Load Specifications
Load data in caliber .280 Ackley Improved with .287 | 175gr | Woodleigh PP SN bullet and 90 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 2700 | <<locked>> | 82% | 56,347 psi | 87% | 2621 fps | 99.6% |
| Accurate 3100 | <<locked>> | 98% | 55,201 psi | 85% | 2674 fps | 100% |
| Accurate 4064 | <<locked>> | 82% | 56,188 psi | 86% | 2595 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 57,464 psi | 88% | 2713 fps | 100% |
| Accurate MAGPRO | <<locked>> | 98% | 57,479 psi | 88% | 2818 fps | 97.9% |
| ADI AR 2208 | <<locked>> | 84% | 55,753 psi | 86% | 2628 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 57,943 psi | 89% | 2762 fps | 99.4% |
| ADI AR 2213 | <<locked>> | 98% | 55,680 psi | 86% | 2766 fps | 98.4% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 38,464 psi | 59% | 2510 fps | 97.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 56,985 psi | 88% | 2651 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 57,043 psi | 88% | 2674 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 57,943 psi | 89% | 2759 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 55,651 psi | 86% | 2733 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 57,551 psi | 89% | 2753 fps | 99.4% |
| Alliant Reloder-22 | <<locked>> | 98% | 55,114 psi | 85% | 2762 fps | 99.3% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 55,695 psi | 86% | 2733 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 48,240 psi | 74% | 2684 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 96% | 55,970 psi | 86% | 2822 fps | 100% |
| Baschieri & Pellagri 109ᴾ | <<locked>> | 100% | 58,059 psi | 89% | 2730 fps | 96% |
| Bofors RP15ᴾ | <<locked>> | 100% | 53,954 psi | 83% | 2743 fps | 99.1% |
| Bofors RP3 | <<locked>> | 84% | 57,812 psi | 89% | 2664 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 44,106 psi | 68% | 2615 fps | 96.8% |
| Bofors RP5 | <<locked>> | 98% | 55,114 psi | 85% | 2762 fps | 99.3% |
| Bofors RP7 | <<locked>> | 88% | 56,927 psi | 88% | 2664 fps | 99.7% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 47,688 psi | 73% | 2631 fps | 97.7% |
| Hodgdon H380 | <<locked>> | 84% | 58,160 psi | 89% | 2687 fps | 100% |
| Hodgdon H414 | <<locked>> | 88% | 55,738 psi | 86% | 2717 fps | 99.9% |
| Hodgdon H4350 | <<locked>> | 86% | 54,984 psi | 85% | 2671 fps | 99.3% |
| Hodgdon H4831 | <<locked>> | 96% | 55,970 psi | 86% | 2710 fps | 97.9% |
| Hodgdon H4831 SC | <<locked>> | 98% | 58,494 psi | 90% | 2746 fps | 98.2% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 58,276 psi | 90% | 2684 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 47,384 psi | 73% | 2733 fps | 99% |
| Hodgdon Superformance | <<locked>> | 88% | 55,840 psi | 86% | 2753 fps | 99.8% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,796 psi | 57% | 1637 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 58,755 psi | 90% | 2657 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 57,667 psi | 89% | 2651 fps | 99.9% |
| IMR 4350 | <<locked>> | 92% | 58,247 psi | 90% | 2700 fps | 99.8% |
| IMR 4451 Enduron | <<locked>> | 88% | 58,653 psi | 90% | 2690 fps | 99.9% |
| IMR 4831 | <<locked>> | 92% | 57,595 psi | 89% | 2703 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 58,508 psi | 90% | 2697 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 57,058 psi | 88% | 2694 fps | 98.2% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 56,942 psi | 88% | 2795 fps | 98.7% |
| Lovex S062 | <<locked>> | 82% | 55,753 psi | 86% | 2605 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 58,798 psi | 90% | 2680 fps | 100% |
| Lovex S070 | <<locked>> | 90% | 56,797 psi | 87% | 2680 fps | 99.9% |
| Lovex S071ᴾ | <<locked>> | 100% | 49,313 psi | 76% | 2592 fps | 99.8% |
| Norma 203B | <<locked>> | 82% | 56,333 psi | 87% | 2657 fps | 100% |
| Norma 204 | <<locked>> | 90% | 55,303 psi | 85% | 2700 fps | 99% |
| Norma MRP | <<locked>> | 98% | 58,711 psi | 90% | 2838 fps | 100% |
| Norma URP | <<locked>> | 90% | 55,898 psi | 86% | 2697 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 57,261 psi | 88% | 2687 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 57,609 psi | 89% | 2818 fps | 99.1% |
| Ramshot Hunter | <<locked>> | 92% | 58,407 psi | 90% | 2756 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 51,430 psi | 79% | 2697 fps | 99.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,565 psi | 58% | 1677 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 57,798 psi | 89% | 2674 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 54,955 psi | 85% | 2720 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 57,101 psi | 88% | 2733 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 55,564 psi | 85% | 2766 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 47,369 psi | 73% | 2730 fps | 99.6% |
| Rottweil R 902 | <<locked>> | 82% | 57,682 psi | 89% | 2615 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 58,001 psi | 89% | 2664 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 56,057 psi | 86% | 2684 fps | 98.5% |
| Rottweil R 905 | <<locked>> | 96% | 56,797 psi | 87% | 2740 fps | 99.4% |
| Rottweil R 907 | <<locked>> | 88% | 56,927 psi | 88% | 2664 fps | 99.7% |
| Shooters World Long Rifle | <<locked>> | 90% | 58,798 psi | 90% | 2680 fps | 100% |
| Shooters World Precision | <<locked>> | 82% | 55,753 psi | 86% | 2605 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 56,797 psi | 87% | 2680 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 55,869 psi | 86% | 2671 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 58,479 psi | 90% | 2543 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 58,465 psi | 90% | 2641 fps | 99.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 56,333 psi | 87% | 2736 fps | 99.4% |
| Somchem S355 | <<locked>> | 86% | 57,899 psi | 89% | 2661 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 57,551 psi | 89% | 2677 fps | 98% |
| Somchem S365 | <<locked>> | 92% | 55,724 psi | 86% | 2700 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 57,479 psi | 88% | 2717 fps | 99.8% |
| Vihtavuori N135 | <<locked>> | 82% | 58,001 psi | 89% | 2566 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 58,262 psi | 90% | 2585 fps | 100% |
| Vihtavuori N150 | <<locked>> | 86% | 55,434 psi | 85% | 2585 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 57,928 psi | 89% | 2690 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 56,579 psi | 87% | 2690 fps | 99.6% |
| Vihtavuori N540 | <<locked>> | 82% | 56,333 psi | 87% | 2585 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 56,826 psi | 87% | 2694 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 58,392 psi | 90% | 2759 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 58,740 psi | 90% | 2835 fps | 98.6% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 50,531 psi | 78% | 2697 fps | 97.5% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 57,508 psi | 88% | 2654 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 55,738 psi | 86% | 2717 fps | 99.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 51,982 psi | 80% | 2808 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 57,595 psi | 89% | 2713 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 2700 | <<locked>> | 80% | 52,895 psi | 81% | 2569 fps | 99.3% |
| Accurate 3100 | <<locked>> | 80% | 30,240 psi | 47% | 2218 fps | 95.5% |
| Accurate 4064 | <<locked>> | 80% | 52,982 psi | 82% | 2552 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 40,944 psi | 63% | 2457 fps | 99.7% |
| Accurate MAGPRO | <<locked>> | 92% | 46,586 psi | 72% | 2644 fps | 95.6% |
| ADI AR 2208 | <<locked>> | 80% | 49,400 psi | 76% | 2536 fps | 100% |
| ADI AR 2209 | <<locked>> | 84% | 39,247 psi | 60% | 2441 fps | 95.8% |
| ADI AR 2213 | <<locked>> | 90% | 42,772 psi | 66% | 2539 fps | 95.4% |
| ADI AR 2225 | <<locked>> | 96% | 33,910 psi | 52% | 2398 fps | 95.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 50,169 psi | 77% | 2556 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 53,534 psi | 82% | 2621 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 39,566 psi | 61% | 2467 fps | 99.7% |
| Alliant Reloder-17 | <<locked>> | 80% | 44,933 psi | 69% | 2575 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 82% | 36,695 psi | 56% | 2385 fps | 95% |
| Alliant Reloder-22 | <<locked>> | 86% | 36,854 psi | 57% | 2431 fps | 95.3% |
| Alliant Reloder-23 | <<locked>> | 80% | 29,225 psi | 45% | 2247 fps | 98.6% |
| Alliant Reloder-25 | <<locked>> | 84% | 29,037 psi | 45% | 2257 fps | 95.4% |
| Alliant Reloder-26 | 51.3 gr | 80% | 31,328 psi | 48% | 2362 fps | 97.5% |
| Baschieri & Pellagri 109 | <<locked>> | 98% | 54,534 psi | 84% | 2674 fps | 95.2% |
| Bofors RP15 | <<locked>> | 88% | 36,608 psi | 56% | 2425 fps | 95% |
| Bofors RP3 | <<locked>> | 80% | 50,778 psi | 78% | 2569 fps | 100% |
| Bofors RP30 | <<locked>> | 96% | 38,798 psi | 60% | 2507 fps | 95.1% |
| Bofors RP5 | <<locked>> | 86% | 36,854 psi | 57% | 2431 fps | 95.3% |
| Bofors RP7 | <<locked>> | 80% | 44,382 psi | 68% | 2464 fps | 98.2% |
| Hodgdon H1000 | <<locked>> | 94% | 39,088 psi | 60% | 2461 fps | 95% |
| Hodgdon H380 | <<locked>> | 80% | 51,184 psi | 79% | 2589 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 42,844 psi | 66% | 2503 fps | 98.4% |
| Hodgdon H4350 | <<locked>> | 80% | 45,440 psi | 70% | 2516 fps | 97.9% |
| Hodgdon H4831 | <<locked>> | 90% | 45,571 psi | 70% | 2546 fps | 95.7% |
| Hodgdon H4831 SC | <<locked>> | 90% | 44,860 psi | 69% | 2530 fps | 95.4% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 37,246 psi | 57% | 2362 fps | 99.9% |
| Hodgdon Retumbo | <<locked>> | 92% | 36,637 psi | 56% | 2497 fps | 95.6% |
| Hodgdon Superformance | <<locked>> | 80% | 41,626 psi | 64% | 2516 fps | 97.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,586 psi | 42% | 1463 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 51,996 psi | 80% | 2566 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 54,230 psi | 83% | 2602 fps | 99.7% |
| IMR 4350 | <<locked>> | 80% | 40,103 psi | 62% | 2402 fps | 97.3% |
| IMR 4451 Enduron | <<locked>> | 80% | 45,701 psi | 70% | 2487 fps | 98.8% |
| IMR 4831 | <<locked>> | 80% | 39,175 psi | 60% | 2411 fps | 99.5% |
| IMR 4895 | <<locked>> | 80% | 54,911 psi | 84% | 2648 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 88% | 44,614 psi | 69% | 2490 fps | 95.6% |
| IMR 7828 SSC | <<locked>> | 92% | 43,598 psi | 67% | 2569 fps | 95.8% |
| Lovex S062 | <<locked>> | 80% | 52,330 psi | 81% | 2559 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 43,453 psi | 67% | 2444 fps | 99.3% |
| Lovex S070 | <<locked>> | 80% | 41,669 psi | 64% | 2431 fps | 98.3% |
| Lovex S071 | <<locked>> | 84% | 29,733 psi | 46% | 2205 fps | 95.3% |
| Norma 203B | <<locked>> | 80% | 52,910 psi | 81% | 2608 fps | 100% |
| Norma 204 | <<locked>> | 80% | 39,668 psi | 61% | 2428 fps | 95.8% |
| Norma MRP | 51 gr | 82% | 33,678 psi | 52% | 2385 fps | 95.6% |
| Norma URP | <<locked>> | 80% | 40,495 psi | 62% | 2448 fps | 99.6% |
| Ramshot Big Game | <<locked>> | 80% | 53,461 psi | 82% | 2635 fps | 100% |
| Ramshot Grand | <<locked>> | 90% | 40,364 psi | 62% | 2516 fps | 95.2% |
| Ramshot Hunter | <<locked>> | 80% | 39,291 psi | 60% | 2444 fps | 98.3% |
| Ramshot Magnum | <<locked>> | 90% | 36,042 psi | 55% | 2408 fps | 95.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,123 psi | 43% | 1496 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 50,778 psi | 78% | 2572 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 47,732 psi | 73% | 2618 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 40,712 psi | 63% | 2477 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 39,131 psi | 60% | 2484 fps | 99.2% |
| ReloadSwiss RS 76 | <<locked>> | 90% | 33,475 psi | 51% | 2415 fps | 95.3% |
| Rottweil R 902 | <<locked>> | 80% | 54,143 psi | 83% | 2569 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 47,979 psi | 74% | 2523 fps | 100% |
| Rottweil R 904 | <<locked>> | 84% | 40,828 psi | 63% | 2425 fps | 95.1% |
| Rottweil R 905 | <<locked>> | 84% | 38,290 psi | 59% | 2421 fps | 95.8% |
| Rottweil R 907 | <<locked>> | 80% | 44,382 psi | 68% | 2464 fps | 98.2% |
| Shooters World Long Rifle | <<locked>> | 80% | 43,453 psi | 67% | 2444 fps | 99.3% |
| Shooters World Precision | <<locked>> | 80% | 52,330 psi | 81% | 2559 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 41,669 psi | 64% | 2431 fps | 98.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 49,182 psi | 76% | 2579 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 48,675 psi | 75% | 2418 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 42,366 psi | 65% | 2395 fps | 98.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 37,942 psi | 58% | 2418 fps | 95.7% |
| Somchem S355 | <<locked>> | 80% | 48,095 psi | 74% | 2523 fps | 100% |
| Somchem S361 | <<locked>> | 86% | 44,251 psi | 68% | 2467 fps | 95.2% |
| Somchem S365 | <<locked>> | 80% | 37,188 psi | 57% | 2411 fps | 100% |
| Somchem S385 | <<locked>> | 80% | 34,098 psi | 52% | 2303 fps | 95.2% |
| Vihtavuori N135 | <<locked>> | 80% | 54,621 psi | 84% | 2523 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 54,679 psi | 84% | 2543 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 45,905 psi | 71% | 2451 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 41,858 psi | 64% | 2444 fps | 99.7% |
| Vihtavuori N165 | <<locked>> | 86% | 35,926 psi | 55% | 2339 fps | 95.5% |
| Vihtavuori N540 | <<locked>> | 80% | 52,968 psi | 81% | 2543 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 41,379 psi | 64% | 2451 fps | 99.5% |
| Vihtavuori N555 | <<locked>> | 80% | 32,605 psi | 50% | 2320 fps | 98.6% |
| Vihtavuori N560 | 56 gr | 90% | 44,686 psi | 69% | 2605 fps | 95.7% |
| Vihtavuori N565 | <<locked>> | 94% | 41,191 psi | 63% | 2530 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 40,683 psi | 63% | 2415 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 42,844 psi | 66% | 2503 fps | 98.4% |
| Winchester StaBALL HD | <<locked>> | 80% | 25,846 psi | 40% | 2244 fps | 98.3% |
| Winchester Supreme 780 | <<locked>> | 86% | 38,189 psi | 59% | 2392 fps | 95.6% |
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 96 powders for .280 Ackley Improved loaded with the .287 | 175gr | Woodleigh PP SN. Norma MRP delivers the highest muzzle velocity at 2,838 fps; across all powders the maximum-charge window runs from 1,637 fps to 2,838 fps. ADI AR 2217 gives the best case fill at 100 %, and 96 of the 96 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 52–90 %, leaving at least 10 % headroom. The 175.0 gr projectile in 0.287" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. ADI AR 2217, ADI AR 2225, 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. Alliant Reloder-26, Norma MRP, Vihtavuori N560 rank at the top here: for .280 Ackley Improved with the .287 | 175gr | Woodleigh PP SN they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, IMR 8133 Enduron, ReloadSwiss RS 80, Vihtavuori N170 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.