Load Specifications
Load data in caliber .375 Ruger with .376 | 250gr | Peregrine VLR-4 bullet and 95 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% | 55,172 psi | 89% | 2562 fps | 100% |
| Accurate 2200 | <<locked>> | 82% | 55,593 psi | 90% | 2654 fps | 99% |
| Accurate 2460 | <<locked>> | 86% | 53,592 psi | 86% | 2582 fps | 100% |
| Accurate 2495 | <<locked>> | 96% | 55,579 psi | 90% | 2612 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 55,259 psi | 89% | 2638 fps | 100% |
| Accurate 4064 | <<locked>> | 98% | 55,129 psi | 89% | 2648 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 44,135 psi | 71% | 2549 fps | 96.8% |
| Accurate LT-30 | <<locked>> | 84% | 55,288 psi | 89% | 2516 fps | 100% |
| Accurate LT-32 | <<locked>> | 84% | 55,738 psi | 90% | 2539 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 54,418 psi | 88% | 2644 fps | 99.4% |
| ADI AR 2208 | <<locked>> | 98% | 55,390 psi | 89% | 2638 fps | 99.1% |
| ADI AR 2219 | <<locked>> | 84% | 56,043 psi | 90% | 2631 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 53,751 psi | 87% | 2605 fps | 99.8% |
| Alliant AR-Comp | <<locked>> | 90% | 53,200 psi | 86% | 2589 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 55,085 psi | 89% | 2703 fps | 99.7% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 53,896 psi | 87% | 2740 fps | 99% |
| Alliant Reloder- TS 15.5 | <<locked>> | 98% | 54,331 psi | 88% | 2654 fps | 99.8% |
| Alliant Reloder-10x | <<locked>> | 86% | 55,042 psi | 89% | 2572 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 55,288 psi | 89% | 2674 fps | 99.2% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 44,672 psi | 72% | 2562 fps | 97% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 51,561 psi | 83% | 2707 fps | 99.6% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 54,578 psi | 88% | 2513 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 54,041 psi | 87% | 2651 fps | 98.7% |
| Bofors RP3 | <<locked>> | 98% | 54,679 psi | 88% | 2667 fps | 99.8% |
| Hodgdon Benchmark | <<locked>> | 90% | 56,043 psi | 90% | 2595 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 92% | 56,043 psi | 90% | 2677 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 88% | 54,244 psi | 87% | 2717 fps | 99.2% |
| Hodgdon H322 | <<locked>> | 86% | 54,331 psi | 88% | 2608 fps | 100% |
| Hodgdon H335 | <<locked>> | 86% | 55,651 psi | 90% | 2635 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 52,852 psi | 85% | 2628 fps | 97.9% |
| Hodgdon H4895 | <<locked>> | 92% | 54,868 psi | 88% | 2654 fps | 99.7% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 40,654 psi | 65% | 2454 fps | 97.6% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 53,301 psi | 86% | 2677 fps | 99.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,301 psi | 55% | 1588 fps | 100% |
| Hodgdon VARGET | <<locked>> | 92% | 52,866 psi | 85% | 2608 fps | 99.5% |
| IMR 3031 | <<locked>> | 92% | 53,983 psi | 87% | 2644 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 54,708 psi | 88% | 2621 fps | 99.1% |
| IMR 4166 Enduron | <<locked>> | 94% | 55,695 psi | 90% | 2602 fps | 96.2% |
| IMR 4198 | <<locked>> | 86% | 55,651 psi | 90% | 2536 fps | 100% |
| IMR 4451 Enduronᴾ | <<locked>> | 100% | 54,679 psi | 88% | 2615 fps | 95.9% |
| IMR 4831ᴾ | <<locked>> | 100% | 42,380 psi | 68% | 2500 fps | 96.4% |
| IMR 4895 | <<locked>> | 94% | 53,098 psi | 86% | 2654 fps | 99.4% |
| IMR 8208 XBR | <<locked>> | 90% | 53,751 psi | 87% | 2605 fps | 99.8% |
| Lovex D073.5 | <<locked>> | 86% | 53,461 psi | 86% | 2589 fps | 100% |
| Lovex D073.6 | <<locked>> | 92% | 53,069 psi | 85% | 2621 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 54,679 psi | 88% | 2582 fps | 99.4% |
| Lovex S062 | <<locked>> | 96% | 53,969 psi | 87% | 2618 fps | 99.9% |
| Lovex S065ᴾ | <<locked>> | 100% | 49,821 psi | 80% | 2556 fps | 96.5% |
| Norma 200 | <<locked>> | 82% | 54,665 psi | 88% | 2546 fps | 100% |
| Norma 201 | <<locked>> | 92% | 52,895 psi | 85% | 2595 fps | 99.8% |
| Norma 202 | <<locked>> | 92% | 53,200 psi | 86% | 2602 fps | 100% |
| Norma 203B | <<locked>> | 96% | 54,331 psi | 88% | 2661 fps | 99.4% |
| Norma URPᴾ | <<locked>> | 100% | 44,570 psi | 72% | 2549 fps | 96.8% |
| Ramshot Big Game | <<locked>> | 96% | 55,129 psi | 89% | 2687 fps | 99.4% |
| Ramshot TAC | <<locked>> | 90% | 54,418 psi | 88% | 2615 fps | 97.6% |
| Ramshot Wild Boar | <<locked>> | 90% | 53,258 psi | 86% | 2631 fps | 99.3% |
| Ramshot X-Terminator | <<locked>> | 88% | 55,201 psi | 89% | 2608 fps | 99.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,548 psi | 56% | 1624 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 53,548 psi | 86% | 2595 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 53,693 psi | 86% | 2608 fps | 96.5% |
| ReloadSwiss RS 52 | <<locked>> | 94% | 55,274 psi | 89% | 2736 fps | 99.2% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 55,158 psi | 89% | 2766 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 44,135 psi | 71% | 2566 fps | 96.4% |
| Rottweil R 901 | <<locked>> | 90% | 53,592 psi | 86% | 2582 fps | 100% |
| Rottweil R 902 | <<locked>> | 94% | 53,084 psi | 86% | 2589 fps | 99.8% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 54,302 psi | 87% | 2654 fps | 99.7% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 49,821 psi | 80% | 2556 fps | 96.5% |
| Shooters World Match Rifle | <<locked>> | 92% | 53,069 psi | 85% | 2621 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 53,969 psi | 87% | 2618 fps | 99.9% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 53,374 psi | 86% | 2566 fps | 99.7% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 55,579 psi | 90% | 2293 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 52,562 psi | 85% | 2589 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 53,026 psi | 85% | 2667 fps | 99.3% |
| SNPE Vectan SP 3 | <<locked>> | 86% | 56,115 psi | 90% | 2592 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 92% | 55,854 psi | 90% | 2638 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 52,779 psi | 85% | 2615 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 55,143 psi | 89% | 2549 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 54,998 psi | 89% | 2546 fps | 100% |
| Somchem S321 | <<locked>> | 88% | 55,056 psi | 89% | 2638 fps | 100% |
| Somchem S335 | <<locked>> | 92% | 54,201 psi | 87% | 2546 fps | 100% |
| Somchem S341 | <<locked>> | 92% | 55,303 psi | 89% | 2631 fps | 99.4% |
| Somchem S355ᴾ | <<locked>> | 100% | 55,056 psi | 89% | 2654 fps | 99.7% |
| Somchem S365ᴾ | <<locked>> | 100% | 39,523 psi | 64% | 2497 fps | 98.7% |
| Vihtavuori N130 | <<locked>> | 88% | 54,969 psi | 89% | 2523 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 55,100 psi | 89% | 2536 fps | 100% |
| Vihtavuori N135 | <<locked>> | 96% | 55,796 psi | 90% | 2608 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 53,896 psi | 87% | 2582 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 53,287 psi | 86% | 2595 fps | 99.9% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 47,065 psi | 76% | 2552 fps | 97.2% |
| Vihtavuori N530 | <<locked>> | 90% | 54,230 psi | 87% | 2605 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 96% | 55,666 psi | 90% | 2621 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 46,006 psi | 74% | 2552 fps | 96.8% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 48,428 psi | 78% | 2543 fps | 99.1% |
| Winchester 748 | <<locked>> | 90% | 53,417 psi | 86% | 2648 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 94% | 55,956 psi | 90% | 2671 fps | 99.8% |
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% | 40,147 psi | 65% | 2352 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 52,011 psi | 84% | 2602 fps | 98.5% |
| Accurate 2460 | <<locked>> | 80% | 43,511 psi | 70% | 2441 fps | 99.8% |
| Accurate 2495 | <<locked>> | 80% | 32,198 psi | 52% | 2257 fps | 99.9% |
| Accurate 2520 | <<locked>> | 80% | 38,870 psi | 63% | 2395 fps | 99.2% |
| Accurate 4064 | <<locked>> | 80% | 30,516 psi | 49% | 2238 fps | 98.2% |
| Accurate 4350 | <<locked>> | 96% | 38,116 psi | 61% | 2441 fps | 95.1% |
| Accurate LT-30 | <<locked>> | 80% | 49,008 psi | 79% | 2434 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 49,385 psi | 80% | 2454 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 36,956 psi | 60% | 2349 fps | 96.1% |
| ADI AR 2208 | <<locked>> | 86% | 38,000 psi | 61% | 2352 fps | 95.5% |
| ADI AR 2219 | <<locked>> | 80% | 48,791 psi | 79% | 2536 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 39,030 psi | 63% | 2369 fps | 97.9% |
| Alliant AR-Comp | <<locked>> | 80% | 37,710 psi | 61% | 2375 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 45,107 psi | 73% | 2549 fps | 98.6% |
| Alliant Power Pro 2000-MR | 66.4 gr | 84% | 38,174 psi | 61% | 2457 fps | 95% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 32,256 psi | 52% | 2270 fps | 95.5% |
| Alliant Reloder-10x | <<locked>> | 80% | 45,614 psi | 73% | 2448 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 37,434 psi | 60% | 2379 fps | 95.6% |
| Alliant Reloder-16 | <<locked>> | 96% | 39,407 psi | 63% | 2461 fps | 95.3% |
| Alliant Reloder-17 | <<locked>> | 88% | 34,360 psi | 55% | 2379 fps | 95.3% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 47,906 psi | 77% | 2428 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 38,464 psi | 62% | 2395 fps | 95.2% |
| Bofors RP3 | <<locked>> | 82% | 31,488 psi | 51% | 2267 fps | 95.4% |
| Hodgdon Benchmark | <<locked>> | 80% | 40,988 psi | 66% | 2369 fps | 98.8% |
| Hodgdon BL-C2 | <<locked>> | 80% | 36,840 psi | 59% | 2372 fps | 98% |
| Hodgdon CFE223 | <<locked>> | 80% | 40,669 psi | 66% | 2493 fps | 96.6% |
| Hodgdon H322 | <<locked>> | 80% | 44,527 psi | 72% | 2470 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 45,179 psi | 73% | 2487 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 40,277 psi | 65% | 2421 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 37,217 psi | 60% | 2362 fps | 96.8% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 33,576 psi | 54% | 2310 fps | 95.2% |
| Hodgdon LEVERevolution | 62 gr | 80% | 33,170 psi | 53% | 2320 fps | 95.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,367 psi | 41% | 1417 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 35,926 psi | 58% | 2320 fps | 96.3% |
| IMR 3031 | <<locked>> | 80% | 36,027 psi | 58% | 2372 fps | 99.9% |
| IMR 4064 | <<locked>> | 84% | 37,449 psi | 60% | 2336 fps | 95.7% |
| IMR 4166 Enduron | <<locked>> | 92% | 52,272 psi | 84% | 2552 fps | 95.4% |
| IMR 4198 | <<locked>> | 80% | 46,485 psi | 75% | 2418 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 98% | 51,271 psi | 83% | 2566 fps | 95.1% |
| IMR 4831 | <<locked>> | 98% | 39,581 psi | 64% | 2451 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 33,634 psi | 54% | 2310 fps | 95% |
| IMR 8208 XBR | <<locked>> | 80% | 39,030 psi | 63% | 2369 fps | 97.9% |
| Lovex D073.5 | <<locked>> | 80% | 43,424 psi | 70% | 2444 fps | 99.4% |
| Lovex D073.6 | <<locked>> | 80% | 35,041 psi | 56% | 2329 fps | 98.5% |
| Lovex S060 | <<locked>> | 80% | 37,739 psi | 61% | 2303 fps | 96.3% |
| Lovex S062 | <<locked>> | 80% | 32,343 psi | 52% | 2244 fps | 96% |
| Lovex S065 | <<locked>> | 96% | 43,976 psi | 71% | 2461 fps | 95% |
| Norma 200 | <<locked>> | 80% | 51,430 psi | 83% | 2503 fps | 100% |
| Norma 201 | <<locked>> | 80% | 36,056 psi | 58% | 2310 fps | 97.2% |
| Norma 202 | <<locked>> | 80% | 36,143 psi | 58% | 2329 fps | 99.2% |
| Norma 203B | <<locked>> | 82% | 34,374 psi | 55% | 2316 fps | 95.2% |
| Norma URP | <<locked>> | 96% | 38,957 psi | 63% | 2448 fps | 95.1% |
| Ramshot Big Game | <<locked>> | 84% | 36,477 psi | 59% | 2379 fps | 95.6% |
| Ramshot TAC | <<locked>> | 84% | 44,512 psi | 72% | 2461 fps | 95.4% |
| Ramshot Wild Boar | <<locked>> | 80% | 37,869 psi | 61% | 2375 fps | 96.3% |
| Ramshot X-Terminator | <<locked>> | 80% | 42,395 psi | 68% | 2411 fps | 97.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,527 psi | 41% | 1453 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 43,787 psi | 71% | 2451 fps | 99.6% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 46,978 psi | 76% | 2510 fps | 95% |
| ReloadSwiss RS 52 | 62.8 gr | 82% | 36,187 psi | 58% | 2411 fps | 95.1% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 29,979 psi | 48% | 2280 fps | 96% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 41,263 psi | 66% | 2516 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 39,552 psi | 64% | 2362 fps | 99.5% |
| Rottweil R 902 | <<locked>> | 80% | 34,171 psi | 55% | 2264 fps | 96.6% |
| Rottweil R 903 | <<locked>> | 84% | 31,546 psi | 51% | 2260 fps | 95% |
| Shooters World Long Rifle | <<locked>> | 96% | 43,976 psi | 71% | 2461 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 35,041 psi | 56% | 2329 fps | 98.5% |
| Shooters World Precision | <<locked>> | 80% | 32,343 psi | 52% | 2244 fps | 96% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 46,383 psi | 75% | 2464 fps | 99% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 52,750 psi | 85% | 2260 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 49,081 psi | 79% | 2539 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 35,549 psi | 57% | 2362 fps | 95.4% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 46,398 psi | 75% | 2464 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 42,264 psi | 68% | 2431 fps | 95.4% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 35,520 psi | 57% | 2320 fps | 95.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 37,782 psi | 61% | 2287 fps | 99.3% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 30,879 psi | 50% | 2162 fps | 98.8% |
| Somchem S321 | <<locked>> | 80% | 41,771 psi | 67% | 2438 fps | 98.7% |
| Somchem S335 | <<locked>> | 80% | 37,304 psi | 60% | 2290 fps | 99.7% |
| Somchem S341 | <<locked>> | 80% | 36,492 psi | 59% | 2329 fps | 95.8% |
| Somchem S355 | <<locked>> | 84% | 32,895 psi | 53% | 2277 fps | 95.3% |
| Somchem S365 | <<locked>> | 92% | 30,458 psi | 49% | 2293 fps | 95.5% |
| Vihtavuori N130 | <<locked>> | 80% | 43,004 psi | 69% | 2362 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 37,927 psi | 61% | 2293 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 32,996 psi | 53% | 2264 fps | 99.9% |
| Vihtavuori N140 | <<locked>> | 80% | 34,127 psi | 55% | 2267 fps | 99% |
| Vihtavuori N150 | <<locked>> | 82% | 29,240 psi | 47% | 2172 fps | 95.4% |
| Vihtavuori N160 | <<locked>> | 96% | 41,191 psi | 66% | 2451 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 80% | 38,812 psi | 63% | 2362 fps | 98% |
| Vihtavuori N540 | <<locked>> | 80% | 32,721 psi | 53% | 2251 fps | 98.3% |
| Vihtavuori N550 | <<locked>> | 96% | 40,292 psi | 65% | 2454 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 34,650 psi | 56% | 2293 fps | 95.6% |
| Winchester 748 | <<locked>> | 80% | 37,637 psi | 61% | 2395 fps | 98.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 34,606 psi | 56% | 2316 fps | 96% |
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 95 powders for .375 Ruger loaded with the .376 | 250gr | Peregrine VLR-4. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,766 fps; across all powders the maximum-charge window runs from 1,588 fps to 2,766 fps. Accurate 4350 gives the best case fill at 100 %, and 95 of the 95 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 250.0 gr projectile in 0.376" calls for a 1:16.0 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 .376 | 250gr | Peregrine VLR-4 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.