Load Specifications
Bullet:.284 | 150gr | Hornady CX
Bullet Manufacturer:Hornady
Bullet Weight:150 gr
Bullet Diameter:0.284"
Bullet Length:<<locked>>
Caliber:.280 Ackley Improved load data
Case Length (l3):2.54"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:74 Grains of Water
Primer Size:Large Rifle (LR)
Barrel Length:24"
Max. allowed Pressure:65,000 psi
Recommended Twist Rate:1:9.0
Load data in caliber .280 Ackley Improved with .284 | 150gr | Hornady CX bullet and 105 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Alliant Reloder-17 and ReloadSwiss RS 60.
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 2015 | <<locked>> | 82% | 57,000 psi | 88% | 2730 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 56,231 psi | 87% | 2759 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 57,885 psi | 89% | 2828 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 58,697 psi | 90% | 2831 fps | 98.7% |
| Accurate 3100ᴾ | <<locked>> | 100% | 47,253 psi | 73% | 2743 fps | 98.4% |
| Accurate 4064 | <<locked>> | 88% | 56,449 psi | 87% | 2812 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 57,203 psi | 88% | 2913 fps | 100% |
| ADI AR 2206H | <<locked>> | 84% | 56,376 psi | 87% | 2844 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 57,479 psi | 88% | 2848 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 55,013 psi | 85% | 2900 fps | 97.5% |
| ADI Benchmark 8208 | <<locked>> | 84% | 58,798 psi | 90% | 2841 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 56,724 psi | 87% | 2759 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 56,855 psi | 87% | 2976 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 57,943 psi | 89% | 2871 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 58,436 psi | 90% | 2894 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 98% | 58,262 psi | 90% | 2972 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 92% | 55,883 psi | 86% | 2949 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 54,012 psi | 83% | 2887 fps | 97.5% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 47,674 psi | 73% | 2825 fps | 96.3% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 44,802 psi | 69% | 2772 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 39,117 psi | 60% | 2677 fps | 97.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 50,792 psi | 78% | 2953 fps | 99.9% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 56,478 psi | 87% | 2867 fps | 100% |
| Bofors RP3 | <<locked>> | 90% | 58,798 psi | 90% | 2887 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 47,674 psi | 73% | 2825 fps | 96.3% |
| Bofors RP7 | <<locked>> | 94% | 58,566 psi | 90% | 2871 fps | 98.9% |
| Hodgdon Benchmark | <<locked>> | 82% | 56,507 psi | 87% | 2769 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 54,752 psi | 84% | 2822 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 55,782 psi | 86% | 2854 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 94% | 56,275 psi | 87% | 2917 fps | 99.1% |
| Hodgdon H4350 | <<locked>> | 92% | 56,420 psi | 87% | 2877 fps | 98.1% |
| Hodgdon H4895 | <<locked>> | 84% | 56,985 psi | 88% | 2854 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 58,262 psi | 90% | 2890 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 57,261 psi | 88% | 2894 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 56,811 psi | 87% | 2959 fps | 99% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,868 psi | 55% | 1739 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 58,291 psi | 90% | 2858 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 57,609 psi | 89% | 2831 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 57,014 psi | 88% | 2831 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 56,449 psi | 87% | 2815 fps | 99% |
| IMR 4350 | <<locked>> | 96% | 55,593 psi | 86% | 2848 fps | 98.5% |
| IMR 4451 Enduron | <<locked>> | 92% | 56,855 psi | 87% | 2848 fps | 99% |
| IMR 4831 | <<locked>> | 98% | 57,682 psi | 89% | 2907 fps | 100% |
| IMR 4895 | <<locked>> | 86% | 56,434 psi | 87% | 2871 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 58,798 psi | 90% | 2841 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 56,594 psi | 87% | 2818 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 55,535 psi | 85% | 2772 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 56,826 psi | 87% | 2822 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 56,376 psi | 87% | 2841 fps | 99.7% |
| Lovex S070 | <<locked>> | 96% | 57,493 psi | 88% | 2877 fps | 99.3% |
| Lovex S071ᴾ | <<locked>> | 100% | 39,117 psi | 60% | 2592 fps | 96.6% |
| Norma 201 | <<locked>> | 86% | 58,537 psi | 90% | 2838 fps | 100% |
| Norma 202 | <<locked>> | 84% | 55,695 psi | 86% | 2785 fps | 100% |
| Norma 203B | <<locked>> | 88% | 57,624 psi | 89% | 2881 fps | 100% |
| Norma 204 | <<locked>> | 96% | 56,376 psi | 87% | 2900 fps | 97.7% |
| Norma MRPᴾ | <<locked>> | 100% | 50,227 psi | 77% | 2907 fps | 98.2% |
| Norma URP | <<locked>> | 96% | 56,028 psi | 86% | 2904 fps | 100% |
| Ramshot Big Game | <<locked>> | 88% | 58,697 psi | 90% | 2910 fps | 100% |
| Ramshot Hunter | <<locked>> | 98% | 58,682 psi | 90% | 2959 fps | 99.7% |
| Ramshot TAC | <<locked>> | 82% | 55,463 psi | 85% | 2822 fps | 99.7% |
| Ramshot Wild Boar | <<locked>> | 82% | 55,347 psi | 85% | 2835 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,477 psi | 56% | 1781 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 56,130 psi | 86% | 2841 fps | 99.3% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 55,767 psi | 86% | 2910 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 55,579 psi | 86% | 2946 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 57,290 psi | 88% | 2943 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 56,086 psi | 86% | 2972 fps | 100% |
| Rottweil R 901 | <<locked>> | 82% | 55,651 psi | 86% | 2762 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 55,593 psi | 86% | 2789 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 58,639 psi | 90% | 2877 fps | 100% |
| Rottweil R 904ᴾ | <<locked>> | 100% | 56,869 psi | 87% | 2874 fps | 96.8% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 53,098 psi | 82% | 2871 fps | 97.5% |
| Rottweil R 907 | <<locked>> | 94% | 58,566 psi | 90% | 2871 fps | 98.9% |
| Shooters World Long Rifle | <<locked>> | 94% | 56,376 psi | 87% | 2841 fps | 99.7% |
| Shooters World Match Rifle | <<locked>> | 84% | 56,594 psi | 87% | 2818 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 56,826 psi | 87% | 2822 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 57,493 psi | 88% | 2877 fps | 99.3% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 57,130 psi | 88% | 2894 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 57,667 psi | 89% | 2851 fps | 99.9% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 58,595 psi | 90% | 2871 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 56,304 psi | 87% | 2723 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 56,768 psi | 87% | 2720 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 56,521 psi | 87% | 2795 fps | 99% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 52,620 psi | 81% | 2867 fps | 97.4% |
| Somchem S335 | <<locked>> | 84% | 55,825 psi | 86% | 2723 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 57,537 psi | 89% | 2838 fps | 100% |
| Somchem S355 | <<locked>> | 90% | 55,100 psi | 85% | 2825 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 58,624 psi | 90% | 2953 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 53,867 psi | 83% | 2851 fps | 98.3% |
| Vihtavuori N133 | <<locked>> | 84% | 56,768 psi | 87% | 2707 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 55,898 psi | 86% | 2749 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 56,304 psi | 87% | 2766 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 56,608 psi | 87% | 2802 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 58,552 psi | 90% | 2897 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 46,166 psi | 71% | 2710 fps | 96.3% |
| Vihtavuori N530 | <<locked>> | 82% | 55,724 psi | 86% | 2792 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 58,001 psi | 89% | 2812 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 57,450 psi | 88% | 2900 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 49,922 psi | 77% | 2848 fps | 99.9% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 58,566 psi | 90% | 2871 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 56,231 psi | 87% | 2841 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 56,275 psi | 87% | 2917 fps | 99.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 40,089 psi | 62% | 2805 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 84% | 54,781 psi | 84% | 2825 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 50,285 psi | 77% | 2785 fps | 96.6% |
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 2015 | <<locked>> | 80% | 53,534 psi | 82% | 2687 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 46,064 psi | 71% | 2615 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 54,128 psi | 83% | 2776 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 44,991 psi | 69% | 2612 fps | 96.2% |
| Accurate 3100 | <<locked>> | 92% | 35,708 psi | 55% | 2516 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 43,613 psi | 67% | 2618 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 32,576 psi | 50% | 2461 fps | 96.2% |
| ADI AR 2206H | <<locked>> | 80% | 49,632 psi | 76% | 2743 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 42,061 psi | 65% | 2592 fps | 99.1% |
| ADI AR 2209 | <<locked>> | 94% | 45,252 psi | 70% | 2730 fps | 95.2% |
| ADI Benchmark 8208 | <<locked>> | 80% | 51,808 psi | 80% | 2743 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 53,098 psi | 82% | 2713 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 45,876 psi | 71% | 2792 fps | 99.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 42,047 psi | 65% | 2615 fps | 99.8% |
| Alliant Reloder-15 | <<locked>> | 80% | 45,194 psi | 70% | 2684 fps | 99.6% |
| Alliant Reloder-16 | <<locked>> | 80% | 32,634 psi | 50% | 2477 fps | 96.3% |
| Alliant Reloder-17 | 48.4 gr | 80% | 36,753 psi | 57% | 2605 fps | 99.1% |
| Alliant Reloder-19 | <<locked>> | 94% | 44,599 psi | 69% | 2720 fps | 95.2% |
| Alliant Reloder-22 | <<locked>> | 98% | 44,469 psi | 68% | 2762 fps | 95.4% |
| Alliant Reloder-23 | <<locked>> | 84% | 26,760 psi | 41% | 2333 fps | 95.1% |
| Alliant Reloder-25 | <<locked>> | 96% | 34,389 psi | 53% | 2556 fps | 95.2% |
| Alliant Reloder-26 | <<locked>> | 88% | 32,764 psi | 50% | 2562 fps | 95.6% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 49,240 psi | 76% | 2753 fps | 99.7% |
| Bofors RP3 | <<locked>> | 80% | 42,018 psi | 65% | 2621 fps | 99.9% |
| Bofors RP5 | <<locked>> | 98% | 44,469 psi | 68% | 2762 fps | 95.4% |
| Bofors RP7 | <<locked>> | 82% | 40,001 psi | 62% | 2546 fps | 95% |
| Hodgdon Benchmark | <<locked>> | 80% | 53,243 psi | 82% | 2723 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 51,213 psi | 79% | 2769 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 42,699 psi | 66% | 2631 fps | 98.5% |
| Hodgdon H414 | <<locked>> | 84% | 40,147 psi | 62% | 2631 fps | 95.8% |
| Hodgdon H4350 | <<locked>> | 84% | 43,410 psi | 67% | 2651 fps | 95.3% |
| Hodgdon H4895 | <<locked>> | 80% | 50,169 psi | 77% | 2749 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 30,037 psi | 46% | 2375 fps | 97.1% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 46,731 psi | 72% | 2733 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 42,163 psi | 65% | 2700 fps | 95.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,643 psi | 41% | 1552 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 48,240 psi | 74% | 2707 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 50,314 psi | 77% | 2733 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 44,193 psi | 68% | 2625 fps | 99.5% |
| IMR 4166 Enduron | <<locked>> | 80% | 46,833 psi | 72% | 2654 fps | 97.4% |
| IMR 4350 | <<locked>> | 86% | 40,509 psi | 62% | 2579 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 80% | 39,117 psi | 60% | 2530 fps | 95.2% |
| IMR 4831 | <<locked>> | 80% | 31,633 psi | 49% | 2421 fps | 95.9% |
| IMR 4895 | <<locked>> | 80% | 46,340 psi | 71% | 2713 fps | 99.9% |
| IMR 8208 XBR | <<locked>> | 80% | 51,808 psi | 80% | 2743 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 49,327 psi | 76% | 2717 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 48,979 psi | 75% | 2671 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 44,164 psi | 68% | 2625 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 36,347 psi | 56% | 2474 fps | 96% |
| Lovex S070 | <<locked>> | 84% | 39,349 psi | 61% | 2559 fps | 95.8% |
| Lovex S071 | <<locked>> | 98% | 36,579 psi | 56% | 2539 fps | 95.8% |
| Norma 201 | <<locked>> | 80% | 48,399 psi | 74% | 2687 fps | 100% |
| Norma 202 | <<locked>> | 80% | 48,921 psi | 75% | 2687 fps | 100% |
| Norma 203B | <<locked>> | 80% | 44,527 psi | 69% | 2671 fps | 99.7% |
| Norma 204 | <<locked>> | 90% | 46,050 psi | 71% | 2726 fps | 95.4% |
| Norma MRP | <<locked>> | 94% | 40,741 psi | 63% | 2720 fps | 95.8% |
| Norma URP | <<locked>> | 80% | 32,909 psi | 51% | 2464 fps | 96.1% |
| Ramshot Big Game | <<locked>> | 80% | 44,570 psi | 69% | 2690 fps | 99.7% |
| Ramshot Hunter | <<locked>> | 84% | 36,666 psi | 56% | 2562 fps | 95.6% |
| Ramshot TAC | <<locked>> | 80% | 51,750 psi | 80% | 2762 fps | 99.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 51,793 psi | 80% | 2779 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,050 psi | 42% | 1591 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 43,076 psi | 66% | 2618 fps | 97.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 48,472 psi | 75% | 2795 fps | 99.8% |
| ReloadSwiss RS 60 | 48.4 gr | 80% | 39,160 psi | 60% | 2667 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 32,387 psi | 50% | 2477 fps | 95.7% |
| ReloadSwiss RS 70 | 50.3 gr | 82% | 34,330 psi | 53% | 2539 fps | 95.7% |
| Rottweil R 901 | <<locked>> | 80% | 52,359 psi | 81% | 2717 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 45,934 psi | 71% | 2638 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 39,494 psi | 61% | 2569 fps | 99.5% |
| Rottweil R 904 | <<locked>> | 96% | 49,893 psi | 77% | 2759 fps | 95.2% |
| Rottweil R 905 | <<locked>> | 94% | 43,410 psi | 67% | 2700 fps | 95.1% |
| Rottweil R 907 | <<locked>> | 82% | 40,001 psi | 62% | 2546 fps | 95% |
| Shooters World Long Rifle | <<locked>> | 80% | 36,347 psi | 56% | 2474 fps | 96% |
| Shooters World Match Rifle | <<locked>> | 80% | 49,327 psi | 76% | 2717 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 44,164 psi | 68% | 2625 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 39,349 psi | 61% | 2559 fps | 95.8% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 40,727 psi | 63% | 2621 fps | 99.3% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 50,401 psi | 78% | 2743 fps | 99.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 48,138 psi | 74% | 2713 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 49,617 psi | 76% | 2631 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 41,626 psi | 64% | 2500 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 38,072 psi | 59% | 2474 fps | 95.1% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 42,989 psi | 66% | 2697 fps | 95% |
| Somchem S335 | <<locked>> | 80% | 49,240 psi | 76% | 2628 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 50,096 psi | 77% | 2730 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 40,132 psi | 62% | 2569 fps | 99.5% |
| Somchem S365 | <<locked>> | 80% | 29,501 psi | 45% | 2418 fps | 98.3% |
| Somchem S385 | <<locked>> | 92% | 41,118 psi | 63% | 2628 fps | 95.4% |
| Vihtavuori N133 | <<locked>> | 80% | 50,154 psi | 77% | 2618 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 46,093 psi | 71% | 2612 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 46,514 psi | 72% | 2625 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 38,276 psi | 59% | 2507 fps | 99.8% |
| Vihtavuori N160 | <<locked>> | 80% | 34,287 psi | 53% | 2467 fps | 96.6% |
| Vihtavuori N165 | <<locked>> | 98% | 43,323 psi | 67% | 2657 fps | 95.6% |
| Vihtavuori N530 | <<locked>> | 80% | 52,083 psi | 80% | 2740 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 44,817 psi | 69% | 2615 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 33,750 psi | 52% | 2464 fps | 96.2% |
| Vihtavuori N555 | <<locked>> | 84% | 29,022 psi | 45% | 2405 fps | 95.3% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 33,765 psi | 52% | 2441 fps | 98.5% |
| Winchester 748 | <<locked>> | 80% | 52,576 psi | 81% | 2792 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 40,147 psi | 62% | 2631 fps | 95.8% |
| Winchester StaBALL HD | <<locked>> | 88% | 26,789 psi | 41% | 2411 fps | 95.8% |
| Winchester StaBALL Match | <<locked>> | 80% | 47,906 psi | 74% | 2717 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 47,065 psi | 72% | 2730 fps | 95.8% |
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 119 powders for .280 Ackley Improved loaded with the .284 | 150gr | Hornady CX. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,976 fps; across all powders the maximum-charge window runs from 1,739 fps to 2,976 fps. Accurate 3100 gives the best case fill at 100 %, and 119 of the 119 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 150.0 gr projectile in 0.284" calls for a 1:9.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate MAGPRO, ADI AR 2209 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, Alliant Reloder-17, ReloadSwiss RS 60 rank at the top here: for .280 Ackley Improved with the .284 | 150gr | Hornady CX they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate MAGPRO, ADI AR 2213, Bofors RP15 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.