Load Specifications
Load data in caliber .280 Ackley Improved with .284 | 180gr | Berger Hybrid Target 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 Reloder-26, Norma MRP and Vihtavuori N560.
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% | 58,595 psi | 90% | 2526 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 55,535 psi | 85% | 2559 fps | 99.6% |
| Accurate 3100ᴾ | <<locked>> | 100% | 57,914 psi | 89% | 2664 fps | 100% |
| Accurate 4064 | <<locked>> | 82% | 55,521 psi | 85% | 2539 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 56,376 psi | 87% | 2654 fps | 100% |
| Accurate MAGPRO | <<locked>> | 98% | 56,304 psi | 87% | 2756 fps | 97.8% |
| ADI AR 2208 | <<locked>> | 86% | 58,378 psi | 90% | 2615 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 56,971 psi | 88% | 2700 fps | 99.4% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 58,276 psi | 90% | 2756 fps | 98.8% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 37,579 psi | 58% | 2451 fps | 97.5% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 58,653 psi | 90% | 2740 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 57,087 psi | 88% | 2697 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 55,941 psi | 86% | 2589 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 56,217 psi | 86% | 2612 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 56,840 psi | 87% | 2697 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 58,465 psi | 90% | 2720 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 56,347 psi | 87% | 2690 fps | 99.3% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 57,508 psi | 88% | 2749 fps | 99.6% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 54,694 psi | 84% | 2674 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 47,282 psi | 73% | 2625 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 96% | 54,563 psi | 84% | 2759 fps | 100% |
| Baschieri & Pellagri 109ᴾ | <<locked>> | 100% | 57,058 psi | 88% | 2664 fps | 95.8% |
| Bofors RP15ᴾ | <<locked>> | 100% | 52,866 psi | 81% | 2684 fps | 99% |
| Bofors RP3 | <<locked>> | 84% | 57,145 psi | 88% | 2608 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 43,134 psi | 66% | 2556 fps | 96.7% |
| Bofors RP5ᴾ | <<locked>> | 100% | 57,508 psi | 88% | 2749 fps | 99.6% |
| Bofors RP7 | <<locked>> | 88% | 56,115 psi | 86% | 2605 fps | 99.7% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 46,891 psi | 72% | 2572 fps | 97.6% |
| Hodgdon H380 | <<locked>> | 84% | 57,276 psi | 88% | 2628 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 58,218 psi | 90% | 2703 fps | 100% |
| Hodgdon H4350 | <<locked>> | 88% | 57,870 psi | 89% | 2664 fps | 99.6% |
| Hodgdon H4831 | <<locked>> | 98% | 58,421 psi | 90% | 2700 fps | 98.3% |
| Hodgdon H4831 SC | <<locked>> | 98% | 57,421 psi | 88% | 2684 fps | 98.1% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 57,319 psi | 88% | 2628 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 58,711 psi | 90% | 2654 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 46,253 psi | 71% | 2667 fps | 98.8% |
| Hodgdon Superformance | <<locked>> | 88% | 54,607 psi | 84% | 2690 fps | 99.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,709 psi | 56% | 1598 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 58,813 psi | 90% | 2615 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 57,957 psi | 89% | 2598 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 56,724 psi | 87% | 2589 fps | 99.9% |
| IMR 4350 | <<locked>> | 92% | 57,087 psi | 88% | 2635 fps | 99.8% |
| IMR 4451 Enduron | <<locked>> | 88% | 57,580 psi | 89% | 2628 fps | 99.9% |
| IMR 4831 | <<locked>> | 92% | 56,652 psi | 87% | 2644 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 57,711 psi | 89% | 2638 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 56,173 psi | 86% | 2631 fps | 98.1% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 55,912 psi | 86% | 2733 fps | 98.6% |
| Lovex S062 | <<locked>> | 84% | 58,233 psi | 90% | 2589 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 58,073 psi | 89% | 2625 fps | 100% |
| Lovex S070 | <<locked>> | 90% | 55,854 psi | 86% | 2618 fps | 99.9% |
| Lovex S071ᴾ | <<locked>> | 100% | 48,327 psi | 74% | 2533 fps | 99.7% |
| Norma 203B | <<locked>> | 82% | 55,564 psi | 85% | 2602 fps | 100% |
| Norma 204 | <<locked>> | 92% | 58,044 psi | 89% | 2690 fps | 99.4% |
| Norma MRP | <<locked>> | 98% | 57,305 psi | 88% | 2776 fps | 100% |
| Norma URP | <<locked>> | 92% | 58,276 psi | 90% | 2680 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 56,420 psi | 87% | 2628 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 56,391 psi | 87% | 2749 fps | 98.9% |
| Ramshot Hunter | <<locked>> | 92% | 57,072 psi | 88% | 2690 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 50,430 psi | 78% | 2635 fps | 99.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,521 psi | 58% | 1637 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 57,058 psi | 88% | 2618 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 57,986 psi | 89% | 2710 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 55,985 psi | 86% | 2674 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 58,436 psi | 90% | 2756 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 46,340 psi | 71% | 2667 fps | 99.5% |
| Rottweil R 902 | <<locked>> | 82% | 56,753 psi | 87% | 2552 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 56,985 psi | 88% | 2602 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 58,494 psi | 90% | 2671 fps | 98.8% |
| Rottweil R 905 | <<locked>> | 96% | 55,753 psi | 86% | 2677 fps | 99.4% |
| Rottweil R 907 | <<locked>> | 88% | 56,115 psi | 86% | 2605 fps | 99.7% |
| Shooters World Long Rifle | <<locked>> | 90% | 58,073 psi | 89% | 2625 fps | 100% |
| Shooters World Precision | <<locked>> | 84% | 58,233 psi | 90% | 2589 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 55,854 psi | 86% | 2618 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 58,711 psi | 90% | 2664 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 57,638 psi | 89% | 2487 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 57,580 psi | 89% | 2582 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 55,288 psi | 85% | 2674 fps | 99.3% |
| Somchem S355 | <<locked>> | 86% | 56,898 psi | 88% | 2598 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 56,681 psi | 87% | 2618 fps | 97.9% |
| Somchem S365 | <<locked>> | 94% | 58,334 psi | 90% | 2684 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 56,304 psi | 87% | 2654 fps | 99.7% |
| Vihtavuori N135 | <<locked>> | 82% | 57,217 psi | 88% | 2510 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 57,435 psi | 88% | 2530 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 58,276 psi | 90% | 2575 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 56,956 psi | 88% | 2631 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 55,593 psi | 86% | 2631 fps | 99.5% |
| Vihtavuori N540 | <<locked>> | 82% | 55,434 psi | 85% | 2526 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 55,941 psi | 86% | 2638 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 57,290 psi | 88% | 2697 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 57,421 psi | 88% | 2769 fps | 98.5% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 49,356 psi | 76% | 2635 fps | 97.3% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 56,362 psi | 87% | 2595 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 58,581 psi | 90% | 2707 fps | 100% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 50,430 psi | 78% | 2746 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 56,275 psi | 87% | 2651 fps | 99.3% |
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% | 54,752 psi | 84% | 2484 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 51,996 psi | 80% | 2510 fps | 99.2% |
| Accurate 3100 | <<locked>> | 80% | 29,588 psi | 46% | 2165 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 51,967 psi | 80% | 2493 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 40,074 psi | 62% | 2398 fps | 99.6% |
| Accurate MAGPRO | <<locked>> | 92% | 45,484 psi | 70% | 2582 fps | 95.4% |
| ADI AR 2208 | <<locked>> | 80% | 48,762 psi | 75% | 2480 fps | 100% |
| ADI AR 2209 | <<locked>> | 84% | 38,696 psi | 60% | 2388 fps | 95.8% |
| ADI AR 2213 | <<locked>> | 90% | 41,814 psi | 64% | 2477 fps | 95.2% |
| ADI AR 2225 | <<locked>> | 96% | 33,185 psi | 51% | 2339 fps | 95.5% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 54,447 psi | 84% | 2684 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 82% | 36,405 psi | 56% | 2336 fps | 95% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 49,530 psi | 76% | 2503 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 52,634 psi | 81% | 2562 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 38,740 psi | 60% | 2408 fps | 99.7% |
| Alliant Reloder-17 | <<locked>> | 80% | 44,222 psi | 68% | 2520 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 38,392 psi | 59% | 2382 fps | 95.8% |
| Alliant Reloder-22 | <<locked>> | 86% | 36,216 psi | 56% | 2379 fps | 95.2% |
| Alliant Reloder-23 | <<locked>> | 80% | 28,572 psi | 44% | 2195 fps | 98.5% |
| Alliant Reloder-25 | <<locked>> | 84% | 28,601 psi | 44% | 2208 fps | 95.3% |
| Alliant Reloder-26 | 49.3 gr | 80% | 30,661 psi | 47% | 2306 fps | 97.4% |
| Baschieri & Pellagri 109 | <<locked>> | 98% | 53,664 psi | 83% | 2612 fps | 95% |
| Bofors RP15 | <<locked>> | 90% | 38,232 psi | 59% | 2421 fps | 95.8% |
| Bofors RP3 | <<locked>> | 80% | 49,937 psi | 77% | 2513 fps | 100% |
| Bofors RP30 | <<locked>> | 98% | 40,495 psi | 62% | 2503 fps | 95.8% |
| Bofors RP5 | <<locked>> | 86% | 36,216 psi | 56% | 2379 fps | 95.2% |
| Bofors RP7 | <<locked>> | 80% | 43,816 psi | 67% | 2408 fps | 98.2% |
| Hodgdon H1000 | <<locked>> | 96% | 40,843 psi | 63% | 2457 fps | 95.8% |
| Hodgdon H380 | <<locked>> | 80% | 50,140 psi | 77% | 2526 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 41,887 psi | 64% | 2444 fps | 98.3% |
| Hodgdon H4350 | <<locked>> | 80% | 44,701 psi | 69% | 2457 fps | 97.8% |
| Hodgdon H4831 | <<locked>> | 90% | 44,860 psi | 69% | 2490 fps | 95.5% |
| Hodgdon H4831 SC | <<locked>> | 90% | 43,845 psi | 67% | 2470 fps | 95.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 36,347 psi | 56% | 2306 fps | 99.9% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 54,955 psi | 85% | 2605 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 92% | 35,810 psi | 55% | 2434 fps | 95.3% |
| Hodgdon Superformance | <<locked>> | 80% | 40,770 psi | 63% | 2461 fps | 97.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,383 psi | 42% | 1424 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 55,376 psi | 85% | 2569 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 51,285 psi | 79% | 2507 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 53,476 psi | 82% | 2543 fps | 99.7% |
| IMR 4350 | <<locked>> | 80% | 39,392 psi | 61% | 2346 fps | 97.2% |
| IMR 4451 Enduron | <<locked>> | 80% | 45,194 psi | 70% | 2434 fps | 98.7% |
| IMR 4831 | <<locked>> | 80% | 38,392 psi | 59% | 2356 fps | 99.4% |
| IMR 4895 | <<locked>> | 80% | 54,027 psi | 83% | 2585 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 88% | 43,990 psi | 68% | 2434 fps | 95.5% |
| IMR 7828 SSC | <<locked>> | 92% | 42,670 psi | 66% | 2510 fps | 95.7% |
| Lovex S062 | <<locked>> | 80% | 51,634 psi | 79% | 2503 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 42,612 psi | 66% | 2388 fps | 99.2% |
| Lovex S070 | <<locked>> | 80% | 40,901 psi | 63% | 2375 fps | 98.2% |
| Lovex S071 | <<locked>> | 84% | 29,051 psi | 45% | 2152 fps | 95.2% |
| Norma 203B | <<locked>> | 80% | 52,025 psi | 80% | 2552 fps | 100% |
| Norma 204 | <<locked>> | 80% | 38,812 psi | 60% | 2372 fps | 95.7% |
| Norma MRP | 49 gr | 82% | 33,011 psi | 51% | 2329 fps | 95.4% |
| Norma URP | <<locked>> | 80% | 39,682 psi | 61% | 2392 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 80% | 52,533 psi | 81% | 2575 fps | 100% |
| Ramshot Grand | <<locked>> | 90% | 39,726 psi | 61% | 2464 fps | 95% |
| Ramshot Hunter | <<locked>> | 80% | 38,464 psi | 59% | 2385 fps | 98.3% |
| Ramshot Magnum | <<locked>> | 90% | 35,128 psi | 54% | 2349 fps | 95.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,949 psi | 43% | 1460 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 50,169 psi | 77% | 2520 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 46,992 psi | 72% | 2562 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 39,813 psi | 61% | 2421 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 38,392 psi | 59% | 2431 fps | 99.2% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 32,735 psi | 50% | 2359 fps | 95.1% |
| Rottweil R 902 | <<locked>> | 80% | 53,417 psi | 82% | 2510 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 47,065 psi | 72% | 2467 fps | 100% |
| Rottweil R 904 | <<locked>> | 84% | 40,234 psi | 62% | 2372 fps | 95% |
| Rottweil R 905 | <<locked>> | 84% | 37,666 psi | 58% | 2369 fps | 95.8% |
| Rottweil R 907 | <<locked>> | 80% | 43,816 psi | 67% | 2408 fps | 98.2% |
| Shooters World Long Rifle | <<locked>> | 80% | 42,612 psi | 66% | 2388 fps | 99.2% |
| Shooters World Precision | <<locked>> | 80% | 51,634 psi | 79% | 2503 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 40,901 psi | 63% | 2375 fps | 98.2% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 48,196 psi | 74% | 2516 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 47,921 psi | 74% | 2365 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 41,698 psi | 64% | 2339 fps | 98.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 37,318 psi | 57% | 2365 fps | 95.6% |
| Somchem S355 | <<locked>> | 80% | 47,195 psi | 73% | 2464 fps | 100% |
| Somchem S361 | <<locked>> | 86% | 43,555 psi | 67% | 2411 fps | 95.1% |
| Somchem S365 | <<locked>> | 80% | 36,361 psi | 56% | 2356 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 33,460 psi | 51% | 2251 fps | 95.1% |
| Vihtavuori N135 | <<locked>> | 80% | 53,751 psi | 83% | 2467 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 53,766 psi | 83% | 2484 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 45,078 psi | 69% | 2395 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 41,060 psi | 63% | 2388 fps | 99.6% |
| Vihtavuori N165 | <<locked>> | 86% | 35,230 psi | 54% | 2287 fps | 95.4% |
| Vihtavuori N540 | <<locked>> | 80% | 51,953 psi | 80% | 2484 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 40,495 psi | 62% | 2392 fps | 99.5% |
| Vihtavuori N555 | <<locked>> | 80% | 31,792 psi | 49% | 2264 fps | 98.5% |
| Vihtavuori N560 | 53.8 gr | 90% | 43,758 psi | 67% | 2543 fps | 95.6% |
| Vihtavuori N565 | <<locked>> | 96% | 43,004 psi | 66% | 2526 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 40,016 psi | 62% | 2359 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 42,119 psi | 65% | 2448 fps | 98.4% |
| Winchester StaBALL HD | <<locked>> | 80% | 25,266 psi | 39% | 2188 fps | 98.2% |
| Winchester Supreme 780 | <<locked>> | 86% | 37,376 psi | 58% | 2336 fps | 95.4% |
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 .280 Ackley Improved loaded with the .284 | 180gr | Berger Hybrid Target. Norma MRP delivers the highest muzzle velocity at 2,776 fps; across all powders the maximum-charge window runs from 1,598 fps to 2,776 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 (448 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 180.0 gr projectile in 0.284" calls for a 1:9.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2213, ADI AR 2225 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, Norma MRP, Vihtavuori N560 rank at the top here: for .280 Ackley Improved with the .284 | 180gr | Berger Hybrid Target 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.