps | 95.7% |
| Ramshot TAC | <<locked>> | 80% | 49,574 psi | 78% | 2569 fps | 99% |
| Ramshot Wild Boar | <<locked>> | 80% | 49,313 psi | 77% | 2585 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 80% | 53,447 psi | 84% | 2598 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,818 psi | 42% | 1499 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 41,046 psi | 64% | 2431 fps | 96.5% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 45,876 psi | 72% | 2595 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 37,028 psi | 58% | 2474 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 82% | 32,721 psi | 51% | 2349 fps | 95.8% |
| ReloadSwiss RS 70 | 80.8 gr | 84% | 34,998 psi | 55% | 2411 fps | 95.9% |
| Rottweil R 901 | <<locked>> | 80% | 50,270 psi | 79% | 2533 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 44,077 psi | 69% | 2461 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 37,463 psi | 59% | 2388 fps | 99.2% |
| Rottweil R 904 | <<locked>> | 98% | 50,850 psi | 80% | 2612 fps | 95.3% |
| Rottweil R 905 | <<locked>> | 96% | 43,874 psi | 69% | 2552 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 84% | 40,698 psi | 64% | 2415 fps | 95.1% |
| Shooters World Long Rifle | <<locked>> | 80% | 34,635 psi | 54% | 2300 fps | 95.2% |
| Shooters World Match Rifle | <<locked>> | 80% | 46,949 psi | 74% | 2530 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 42,235 psi | 66% | 2444 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 84% | 37,420 psi | 59% | 2375 fps | 95% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 38,624 psi | 61% | 2434 fps | 98.8% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 47,935 psi | 75% | 2543 fps | 99.1% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 45,977 psi | 72% | 2523 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 47,558 psi | 75% | 2451 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 39,726 psi | 62% | 2329 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 38,653 psi | 61% | 2343 fps | 95.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 43,468 psi | 68% | 2549 fps | 95% |
| Somchem S321 | <<locked>> | 80% | 54,012 psi | 85% | 2628 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 47,224 psi | 74% | 2451 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 47,906 psi | 75% | 2539 fps | 99.9% |
| Somchem S355 | <<locked>> | 80% | 38,174 psi | 60% | 2392 fps | 99.1% |
| Somchem S365 | <<locked>> | 80% | 27,775 psi | 44% | 2241 fps | 97.5% |
| Somchem S385 | <<locked>> | 94% | 41,510 psi | 65% | 2480 fps | 95.4% |
| Vihtavuori N130 | <<locked>> | 80% | 53,577 psi | 84% | 2500 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 48,037 psi | 75% | 2441 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 43,801 psi | 69% | 2434 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 44,454 psi | 70% | 2444 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 36,390 psi | 57% | 2333 fps | 99.6% |
| Vihtavuori N160 | <<locked>> | 80% | 32,474 psi | 51% | 2290 fps | 95.8% |
| Vihtavuori N530 | <<locked>> | 80% | 49,922 psi | 78% | 2552 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 42,728 psi | 67% | 2438 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 31,894 psi | 50% | 2287 fps | 95.3% |
| Vihtavuori N555 | <<locked>> | 86% | 29,066 psi | 46% | 2280 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 32,227 psi | 51% | 2267 fps | 98% |
| Winchester 748 | <<locked>> | 80% | 49,879 psi | 78% | 2595 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 37,985 psi | 60% | 2438 fps | 95% |
| Winchester StaBALL HD | <<locked>> | 90% | 27,050 psi | 42% | 2283 fps | 95.9% |
| Winchester StaBALL Match | <<locked>> | 80% | 45,672 psi | 72% | 2530 fps | 99.9% |
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 103 powders for .375 Rem. Ultra Mag. loaded with the .375 | 270gr | Atomic 29 HP. ReloadSwiss RS 70 delivers the highest muzzle velocity at 2,808 fps; across all powders the maximum-charge window runs from 1,637 fps to 2,808 fps. Accurate 3100 gives the best case fill at 100 %, and 103 of the 103 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 270.0 gr projectile in 0.375" calls for a 1:17.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, Alliant Reloder-19 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 70, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for .375 Rem. Ultra Mag. with the .375 | 270gr | Atomic 29 HP 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.