Load Specifications
Load data in caliber .375 R Verney-Carron with .375 | 250gr | Barnes Solid BT bullet and 95 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.
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You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 82% | 53,432 psi | 90% | 2733 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 52,257 psi | 88% | 2759 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 53,737 psi | 90% | 2825 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 51,256 psi | 86% | 2756 fps | 96.9% |
| Accurate 3100ᴾ | <<locked>> | 100% | 42,699 psi | 72% | 2710 fps | 96.9% |
| Accurate 4064 | <<locked>> | 88% | 52,475 psi | 88% | 2812 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 52,025 psi | 87% | 2894 fps | 99.7% |
| ADI AR 2206H | <<locked>> | 84% | 52,562 psi | 88% | 2838 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 53,519 psi | 90% | 2838 fps | 99.9% |
| ADI Benchmark 8208 | <<locked>> | 82% | 51,459 psi | 87% | 2785 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 52,344 psi | 88% | 2759 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 51,982 psi | 87% | 2953 fps | 99.9% |
| Alliant Power Pro Varmintᴾ | <<locked>> | 100% | 50,111 psi | 84% | 2861 fps | 95.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 53,621 psi | 90% | 2861 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 50,937 psi | 86% | 2831 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 98% | 53,316 psi | 90% | 2949 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 92% | 50,865 psi | 86% | 2930 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 40,698 psi | 68% | 2743 fps | 99.4% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 45,614 psi | 77% | 2910 fps | 98.9% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 52,243 psi | 88% | 2851 fps | 99.7% |
| Bofors RP3 | <<locked>> | 88% | 50,734 psi | 85% | 2825 fps | 100% |
| Bofors RP7 | <<locked>> | 92% | 51,024 psi | 86% | 2795 fps | 97.1% |
| Hodgdon Benchmark | <<locked>> | 82% | 53,229 psi | 90% | 2772 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 50,763 psi | 85% | 2815 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 51,619 psi | 87% | 2835 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 94% | 51,227 psi | 86% | 2887 fps | 97.8% |
| Hodgdon H4350 | <<locked>> | 92% | 51,982 psi | 87% | 2851 fps | 96.6% |
| Hodgdon H4895 | <<locked>> | 84% | 53,069 psi | 89% | 2848 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 53,040 psi | 89% | 2874 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 52,402 psi | 88% | 2877 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 51,605 psi | 87% | 2920 fps | 97.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,723 psi | 60% | 1755 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 50,836 psi | 85% | 2795 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 53,185 psi | 89% | 2828 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 53,026 psi | 89% | 2822 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 86% | 52,982 psi | 89% | 2802 fps | 97.9% |
| IMR 4350 | <<locked>> | 96% | 51,242 psi | 86% | 2822 fps | 97.2% |
| IMR 4451 Enduron | <<locked>> | 92% | 52,721 psi | 89% | 2825 fps | 97.8% |
| IMR 4831 | <<locked>> | 98% | 52,692 psi | 89% | 2887 fps | 99.7% |
| IMR 4895 | <<locked>> | 86% | 52,185 psi | 88% | 2861 fps | 100% |
| IMR 8208 XBR | <<locked>> | 82% | 51,459 psi | 87% | 2785 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 52,315 psi | 88% | 2812 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 52,156 psi | 88% | 2766 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 52,997 psi | 89% | 2818 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 52,243 psi | 88% | 2822 fps | 98.9% |
| Lovex S070 | <<locked>> | 96% | 53,142 psi | 89% | 2858 fps | 98.2% |
| Norma 201 | <<locked>> | 84% | 51,401 psi | 86% | 2782 fps | 100% |
| Norma 202 | <<locked>> | 84% | 51,851 psi | 87% | 2782 fps | 100% |
| Norma 203B | <<locked>> | 88% | 53,330 psi | 90% | 2867 fps | 100% |
| Norma 204 | <<locked>> | 96% | 51,561 psi | 87% | 2864 fps | 95.9% |
| Norma MRPᴾ | <<locked>> | 100% | 45,527 psi | 77% | 2864 fps | 96.5% |
| Norma URP | <<locked>> | 96% | 51,111 psi | 86% | 2881 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 86% | 50,357 psi | 85% | 2841 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 98% | 53,461 psi | 90% | 2933 fps | 98.9% |
| Ramshot TAC | <<locked>> | 82% | 51,561 psi | 87% | 2802 fps | 98.9% |
| Ramshot Wild Boar | <<locked>> | 82% | 51,314 psi | 86% | 2822 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,230 psi | 61% | 1795 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 51,837 psi | 87% | 2815 fps | 98.3% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 51,126 psi | 86% | 2894 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 50,589 psi | 85% | 2930 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 51,677 psi | 87% | 2913 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 51,082 psi | 86% | 2936 fps | 99.3% |
| Rottweil R 901 | <<locked>> | 82% | 52,431 psi | 88% | 2766 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 51,967 psi | 87% | 2782 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 50,807 psi | 85% | 2818 fps | 100% |
| Rottweil R 907 | <<locked>> | 92% | 51,024 psi | 86% | 2795 fps | 97.1% |
| Shooters World Long Rifle | <<locked>> | 94% | 52,243 psi | 88% | 2822 fps | 98.9% |
| Shooters World Match Rifle | <<locked>> | 84% | 52,315 psi | 88% | 2812 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 52,997 psi | 89% | 2818 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 53,142 psi | 89% | 2858 fps | 98.2% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 52,228 psi | 88% | 2877 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 53,577 psi | 90% | 2835 fps | 99.4% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 51,053 psi | 86% | 2808 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 52,678 psi | 89% | 2720 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 52,968 psi | 89% | 2720 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 52,315 psi | 88% | 2772 fps | 97.8% |
| Somchem S335 | <<locked>> | 84% | 52,243 psi | 88% | 2720 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 53,243 psi | 90% | 2828 fps | 100% |
| Somchem S355 | <<locked>> | 90% | 51,198 psi | 86% | 2818 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 52,620 psi | 88% | 2933 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 48,979 psi | 82% | 2818 fps | 96.7% |
| Vihtavuori N133 | <<locked>> | 84% | 53,011 psi | 89% | 2707 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 51,735 psi | 87% | 2749 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 52,402 psi | 88% | 2766 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 52,344 psi | 88% | 2792 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 53,563 psi | 90% | 2877 fps | 99.7% |
| Vihtavuori N530 | <<locked>> | 82% | 51,895 psi | 87% | 2785 fps | 100% |
| Vihtavuori N540 | <<locked>> | 86% | 50,618 psi | 85% | 2759 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 52,721 psi | 89% | 2884 fps | 99.5% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 44,846 psi | 75% | 2818 fps | 99.3% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 53,664 psi | 90% | 2851 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 51,822 psi | 87% | 2835 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 51,459 psi | 87% | 2890 fps | 97.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 36,506 psi | 61% | 2756 fps | 99.5% |
| Winchester StaBALL Match | <<locked>> | 84% | 50,821 psi | 85% | 2815 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 25.6"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 50,198 psi | 84% | 2687 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 42,946 psi | 72% | 2618 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 50,111 psi | 84% | 2772 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 44,976 psi | 76% | 2648 fps | 95.4% |
| Accurate 3100 | <<locked>> | 96% | 37,275 psi | 63% | 2602 fps | 95.3% |
| Accurate 4064 | <<locked>> | 80% | 40,611 psi | 68% | 2615 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 32,010 psi | 54% | 2497 fps | 95.3% |
| ADI AR 2206H | <<locked>> | 80% | 46,398 psi | 78% | 2733 fps | 99.6% |
| ADI AR 2208 | <<locked>> | 80% | 39,407 psi | 66% | 2582 fps | 98.1% |
| ADI Benchmark 8208 | <<locked>> | 80% | 48,428 psi | 81% | 2736 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 49,008 psi | 82% | 2717 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 42,235 psi | 71% | 2769 fps | 98.8% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 47,108 psi | 79% | 2808 fps | 95% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 39,233 psi | 66% | 2608 fps | 99.3% |
| Alliant Reloder-15 | <<locked>> | 80% | 42,061 psi | 71% | 2671 fps | 98.8% |
| Alliant Reloder-16 | <<locked>> | 82% | 32,358 psi | 54% | 2510 fps | 95.4% |
| Alliant Reloder-17 | 78.3 gr | 80% | 33,823 psi | 57% | 2579 fps | 97.9% |
| Alliant Reloder-23 | <<locked>> | 88% | 28,166 psi | 47% | 2418 fps | 95.2% |
| Alliant Reloder-26 | <<locked>> | 92% | 34,447 psi | 58% | 2651 fps | 95.5% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 45,716 psi | 77% | 2740 fps | 99% |
| Bofors RP3 | <<locked>> | 80% | 38,957 psi | 66% | 2612 fps | 99.3% |
| Bofors RP7 | <<locked>> | 88% | 45,049 psi | 76% | 2690 fps | 95.7% |
| Hodgdon Benchmark | <<locked>> | 80% | 49,966 psi | 84% | 2720 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 47,413 psi | 80% | 2759 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 39,668 psi | 67% | 2615 fps | 97.2% |
| Hodgdon H414 | <<locked>> | 88% | 42,047 psi | 71% | 2717 fps | 95.7% |
| Hodgdon H4350 | <<locked>> | 88% | 45,745 psi | 77% | 2740 fps | 95.1% |
| Hodgdon H4895 | <<locked>> | 80% | 46,818 psi | 79% | 2743 fps | 99.9% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 27,876 psi | 47% | 2356 fps | 95.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 42,859 psi | 72% | 2717 fps | 99.8% |
| Hodgdon Superformance | 93.1 gr | 90% | 44,628 psi | 75% | 2792 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,629 psi | 45% | 1568 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 44,817 psi | 75% | 2694 fps | 99.7% |
| IMR 3031 | <<locked>> | 80% | 46,760 psi | 79% | 2733 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 41,394 psi | 70% | 2618 fps | 98.7% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,816 psi | 74% | 2638 fps | 96% |
| IMR 4350 | <<locked>> | 90% | 42,467 psi | 71% | 2661 fps | 95% |
| IMR 4451 Enduron | <<locked>> | 84% | 41,408 psi | 70% | 2618 fps | 95.2% |
| IMR 4831 | <<locked>> | 82% | 31,125 psi | 52% | 2454 fps | 95% |
| IMR 4895 | <<locked>> | 80% | 43,091 psi | 72% | 2700 fps | 99.3% |
| IMR 8208 XBR | <<locked>> | 80% | 48,428 psi | 81% | 2736 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 45,658 psi | 77% | 2710 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 46,079 psi | 77% | 2664 fps | 99.6% |
| Lovex S062 | <<locked>> | 80% | 41,321 psi | 69% | 2618 fps | 99.7% |
| Lovex S065 | <<locked>> | 82% | 36,230 psi | 61% | 2513 fps | 95.2% |
| Lovex S070 | <<locked>> | 88% | 41,379 psi | 70% | 2644 fps | 95.6% |
| Norma 201 | <<locked>> | 80% | 45,324 psi | 76% | 2680 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 45,832 psi | 77% | 2690 fps | 100% |
| Norma 203B | <<locked>> | 80% | 41,437 psi | 70% | 2661 fps | 99.1% |
| Norma 204 | <<locked>> | 94% | 48,240 psi | 81% | 2808 fps | 95.1% |
| Norma MRP | <<locked>> | 98% | 42,496 psi | 71% | 2802 fps | 95.5% |
| Norma URP | <<locked>> | 82% | 32,445 psi | 55% | 2500 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 80% | 40,944 psi | 69% | 2671 fps | 98.9% |
| Ramshot Hunter | <<locked>> | 88% | 38,493 psi | 65% | 2648 fps | 95.5% |
| Ramshot TAC | <<locked>> | 80% | 48,298 psi | 81% | 2746 fps | 98.4% |
| Ramshot Wild Boar | <<locked>> | 80% | 47,979 psi | 81% | 2769 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,876 psi | 45% | 1601 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 40,089 psi | 67% | 2598 fps | 95.7% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 44,440 psi | 75% | 2776 fps | 99.2% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 36,027 psi | 61% | 2644 fps | 99.9% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 34,142 psi | 57% | 2572 fps | 95.8% |
| ReloadSwiss RS 70 | 85.5 gr | 86% | 36,463 psi | 61% | 2631 fps | 95.7% |
| Rottweil R 901 | <<locked>> | 80% | 49,356 psi | 83% | 2717 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 43,236 psi | 73% | 2635 fps | 99.8% |
| Rottweil R 903 | <<locked>> | 80% | 36,709 psi | 62% | 2559 fps | 98.7% |
| Rottweil R 907 | <<locked>> | 88% | 45,049 psi | 76% | 2690 fps | 95.7% |
| Shooters World Long Rifle | <<locked>> | 82% | 36,230 psi | 61% | 2513 fps | 95.2% |
| Shooters World Match Rifle | <<locked>> | 80% | 45,658 psi | 77% | 2710 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 41,321 psi | 69% | 2618 fps | 99.7% |
| Shooters World SW4350 | <<locked>> | 88% | 41,379 psi | 70% | 2644 fps | 95.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 37,536 psi | 63% | 2605 fps | 98.3% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,731 psi | 79% | 2723 fps | 98.6% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 44,831 psi | 75% | 2700 fps | 99.5% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,615 psi | 78% | 2628 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,943 psi | 65% | 2497 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 40,335 psi | 68% | 2559 fps | 95.1% |
| Somchem S335 | <<locked>> | 80% | 46,209 psi | 78% | 2628 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 46,557 psi | 78% | 2720 fps | 99.6% |
| Somchem S355 | <<locked>> | 80% | 37,333 psi | 63% | 2559 fps | 98.7% |
| Somchem S365 | <<locked>> | 80% | 27,253 psi | 46% | 2398 fps | 96.7% |
| Somchem S385 | <<locked>> | 96% | 42,888 psi | 72% | 2707 fps | 95.2% |
| Vihtavuori N133 | <<locked>> | 80% | 46,963 psi | 79% | 2618 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,815 psi | 72% | 2612 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 43,395 psi | 73% | 2621 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,621 psi | 60% | 2497 fps | 99.2% |
| Vihtavuori N160 | <<locked>> | 82% | 33,794 psi | 57% | 2500 fps | 95.8% |
| Vihtavuori N530 | <<locked>> | 80% | 48,631 psi | 82% | 2733 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 41,800 psi | 70% | 2615 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 33,330 psi | 56% | 2503 fps | 95.3% |
| Vihtavuori N555 | <<locked>> | 88% | 30,211 psi | 51% | 2493 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,546 psi | 53% | 2425 fps | 97.2% |
| Winchester 748 | <<locked>> | 80% | 48,530 psi | 82% | 2782 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 42,192 psi | 71% | 2720 fps | 95.7% |
| Winchester StaBALL HD | <<locked>> | 92% | 28,210 psi | 47% | 2493 fps | 95.7% |
| Winchester StaBALL Match | <<locked>> | 80% | 44,367 psi | 75% | 2707 fps | 99.7% |
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 R Verney-Carron loaded with the .375 | 250gr | Barnes Solid BT. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,953 fps; across all powders the maximum-charge window runs from 1,755 fps to 2,953 fps. Accurate 3100 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 (410 MPa), the top charges use 60–90 %, leaving at least 10 % headroom. The 250.0 gr projectile in 0.375" calls for a 1:15.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Power Pro Varmint, 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. ReloadSwiss RS 70, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for .375 R Verney-Carron with the .375 | 250gr | Barnes Solid BT 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.