
Load Specifications
Load data in caliber .300 H&H Mag. with .307 | 200gr | Frontier PH HPBT 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 Reloder-26, ReloadSwiss RS 70 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: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 82% | 54,940 psi | 88% | 2546 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 56,057 psi | 90% | 2615 fps | 99.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 53,476 psi | 86% | 2657 fps | 99.8% |
| Accurate 4064 | <<locked>> | 84% | 55,361 psi | 89% | 2598 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 56,014 psi | 90% | 2703 fps | 100% |
| Accurate MAGPROᴾ | <<locked>> | 100% | 55,637 psi | 89% | 2795 fps | 96.8% |
| ADI AR 2208 | <<locked>> | 86% | 55,477 psi | 89% | 2631 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 53,330 psi | 86% | 2697 fps | 98.3% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 54,520 psi | 87% | 2746 fps | 97.5% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 54,476 psi | 87% | 2743 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 53,316 psi | 85% | 2694 fps | 98.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 56,130 psi | 90% | 2651 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 56,376 psi | 90% | 2671 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 53,142 psi | 85% | 2707 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 54,259 psi | 87% | 2730 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 55,999 psi | 90% | 2736 fps | 98.8% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 53,374 psi | 86% | 2743 fps | 98.6% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 50,270 psi | 81% | 2674 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 43,845 psi | 70% | 2612 fps | 99.4% |
| Alliant Reloder-26 | <<locked>> | 98% | 53,867 psi | 86% | 2808 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 48,762 psi | 78% | 2667 fps | 97.7% |
| Bofors RP3 | <<locked>> | 84% | 53,417 psi | 86% | 2618 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 53,374 psi | 86% | 2743 fps | 98.6% |
| Bofors RP7 | <<locked>> | 90% | 56,405 psi | 90% | 2657 fps | 99.3% |
| Hodgdon H380 | <<locked>> | 84% | 53,795 psi | 86% | 2635 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 54,447 psi | 87% | 2703 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 88% | 54,418 psi | 87% | 2664 fps | 98.7% |
| Hodgdon H4831 | <<locked>> | 98% | 54,737 psi | 88% | 2694 fps | 96.8% |
| Hodgdon H4831 SC | <<locked>> | 98% | 53,388 psi | 86% | 2671 fps | 96.6% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 53,490 psi | 86% | 2635 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 55,042 psi | 88% | 2667 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 42,917 psi | 69% | 2638 fps | 96.9% |
| Hodgdon Superformance | <<locked>> | 90% | 54,462 psi | 87% | 2740 fps | 99.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,564 psi | 59% | 1627 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 55,738 psi | 89% | 2631 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 54,882 psi | 88% | 2612 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 53,925 psi | 86% | 2598 fps | 99.4% |
| IMR 4350 | <<locked>> | 92% | 53,969 psi | 87% | 2644 fps | 99.1% |
| IMR 4451 Enduron | <<locked>> | 88% | 54,694 psi | 88% | 2635 fps | 99.4% |
| IMR 4831 | <<locked>> | 94% | 56,304 psi | 90% | 2694 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 54,331 psi | 87% | 2648 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 56,289 psi | 90% | 2680 fps | 97.3% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 51,764 psi | 83% | 2713 fps | 97% |
| Lovex S060 | <<locked>> | 82% | 56,304 psi | 90% | 2595 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 55,042 psi | 88% | 2605 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 54,679 psi | 88% | 2631 fps | 99.9% |
| Lovex S070 | <<locked>> | 92% | 55,796 psi | 89% | 2667 fps | 99.7% |
| Lovex S071ᴾ | <<locked>> | 100% | 44,672 psi | 72% | 2523 fps | 98.9% |
| Norma 201 | <<locked>> | 82% | 56,304 psi | 90% | 2612 fps | 100% |
| Norma 203B | <<locked>> | 84% | 55,666 psi | 89% | 2657 fps | 100% |
| Norma 204 | <<locked>> | 92% | 54,520 psi | 87% | 2690 fps | 98.4% |
| Norma MRP | <<locked>> | 98% | 52,692 psi | 84% | 2762 fps | 99.4% |
| Norma URP | <<locked>> | 92% | 54,563 psi | 87% | 2687 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 56,434 psi | 90% | 2684 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 52,011 psi | 83% | 2730 fps | 97.4% |
| Ramshot Hunter | <<locked>> | 92% | 53,476 psi | 86% | 2694 fps | 99.8% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 46,427 psi | 74% | 2615 fps | 97.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,188 psi | 60% | 1663 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 53,635 psi | 86% | 2621 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 53,751 psi | 86% | 2720 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 55,811 psi | 89% | 2726 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 54,099 psi | 87% | 2753 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 42,815 psi | 69% | 2635 fps | 98% |
| Rottweil R 902 | <<locked>> | 82% | 53,824 psi | 86% | 2572 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 53,548 psi | 86% | 2615 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 54,955 psi | 88% | 2667 fps | 97.6% |
| Rottweil R 905 | <<locked>> | 98% | 55,201 psi | 89% | 2723 fps | 98.8% |
| Rottweil R 907 | <<locked>> | 90% | 56,405 psi | 90% | 2657 fps | 99.3% |
| Shooters World Long Rifle | <<locked>> | 90% | 54,679 psi | 88% | 2631 fps | 99.9% |
| Shooters World Precision | <<locked>> | 84% | 55,042 psi | 88% | 2605 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 55,796 psi | 89% | 2667 fps | 99.7% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 55,114 psi | 88% | 2674 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 56,231 psi | 90% | 2644 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 54,795 psi | 88% | 2510 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 54,302 psi | 87% | 2585 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 54,723 psi | 88% | 2717 fps | 98.7% |
| Somchem S355 | <<locked>> | 86% | 53,606 psi | 86% | 2612 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 53,055 psi | 85% | 2612 fps | 96.4% |
| Somchem S365 | <<locked>> | 94% | 53,983 psi | 87% | 2694 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 55,927 psi | 90% | 2700 fps | 99.3% |
| Vihtavuori N135 | <<locked>> | 82% | 54,143 psi | 87% | 2533 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 54,172 psi | 87% | 2546 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 54,766 psi | 88% | 2589 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 53,316 psi | 85% | 2635 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 51,547 psi | 83% | 2625 fps | 98.5% |
| Vihtavuori N540 | <<locked>> | 84% | 55,724 psi | 89% | 2589 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 55,825 psi | 90% | 2690 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 52,953 psi | 85% | 2700 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 53,069 psi | 85% | 2753 fps | 96.9% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 56,405 psi | 90% | 2654 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 54,737 psi | 88% | 2707 fps | 99.5% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 45,440 psi | 73% | 2733 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 56,173 psi | 90% | 2651 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 56,028 psi | 90% | 2697 fps | 98.7% |
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 2495 | <<locked>> | 80% | 51,735 psi | 83% | 2503 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 49,327 psi | 79% | 2516 fps | 98.3% |
| Accurate 3100 | <<locked>> | 84% | 31,241 psi | 50% | 2251 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 49,037 psi | 79% | 2513 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 37,260 psi | 60% | 2395 fps | 98.7% |
| Accurate MAGPRO | <<locked>> | 96% | 48,327 psi | 77% | 2677 fps | 95.1% |
| ADI AR 2208 | <<locked>> | 80% | 46,238 psi | 74% | 2490 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 88% | 41,075 psi | 66% | 2480 fps | 95.5% |
| ADI AR 2213 | <<locked>> | 96% | 47,674 psi | 76% | 2631 fps | 95.9% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 50,836 psi | 82% | 2690 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 41,350 psi | 66% | 2484 fps | 95.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 46,543 psi | 75% | 2510 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 49,792 psi | 80% | 2575 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,303 psi | 58% | 2402 fps | 98.8% |
| Alliant Reloder-17 | 55.2 gr | 80% | 41,147 psi | 66% | 2520 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 40,886 psi | 66% | 2477 fps | 95.6% |
| Alliant Reloder-22 | <<locked>> | 92% | 40,828 psi | 65% | 2520 fps | 95.7% |
| Alliant Reloder-23 | <<locked>> | 80% | 26,716 psi | 43% | 2182 fps | 96.8% |
| Alliant Reloder-25 | <<locked>> | 90% | 32,111 psi | 51% | 2346 fps | 95.9% |
| Alliant Reloder-26 | 58 gr | 82% | 30,385 psi | 49% | 2343 fps | 96.1% |
| Bofors RP15 | <<locked>> | 94% | 40,277 psi | 65% | 2510 fps | 95.4% |
| Bofors RP3 | <<locked>> | 80% | 47,007 psi | 75% | 2523 fps | 100% |
| Bofors RP5 | <<locked>> | 92% | 40,828 psi | 65% | 2520 fps | 95.7% |
| Bofors RP7 | <<locked>> | 80% | 41,307 psi | 66% | 2405 fps | 96.8% |
| Hodgdon H380 | <<locked>> | 80% | 47,181 psi | 76% | 2533 fps | 99.7% |
| Hodgdon H414 | <<locked>> | 80% | 39,233 psi | 63% | 2438 fps | 96.9% |
| Hodgdon H4350 | <<locked>> | 80% | 42,192 psi | 68% | 2457 fps | 96.3% |
| Hodgdon H4831 | <<locked>> | 94% | 47,834 psi | 77% | 2582 fps | 95.3% |
| Hodgdon H4831 SC | <<locked>> | 94% | 46,891 psi | 75% | 2566 fps | 95% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 33,924 psi | 54% | 2306 fps | 99.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 51,430 psi | 82% | 2618 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 98% | 40,306 psi | 65% | 2582 fps | 96% |
| Hodgdon Superformance | <<locked>> | 80% | 38,029 psi | 61% | 2444 fps | 96% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,209 psi | 44% | 1450 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 52,373 psi | 84% | 2582 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 48,631 psi | 78% | 2520 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 50,720 psi | 81% | 2546 fps | 99% |
| IMR 4350 | <<locked>> | 80% | 36,985 psi | 59% | 2339 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 80% | 42,786 psi | 69% | 2434 fps | 97.6% |
| IMR 4831 | <<locked>> | 80% | 35,940 psi | 58% | 2356 fps | 98.5% |
| IMR 4895 | <<locked>> | 80% | 51,053 psi | 82% | 2602 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 92% | 46,789 psi | 75% | 2530 fps | 95.2% |
| IMR 7828 SSC | <<locked>> | 96% | 45,484 psi | 73% | 2602 fps | 95.4% |
| Lovex S060 | <<locked>> | 80% | 53,243 psi | 85% | 2552 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 48,849 psi | 78% | 2516 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 40,379 psi | 65% | 2392 fps | 98.3% |
| Lovex S070 | <<locked>> | 80% | 38,464 psi | 62% | 2372 fps | 96.8% |
| Lovex S071 | <<locked>> | 90% | 32,561 psi | 52% | 2283 fps | 95.7% |
| Norma 201 | <<locked>> | 80% | 53,200 psi | 85% | 2572 fps | 100% |
| Norma 203B | <<locked>> | 80% | 49,124 psi | 79% | 2562 fps | 100% |
| Norma 204 | <<locked>> | 84% | 41,524 psi | 67% | 2470 fps | 95.5% |
| Norma MRP | <<locked>> | 86% | 35,056 psi | 56% | 2425 fps | 95.2% |
| Norma URP | <<locked>> | 80% | 37,028 psi | 59% | 2388 fps | 98.5% |
| Ramshot Big Game | <<locked>> | 80% | 49,298 psi | 79% | 2585 fps | 100% |
| Ramshot Grand | <<locked>> | 96% | 45,237 psi | 73% | 2612 fps | 95.7% |
| Ramshot Hunter | <<locked>> | 80% | 35,868 psi | 58% | 2379 fps | 96.7% |
| Ramshot Magnum | <<locked>> | 94% | 37,420 psi | 60% | 2438 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,847 psi | 45% | 1486 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 47,224 psi | 76% | 2520 fps | 99% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 43,714 psi | 70% | 2569 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 36,898 psi | 59% | 2411 fps | 98.4% |
| ReloadSwiss RS 70 | 56 gr | 80% | 35,839 psi | 57% | 2418 fps | 97.8% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 37,115 psi | 60% | 2503 fps | 95.9% |
| Rottweil R 902 | <<locked>> | 80% | 50,560 psi | 81% | 2523 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 44,179 psi | 71% | 2474 fps | 100% |
| Rottweil R 904 | <<locked>> | 90% | 45,455 psi | 73% | 2513 fps | 95.5% |
| Rottweil R 905 | <<locked>> | 88% | 39,813 psi | 64% | 2461 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 80% | 41,307 psi | 66% | 2405 fps | 96.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,379 psi | 65% | 2392 fps | 98.3% |
| Shooters World Precision | <<locked>> | 80% | 48,849 psi | 78% | 2516 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 38,464 psi | 62% | 2372 fps | 96.8% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 45,223 psi | 73% | 2523 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 52,663 psi | 84% | 2595 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 45,440 psi | 73% | 2382 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 39,378 psi | 63% | 2339 fps | 96.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 39,436 psi | 63% | 2454 fps | 95.3% |
| Somchem S355 | <<locked>> | 80% | 44,657 psi | 72% | 2474 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 49,661 psi | 80% | 2556 fps | 95.7% |
| Somchem S365 | <<locked>> | 80% | 33,518 psi | 54% | 2349 fps | 99.9% |
| Somchem S385 | <<locked>> | 86% | 38,058 psi | 61% | 2395 fps | 95.8% |
| Vihtavuori N135 | <<locked>> | 80% | 50,778 psi | 81% | 2487 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 50,923 psi | 82% | 2503 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 42,438 psi | 68% | 2405 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 38,450 psi | 62% | 2388 fps | 98.8% |
| Vihtavuori N165 | <<locked>> | 90% | 37,333 psi | 60% | 2375 fps | 95.1% |
| Vihtavuori N540 | <<locked>> | 80% | 49,110 psi | 79% | 2500 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 37,855 psi | 61% | 2388 fps | 98.5% |
| Vihtavuori N555 | <<locked>> | 80% | 29,341 psi | 47% | 2251 fps | 96.9% |
| Vihtavuori N560 | <<locked>> | 94% | 46,499 psi | 75% | 2641 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 37,521 psi | 60% | 2362 fps | 99.8% |
| Winchester 760 | <<locked>> | 80% | 39,233 psi | 63% | 2438 fps | 96.9% |
| Winchester StaBALL HD | <<locked>> | 80% | 23,511 psi | 38% | 2152 fps | 95.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 52,837 psi | 85% | 2605 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 90% | 39,784 psi | 64% | 2428 fps | 95.1% |
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 .300 H&H Mag. loaded with the .307 | 200gr | Frontier PH HPBT. Alliant Reloder-26 delivers the highest muzzle velocity at 2,808 fps; across all powders the maximum-charge window runs from 1,627 fps to 2,808 fps. Accurate 3100 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 (430 MPa), the top charges use 59–90 %, leaving at least 10 % headroom. The 200.0 gr projectile in 0.307" calls for a 1:10.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate MAGPRO, ADI AR 2213 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 Reloder-26, ReloadSwiss RS 70, Alliant Reloder-17 rank at the top here: for .300 H&H Mag. with the .307 | 200gr | Frontier PH HPBT 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.