Load Specifications
Load data in caliber .375 Ruger with .375 | 240gr | Atomic 29 HP bullet and 94 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 52 and Hodgdon LEVERevolution.
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.
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You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 23"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 90% | 55,695 psi | 90% | 2635 fps | 100% |
| Accurate 2200 | <<locked>> | 82% | 56,057 psi | 90% | 2726 fps | 99% |
| Accurate 2460 | <<locked>> | 86% | 54,070 psi | 87% | 2654 fps | 100% |
| Accurate 2495 | <<locked>> | 96% | 56,173 psi | 90% | 2684 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 55,999 psi | 90% | 2710 fps | 100% |
| Accurate 4064 | <<locked>> | 98% | 55,811 psi | 90% | 2720 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 44,773 psi | 72% | 2618 fps | 96.8% |
| Accurate LT-30 | <<locked>> | 84% | 55,840 psi | 90% | 2589 fps | 100% |
| Accurate LT-32 | <<locked>> | 82% | 52,881 psi | 85% | 2569 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 54,737 psi | 88% | 2713 fps | 99.4% |
| ADI AR 2208 | <<locked>> | 98% | 56,014 psi | 90% | 2710 fps | 99.1% |
| ADI AR 2219 | <<locked>> | 82% | 52,765 psi | 85% | 2654 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 54,244 psi | 87% | 2677 fps | 99.8% |
| Alliant AR-Comp | <<locked>> | 90% | 53,722 psi | 87% | 2661 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 55,651 psi | 90% | 2776 fps | 99.7% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 54,433 psi | 88% | 2815 fps | 98.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 98% | 55,129 psi | 89% | 2730 fps | 99.8% |
| Alliant Reloder-10x | <<locked>> | 86% | 55,434 psi | 89% | 2641 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 55,883 psi | 90% | 2746 fps | 99.2% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 45,063 psi | 73% | 2631 fps | 96.9% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 52,272 psi | 84% | 2779 fps | 99.6% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 54,955 psi | 89% | 2582 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 54,926 psi | 88% | 2726 fps | 98.7% |
| Bofors RP3 | <<locked>> | 98% | 55,376 psi | 89% | 2740 fps | 99.8% |
| Hodgdon Benchmark | <<locked>> | 88% | 53,069 psi | 85% | 2618 fps | 99.9% |
| Hodgdon BL-C2 | <<locked>> | 90% | 52,881 psi | 85% | 2697 fps | 99.9% |
| Hodgdon CFE223 | <<locked>> | 88% | 54,911 psi | 88% | 2789 fps | 99.1% |
| Hodgdon H322 | <<locked>> | 86% | 54,882 psi | 88% | 2680 fps | 100% |
| Hodgdon H335 | <<locked>> | 84% | 52,446 psi | 84% | 2657 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 53,563 psi | 86% | 2700 fps | 97.9% |
| Hodgdon H4895 | <<locked>> | 92% | 55,259 psi | 89% | 2726 fps | 99.7% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 41,104 psi | 66% | 2520 fps | 97.5% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 54,041 psi | 87% | 2749 fps | 99.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,403 psi | 55% | 1637 fps | 100% |
| Hodgdon VARGET | <<locked>> | 92% | 53,476 psi | 86% | 2680 fps | 99.5% |
| IMR 3031 | <<locked>> | 92% | 54,621 psi | 88% | 2717 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 55,434 psi | 89% | 2694 fps | 99.1% |
| IMR 4198 | <<locked>> | 86% | 55,999 psi | 90% | 2608 fps | 100% |
| IMR 4451 Enduronᴾ | <<locked>> | 100% | 55,245 psi | 89% | 2684 fps | 95.9% |
| IMR 4831ᴾ | <<locked>> | 100% | 42,931 psi | 69% | 2569 fps | 96.4% |
| IMR 4895 | <<locked>> | 94% | 53,795 psi | 87% | 2730 fps | 99.4% |
| IMR 8208 XBR | <<locked>> | 90% | 54,244 psi | 87% | 2677 fps | 99.8% |
| Lovex D073.5 | <<locked>> | 86% | 54,288 psi | 87% | 2664 fps | 100% |
| Lovex D073.6 | <<locked>> | 92% | 53,751 psi | 87% | 2690 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 55,172 psi | 89% | 2651 fps | 99.4% |
| Lovex S062 | <<locked>> | 96% | 54,491 psi | 88% | 2690 fps | 99.9% |
| Lovex S065ᴾ | <<locked>> | 100% | 50,488 psi | 81% | 2625 fps | 96.5% |
| Norma 200 | <<locked>> | 82% | 55,129 psi | 89% | 2615 fps | 100% |
| Norma 201 | <<locked>> | 92% | 53,359 psi | 86% | 2664 fps | 99.8% |
| Norma 202 | <<locked>> | 92% | 53,882 psi | 87% | 2674 fps | 100% |
| Norma 203B | <<locked>> | 96% | 54,955 psi | 89% | 2733 fps | 99.4% |
| Norma URPᴾ | <<locked>> | 100% | 45,136 psi | 73% | 2618 fps | 96.7% |
| Ramshot Big Game | <<locked>> | 96% | 55,811 psi | 90% | 2759 fps | 99.4% |
| Ramshot TAC | <<locked>> | 90% | 54,868 psi | 88% | 2684 fps | 97.5% |
| Ramshot Wild Boar | <<locked>> | 90% | 54,070 psi | 87% | 2707 fps | 99.3% |
| Ramshot X-Terminator | <<locked>> | 88% | 55,622 psi | 90% | 2677 fps | 99.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,621 psi | 56% | 1677 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 53,925 psi | 87% | 2664 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 54,244 psi | 87% | 2680 fps | 96.5% |
| ReloadSwiss RS 52 | <<locked>> | 94% | 56,159 psi | 90% | 2812 fps | 99.2% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 55,912 psi | 90% | 2841 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 44,817 psi | 72% | 2635 fps | 96.4% |
| Rottweil R 901 | <<locked>> | 90% | 54,157 psi | 87% | 2654 fps | 100% |
| Rottweil R 902 | <<locked>> | 94% | 53,751 psi | 87% | 2661 fps | 99.8% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 54,998 psi | 89% | 2726 fps | 99.7% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 50,488 psi | 81% | 2625 fps | 96.5% |
| Shooters World Match Rifle | <<locked>> | 92% | 53,751 psi | 87% | 2690 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 54,491 psi | 88% | 2690 fps | 99.9% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 53,896 psi | 87% | 2635 fps | 99.7% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 55,811 psi | 90% | 2359 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 53,185 psi | 86% | 2661 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 53,780 psi | 87% | 2740 fps | 99.3% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 53,185 psi | 86% | 2618 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 52,823 psi | 85% | 2657 fps | 97.7% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 53,403 psi | 86% | 2687 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 55,840 psi | 90% | 2621 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 55,535 psi | 89% | 2615 fps | 100% |
| Somchem S321 | <<locked>> | 88% | 55,463 psi | 89% | 2710 fps | 99.9% |
| Somchem S335 | <<locked>> | 92% | 54,665 psi | 88% | 2615 fps | 100% |
| Somchem S341 | <<locked>> | 92% | 56,173 psi | 90% | 2707 fps | 99.4% |
| Somchem S355ᴾ | <<locked>> | 100% | 55,782 psi | 90% | 2726 fps | 99.7% |
| Somchem S365ᴾ | <<locked>> | 100% | 40,001 psi | 64% | 2566 fps | 98.7% |
| Vihtavuori N130 | <<locked>> | 88% | 55,651 psi | 90% | 2595 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 55,767 psi | 90% | 2608 fps | 100% |
| Vihtavuori N135 | <<locked>> | 94% | 52,750 psi | 85% | 2635 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 54,491 psi | 88% | 2651 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 53,940 psi | 87% | 2664 fps | 99.9% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 47,630 psi | 77% | 2621 fps | 97.2% |
| Vihtavuori N530 | <<locked>> | 90% | 54,926 psi | 88% | 2677 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 94% | 52,707 psi | 85% | 2648 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 46,630 psi | 75% | 2621 fps | 96.8% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 49,066 psi | 79% | 2612 fps | 99.1% |
| Winchester 748 | <<locked>> | 90% | 54,099 psi | 87% | 2720 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 92% | 52,939 psi | 85% | 2694 fps | 99.5% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 23"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 40,495 psi | 65% | 2418 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 52,330 psi | 84% | 2671 fps | 98.5% |
| Accurate 2460 | <<locked>> | 80% | 44,121 psi | 71% | 2510 fps | 99.8% |
| Accurate 2495 | <<locked>> | 80% | 32,503 psi | 52% | 2316 fps | 99.9% |
| Accurate 2520 | <<locked>> | 80% | 39,233 psi | 63% | 2457 fps | 99.2% |
| Accurate 4064 | <<locked>> | 80% | 30,777 psi | 50% | 2297 fps | 98.1% |
| Accurate 4350 | <<locked>> | 96% | 38,667 psi | 62% | 2507 fps | 95% |
| Accurate LT-30 | <<locked>> | 80% | 49,298 psi | 79% | 2503 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 49,661 psi | 80% | 2523 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 37,260 psi | 60% | 2411 fps | 95.9% |
| ADI AR 2208 | <<locked>> | 86% | 38,493 psi | 62% | 2421 fps | 95.5% |
| ADI AR 2219 | <<locked>> | 80% | 49,269 psi | 79% | 2605 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 39,349 psi | 63% | 2434 fps | 97.8% |
| Alliant AR-Comp | <<locked>> | 80% | 38,232 psi | 62% | 2441 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 45,513 psi | 73% | 2618 fps | 98.6% |
| Alliant Power Pro 2000-MR | 69.2 gr | 84% | 38,551 psi | 62% | 2523 fps | 95% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 32,721 psi | 53% | 2333 fps | 95.5% |
| Alliant Reloder-10x | <<locked>> | 80% | 46,079 psi | 74% | 2516 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 37,927 psi | 61% | 2444 fps | 95.6% |
| Alliant Reloder-16 | <<locked>> | 96% | 39,798 psi | 64% | 2523 fps | 95.2% |
| Alliant Reloder-17 | <<locked>> | 88% | 34,751 psi | 56% | 2444 fps | 95.3% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 48,298 psi | 78% | 2493 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 38,769 psi | 62% | 2457 fps | 95.1% |
| Bofors RP3 | <<locked>> | 82% | 31,850 psi | 51% | 2326 fps | 95.3% |
| Hodgdon Benchmark | <<locked>> | 80% | 41,365 psi | 67% | 2434 fps | 98.7% |
| Hodgdon BL-C2 | <<locked>> | 80% | 37,318 psi | 60% | 2438 fps | 97.9% |
| Hodgdon CFE223 | <<locked>> | 80% | 41,249 psi | 66% | 2562 fps | 96.6% |
| Hodgdon H322 | <<locked>> | 80% | 44,918 psi | 72% | 2539 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 45,672 psi | 74% | 2556 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 43,598 psi | 70% | 2539 fps | 95.8% |
| Hodgdon H4895 | <<locked>> | 80% | 37,550 psi | 60% | 2425 fps | 96.7% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 33,881 psi | 55% | 2369 fps | 95.1% |
| Hodgdon LEVERevolution | 64.6 gr | 80% | 33,460 psi | 54% | 2379 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,295 psi | 41% | 1460 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 36,260 psi | 58% | 2382 fps | 96.2% |
| IMR 3031 | <<locked>> | 80% | 36,332 psi | 59% | 2434 fps | 99.9% |
| IMR 4064 | <<locked>> | 84% | 37,869 psi | 61% | 2402 fps | 95.6% |
| IMR 4198 | <<locked>> | 80% | 46,934 psi | 76% | 2487 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 98% | 51,982 psi | 84% | 2638 fps | 95.1% |
| IMR 4831 | <<locked>> | 98% | 40,190 psi | 65% | 2516 fps | 95.6% |
| IMR 4895 | <<locked>> | 82% | 36,216 psi | 58% | 2421 fps | 95.7% |
| IMR 8208 XBR | <<locked>> | 80% | 39,349 psi | 63% | 2434 fps | 97.8% |
| Lovex D073.5 | <<locked>> | 80% | 43,888 psi | 71% | 2510 fps | 99.3% |
| Lovex D073.6 | <<locked>> | 80% | 35,462 psi | 57% | 2392 fps | 98.4% |
| Lovex S060 | <<locked>> | 80% | 38,116 psi | 61% | 2369 fps | 96.2% |
| Lovex S062 | <<locked>> | 80% | 32,750 psi | 53% | 2306 fps | 96% |
| Lovex S065 | <<locked>> | 96% | 44,411 psi | 72% | 2526 fps | 95% |
| Norma 200 | <<locked>> | 80% | 51,764 psi | 83% | 2572 fps | 100% |
| Norma 201 | <<locked>> | 80% | 36,318 psi | 59% | 2372 fps | 97.1% |
| Norma 202 | <<locked>> | 80% | 36,564 psi | 59% | 2392 fps | 99.1% |
| Norma 203B | <<locked>> | 82% | 34,751 psi | 56% | 2382 fps | 95.1% |
| Norma URP | <<locked>> | 96% | 39,494 psi | 64% | 2513 fps | 95.1% |
| Ramshot Big Game | <<locked>> | 84% | 36,854 psi | 59% | 2441 fps | 95.6% |
| Ramshot TAC | <<locked>> | 84% | 44,875 psi | 72% | 2526 fps | 95.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 38,276 psi | 62% | 2441 fps | 96.2% |
| Ramshot X-Terminator | <<locked>> | 80% | 42,641 psi | 69% | 2474 fps | 97.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,599 psi | 41% | 1499 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 44,295 psi | 71% | 2520 fps | 99.6% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 47,514 psi | 77% | 2579 fps | 95% |
| ReloadSwiss RS 52 | 65.5 gr | 82% | 36,651 psi | 59% | 2477 fps | 95% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 30,284 psi | 49% | 2339 fps | 95.9% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 41,858 psi | 67% | 2582 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 39,929 psi | 64% | 2428 fps | 99.4% |
| Rottweil R 902 | <<locked>> | 80% | 34,432 psi | 55% | 2326 fps | 96.5% |
| Rottweil R 903 | <<locked>> | 84% | 32,068 psi | 52% | 2323 fps | 95% |
| Shooters World Long Rifle | <<locked>> | 96% | 44,411 psi | 72% | 2526 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 35,462 psi | 57% | 2392 fps | 98.4% |
| Shooters World Precision | <<locked>> | 80% | 32,750 psi | 53% | 2306 fps | 96% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 46,891 psi | 76% | 2533 fps | 98.9% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 53,113 psi | 86% | 2329 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 49,588 psi | 80% | 2612 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 35,969 psi | 58% | 2428 fps | 95.3% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 46,847 psi | 75% | 2533 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 42,699 psi | 69% | 2497 fps | 95.4% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 35,897 psi | 58% | 2382 fps | 95.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 38,159 psi | 61% | 2352 fps | 99.3% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 31,212 psi | 50% | 2221 fps | 98.7% |
| Somchem S321 | <<locked>> | 80% | 42,192 psi | 68% | 2503 fps | 98.7% |
| Somchem S335 | <<locked>> | 80% | 37,565 psi | 61% | 2352 fps | 99.6% |
| Somchem S341 | <<locked>> | 80% | 36,927 psi | 59% | 2395 fps | 95.7% |
| Somchem S355 | <<locked>> | 84% | 33,141 psi | 53% | 2333 fps | 95.1% |
| Somchem S365 | <<locked>> | 92% | 30,821 psi | 50% | 2356 fps | 95.4% |
| Vihtavuori N130 | <<locked>> | 80% | 43,410 psi | 70% | 2428 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 38,305 psi | 62% | 2356 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 33,402 psi | 54% | 2326 fps | 99.9% |
| Vihtavuori N140 | <<locked>> | 80% | 34,490 psi | 56% | 2329 fps | 99% |
| Vihtavuori N150 | <<locked>> | 82% | 29,472 psi | 47% | 2231 fps | 95.2% |
| Vihtavuori N160 | <<locked>> | 96% | 41,655 psi | 67% | 2516 fps | 95.6% |
| Vihtavuori N530 | <<locked>> | 80% | 39,102 psi | 63% | 2425 fps | 97.9% |
| Vihtavuori N540 | <<locked>> | 80% | 33,112 psi | 53% | 2313 fps | 98.3% |
| Vihtavuori N550 | <<locked>> | 96% | 40,857 psi | 66% | 2520 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 34,969 psi | 56% | 2352 fps | 95.6% |
| Winchester 748 | <<locked>> | 80% | 38,174 psi | 61% | 2461 fps | 98.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 34,925 psi | 56% | 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 94 powders for .375 Ruger loaded with the .375 | 240gr | Atomic 29 HP. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,841 fps; across all powders the maximum-charge window runs from 1,637 fps to 2,841 fps. Accurate 4350 gives the best case fill at 100 %, and 94 of the 94 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (428 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 240.0 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 52, Hodgdon LEVERevolution rank at the top here: for .375 Ruger with the .375 | 240gr | 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.