Load Specifications
Load data in caliber .280 Ackley Improved with .284 | 165gr | Geco SOFTPOINT bullet and 91 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.
A valid access license is required to use the Personalized Load Calculator.
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% | 56,202 psi | 86% | 2707 fps | 99.4% |
| Accurate 3100 | <<locked>> | 98% | 55,361 psi | 85% | 2762 fps | 100% |
| Accurate 4064 | <<locked>> | 82% | 56,159 psi | 86% | 2687 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 57,319 psi | 88% | 2802 fps | 100% |
| Accurate MAGPRO | <<locked>> | 98% | 57,464 psi | 88% | 2907 fps | 97.6% |
| ADI AR 2208 | <<locked>> | 84% | 55,666 psi | 86% | 2717 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 57,986 psi | 89% | 2851 fps | 99.2% |
| ADI AR 2213 | <<locked>> | 98% | 55,463 psi | 85% | 2848 fps | 98.1% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 38,421 psi | 59% | 2582 fps | 97.1% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 58,030 psi | 89% | 2844 fps | 99.2% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 58,030 psi | 89% | 2844 fps | 99.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 56,797 psi | 87% | 2740 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 56,884 psi | 88% | 2759 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 57,783 psi | 89% | 2851 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 86% | 55,434 psi | 85% | 2822 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 57,232 psi | 88% | 2838 fps | 99.2% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 58,740 psi | 90% | 2900 fps | 99.4% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 55,840 psi | 86% | 2822 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 48,254 psi | 74% | 2769 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 96% | 56,028 psi | 86% | 2910 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 53,737 psi | 83% | 2825 fps | 98.8% |
| Bofors RP3 | <<locked>> | 84% | 57,740 psi | 89% | 2756 fps | 100% |
| Bofors RP30ᴾ | <<locked>> | 100% | 44,048 psi | 68% | 2690 fps | 96.3% |
| Bofors RP5ᴾ | <<locked>> | 100% | 58,740 psi | 90% | 2900 fps | 99.4% |
| Bofors RP7 | <<locked>> | 88% | 56,739 psi | 87% | 2749 fps | 99.6% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 47,601 psi | 73% | 2710 fps | 97.3% |
| Hodgdon H380 | <<locked>> | 84% | 58,001 psi | 89% | 2776 fps | 100% |
| Hodgdon H414 | <<locked>> | 88% | 55,550 psi | 85% | 2802 fps | 99.8% |
| Hodgdon H4350 | <<locked>> | 88% | 58,450 psi | 90% | 2812 fps | 99.4% |
| Hodgdon H4831 | <<locked>> | 96% | 55,782 psi | 86% | 2795 fps | 97.5% |
| Hodgdon H4831 SC | <<locked>> | 98% | 58,233 psi | 90% | 2831 fps | 97.9% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 58,378 psi | 90% | 2779 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 47,326 psi | 73% | 2815 fps | 98.6% |
| Hodgdon Superformance | <<locked>> | 88% | 55,680 psi | 86% | 2838 fps | 99.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,738 psi | 57% | 1703 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 58,653 psi | 90% | 2746 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 57,508 psi | 88% | 2736 fps | 99.8% |
| IMR 4350 | <<locked>> | 92% | 57,943 psi | 89% | 2785 fps | 99.7% |
| IMR 4451 Enduron | <<locked>> | 88% | 58,407 psi | 90% | 2776 fps | 99.8% |
| IMR 4831 | <<locked>> | 92% | 57,624 psi | 89% | 2792 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 58,349 psi | 90% | 2785 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 57,072 psi | 88% | 2779 fps | 97.9% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 56,826 psi | 87% | 2884 fps | 98.4% |
| Lovex S062 | <<locked>> | 82% | 55,492 psi | 85% | 2690 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 58,784 psi | 90% | 2772 fps | 100% |
| Lovex S070 | <<locked>> | 90% | 56,724 psi | 87% | 2766 fps | 99.8% |
| Lovex S071ᴾ | <<locked>> | 100% | 49,153 psi | 76% | 2671 fps | 99.6% |
| Norma 203B | <<locked>> | 82% | 56,188 psi | 86% | 2746 fps | 100% |
| Norma 204 | <<locked>> | 90% | 55,230 psi | 85% | 2785 fps | 98.8% |
| Norma MRP | <<locked>> | 98% | 58,508 psi | 90% | 2927 fps | 99.9% |
| Norma URP | <<locked>> | 90% | 55,753 psi | 86% | 2785 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 57,014 psi | 88% | 2772 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 57,609 psi | 89% | 2904 fps | 98.8% |
| Ramshot Hunter | <<locked>> | 92% | 58,131 psi | 89% | 2841 fps | 100% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 51,605 psi | 79% | 2779 fps | 99.1% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,478 psi | 58% | 1742 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 57,841 psi | 89% | 2766 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 54,897 psi | 84% | 2808 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 57,203 psi | 88% | 2825 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 90% | 55,550 psi | 85% | 2854 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 47,398 psi | 73% | 2812 fps | 99.4% |
| Rottweil R 902 | <<locked>> | 82% | 57,479 psi | 88% | 2703 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 57,899 psi | 89% | 2753 fps | 100% |
| Rottweil R 904 | <<locked>> | 94% | 55,999 psi | 86% | 2769 fps | 98.2% |
| Rottweil R 905 | <<locked>> | 96% | 56,797 psi | 87% | 2828 fps | 99.2% |
| Rottweil R 907 | <<locked>> | 88% | 56,739 psi | 87% | 2749 fps | 99.6% |
| Shooters World Long Rifle | <<locked>> | 90% | 58,784 psi | 90% | 2772 fps | 100% |
| Shooters World Precision | <<locked>> | 82% | 55,492 psi | 85% | 2690 fps | 100% |
| Shooters World SW4350 | <<locked>> | 90% | 56,724 psi | 87% | 2766 fps | 99.8% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 55,941 psi | 86% | 2762 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 58,349 psi | 90% | 2631 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 58,276 psi | 90% | 2730 fps | 99.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 56,318 psi | 87% | 2822 fps | 99.2% |
| Somchem S355 | <<locked>> | 86% | 57,537 psi | 89% | 2746 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 57,551 psi | 89% | 2762 fps | 97.7% |
| Somchem S365 | <<locked>> | 92% | 55,434 psi | 85% | 2785 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 57,363 psi | 88% | 2802 fps | 99.6% |
| Vihtavuori N135 | <<locked>> | 82% | 57,885 psi | 89% | 2654 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 58,146 psi | 89% | 2677 fps | 100% |
| Vihtavuori N150 | <<locked>> | 86% | 55,390 psi | 85% | 2674 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 57,798 psi | 89% | 2779 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 56,594 psi | 87% | 2779 fps | 99.4% |
| Vihtavuori N540 | <<locked>> | 82% | 56,101 psi | 86% | 2671 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 56,797 psi | 87% | 2782 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 58,349 psi | 90% | 2848 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 58,508 psi | 90% | 2920 fps | 98.3% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 50,328 psi | 77% | 2776 fps | 97% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 57,435 psi | 88% | 2743 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 55,550 psi | 85% | 2802 fps | 99.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 52,011 psi | 80% | 2897 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 57,566 psi | 89% | 2799 fps | 99.1% |
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% | 52,663 psi | 81% | 2651 fps | 99% |
| Accurate 3100 | <<locked>> | 80% | 30,211 psi | 46% | 2287 fps | 95% |
| Accurate 4064 | <<locked>> | 80% | 52,808 psi | 81% | 2641 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 40,872 psi | 63% | 2536 fps | 99.5% |
| Accurate MAGPRO | <<locked>> | 92% | 46,717 psi | 72% | 2726 fps | 95.1% |
| ADI AR 2208 | <<locked>> | 80% | 49,313 psi | 76% | 2618 fps | 100% |
| ADI AR 2209 | <<locked>> | 84% | 39,247 psi | 60% | 2520 fps | 95.3% |
| ADI AR 2213 | <<locked>> | 92% | 45,585 psi | 70% | 2677 fps | 95.8% |
| ADI AR 2225 | <<locked>> | 96% | 33,881 psi | 52% | 2464 fps | 95% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 39,508 psi | 61% | 2520 fps | 95.5% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 39,508 psi | 61% | 2520 fps | 95.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 50,009 psi | 77% | 2641 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 53,534 psi | 82% | 2713 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 39,436 psi | 61% | 2543 fps | 99.5% |
| Alliant Reloder-17 | <<locked>> | 80% | 44,947 psi | 69% | 2657 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 84% | 39,117 psi | 60% | 2516 fps | 95.4% |
| Alliant Reloder-22 | <<locked>> | 88% | 39,320 psi | 60% | 2562 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 80% | 29,109 psi | 45% | 2316 fps | 98.2% |
| Alliant Reloder-25 | <<locked>> | 86% | 30,850 psi | 47% | 2379 fps | 95.8% |
| Alliant Reloder-26 | 53.6 gr | 80% | 31,198 psi | 48% | 2428 fps | 96.9% |
| Bofors RP15 | <<locked>> | 90% | 38,986 psi | 60% | 2552 fps | 95.3% |
| Bofors RP3 | <<locked>> | 80% | 50,705 psi | 78% | 2657 fps | 100% |
| Bofors RP30 | <<locked>> | 98% | 41,336 psi | 64% | 2638 fps | 95.5% |
| Bofors RP5 | <<locked>> | 88% | 39,320 psi | 60% | 2562 fps | 95.6% |
| Bofors RP7 | <<locked>> | 80% | 44,222 psi | 68% | 2539 fps | 97.8% |
| Hodgdon H1000 | <<locked>> | 96% | 41,669 psi | 64% | 2592 fps | 95.5% |
| Hodgdon H380 | <<locked>> | 80% | 50,778 psi | 78% | 2671 fps | 100% |
| Hodgdon H414 | <<locked>> | 80% | 42,685 psi | 66% | 2582 fps | 98% |
| Hodgdon H4350 | <<locked>> | 80% | 45,382 psi | 70% | 2595 fps | 97.5% |
| Hodgdon H4831 | <<locked>> | 90% | 45,600 psi | 70% | 2625 fps | 95.2% |
| Hodgdon H4831 SC | <<locked>> | 92% | 47,819 psi | 74% | 2664 fps | 95.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 36,927 psi | 57% | 2434 fps | 99.8% |
| Hodgdon Retumbo | <<locked>> | 94% | 38,899 psi | 60% | 2628 fps | 96% |
| Hodgdon Superformance | <<locked>> | 80% | 41,582 psi | 64% | 2595 fps | 97.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,499 psi | 42% | 1519 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 51,851 psi | 80% | 2651 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 53,882 psi | 83% | 2684 fps | 99.6% |
| IMR 4350 | <<locked>> | 80% | 39,900 psi | 61% | 2474 fps | 96.8% |
| IMR 4451 Enduron | <<locked>> | 80% | 45,759 psi | 70% | 2572 fps | 98.5% |
| IMR 4831 | <<locked>> | 80% | 38,972 psi | 60% | 2487 fps | 99.2% |
| IMR 4895 | <<locked>> | 80% | 54,940 psi | 85% | 2736 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 88% | 44,382 psi | 68% | 2566 fps | 95% |
| IMR 7828 SSC | <<locked>> | 92% | 43,555 psi | 67% | 2648 fps | 95.3% |
| Lovex S062 | <<locked>> | 80% | 52,214 psi | 80% | 2644 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 43,308 psi | 67% | 2523 fps | 99.1% |
| Lovex S070 | <<locked>> | 80% | 41,481 psi | 64% | 2507 fps | 97.9% |
| Lovex S071 | <<locked>> | 86% | 31,560 psi | 49% | 2320 fps | 95.6% |
| Norma 203B | <<locked>> | 80% | 52,895 psi | 81% | 2700 fps | 100% |
| Norma 204 | <<locked>> | 80% | 39,479 psi | 61% | 2503 fps | 95.3% |
| Norma MRP | 54.6 gr | 84% | 35,940 psi | 55% | 2513 fps | 96% |
| Norma URP | <<locked>> | 80% | 40,292 psi | 62% | 2526 fps | 99.3% |
| Ramshot Big Game | <<locked>> | 80% | 53,374 psi | 82% | 2723 fps | 100% |
| Ramshot Grand | <<locked>> | 92% | 43,221 psi | 66% | 2654 fps | 95.6% |
| Ramshot Hunter | <<locked>> | 80% | 39,160 psi | 60% | 2516 fps | 97.9% |
| Ramshot Magnum | <<locked>> | 90% | 35,868 psi | 55% | 2477 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,007 psi | 43% | 1555 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 50,807 psi | 78% | 2661 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 47,688 psi | 73% | 2703 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 40,451 psi | 62% | 2549 fps | 99.2% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 39,044 psi | 60% | 2562 fps | 98.9% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 35,737 psi | 55% | 2546 fps | 95.8% |
| Rottweil R 902 | <<locked>> | 80% | 54,056 psi | 83% | 2657 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 47,718 psi | 73% | 2605 fps | 100% |
| Rottweil R 904 | <<locked>> | 86% | 43,250 psi | 67% | 2549 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 84% | 38,305 psi | 59% | 2497 fps | 95.3% |
| Rottweil R 907 | <<locked>> | 80% | 44,222 psi | 68% | 2539 fps | 97.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 43,308 psi | 67% | 2523 fps | 99.1% |
| Shooters World Precision | <<locked>> | 80% | 52,214 psi | 80% | 2644 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 41,481 psi | 64% | 2507 fps | 97.9% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 48,979 psi | 75% | 2661 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 48,704 psi | 75% | 2503 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 42,351 psi | 65% | 2470 fps | 98% |
| SNPE Vectan Tubal 8000 | <<locked>> | 84% | 37,956 psi | 58% | 2493 fps | 95.2% |
| Somchem S355 | <<locked>> | 80% | 47,935 psi | 74% | 2605 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 47,224 psi | 73% | 2598 fps | 95.6% |
| Somchem S365 | <<locked>> | 80% | 36,970 psi | 57% | 2487 fps | 100% |
| Somchem S385 | <<locked>> | 82% | 36,434 psi | 56% | 2431 fps | 95.6% |
| Vihtavuori N135 | <<locked>> | 80% | 54,650 psi | 84% | 2615 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 54,491 psi | 84% | 2628 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 45,730 psi | 70% | 2533 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 41,829 psi | 64% | 2526 fps | 99.5% |
| Vihtavuori N165 | <<locked>> | 88% | 38,145 psi | 59% | 2464 fps | 95.8% |
| Vihtavuori N540 | <<locked>> | 80% | 52,576 psi | 81% | 2625 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 41,060 psi | 63% | 2523 fps | 99.3% |
| Vihtavuori N555 | <<locked>> | 80% | 32,445 psi | 50% | 2388 fps | 98.2% |
| Vihtavuori N560 | 58.5 gr | 90% | 44,556 psi | 69% | 2680 fps | 95.2% |
| Vihtavuori N565 | <<locked>> | 96% | 44,063 psi | 68% | 2661 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 40,756 psi | 63% | 2493 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 42,685 psi | 66% | 2582 fps | 98% |
| Winchester StaBALL HD | <<locked>> | 80% | 25,744 psi | 40% | 2303 fps | 97.6% |
| Winchester Supreme 780 | <<locked>> | 86% | 37,956 psi | 58% | 2464 fps | 95% |
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 91 powders for .280 Ackley Improved loaded with the .284 | 165gr | Geco SOFTPOINT. Norma MRP delivers the highest muzzle velocity at 2,927 fps; across all powders the maximum-charge window runs from 1,703 fps to 2,927 fps. ADI AR 2225 gives the best case fill at 100 %, and 91 of the 91 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 165.0 gr projectile in 0.284" calls for a 1:13.5 twist; slower twists will usually not stabilise this weight. ADI AR 2225, Alliant Reloder-22, 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 .284 | 165gr | Geco SOFTPOINT 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.