Load Specifications
Bullet Manufacturer:Sierra
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:1:11.5
Load data in caliber .280 Ackley Improved with .284 | 150gr | Sierra MatchKing bullet and 104 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-26 and Alliant Reloder-16.
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 2495 | <<locked>> | 84% | 58,276 psi | 90% | 2792 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 55,883 psi | 86% | 2815 fps | 98.7% |
| Accurate 3100ᴾ | <<locked>> | 100% | 53,432 psi | 82% | 2854 fps | 99.5% |
| Accurate 4064 | <<locked>> | 86% | 58,581 psi | 90% | 2848 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 55,811 psi | 86% | 2907 fps | 100% |
| Accurate MAGPROᴾ | <<locked>> | 100% | 55,564 psi | 85% | 2995 fps | 96% |
| ADI AR 2206H | <<locked>> | 82% | 57,406 psi | 88% | 2877 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 58,552 psi | 90% | 2881 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 56,550 psi | 87% | 2946 fps | 98.2% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 54,375 psi | 84% | 2943 fps | 96.7% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 58,189 psi | 90% | 3009 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 56,811 psi | 87% | 2946 fps | 98.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 55,912 psi | 86% | 2854 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 56,057 psi | 86% | 2874 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 56,405 psi | 87% | 2963 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 57,711 psi | 89% | 2986 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 55,999 psi | 86% | 2936 fps | 98.3% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 53,200 psi | 82% | 2936 fps | 97.9% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 50,227 psi | 77% | 2874 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 43,743 psi | 67% | 2795 fps | 98.9% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 57,812 psi | 89% | 3071 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 57,319 psi | 88% | 2894 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 48,588 psi | 75% | 2854 fps | 96.9% |
| Bofors RP3 | <<locked>> | 86% | 56,681 psi | 87% | 2871 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 53,200 psi | 82% | 2936 fps | 97.9% |
| Bofors RP7 | <<locked>> | 90% | 56,115 psi | 86% | 2854 fps | 98.9% |
| Hodgdon H380 | <<locked>> | 86% | 57,130 psi | 88% | 2887 fps | 100% |
| Hodgdon H414 | <<locked>> | 92% | 57,812 psi | 89% | 2956 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 90% | 57,566 psi | 89% | 2917 fps | 98.7% |
| Hodgdon H4831ᴾ | <<locked>> | 100% | 58,392 psi | 90% | 2946 fps | 96.8% |
| Hodgdon H4831 SCᴾ | <<locked>> | 100% | 57,087 psi | 88% | 2927 fps | 96.6% |
| Hodgdon H4895 | <<locked>> | 82% | 58,073 psi | 89% | 2884 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 56,724 psi | 87% | 2884 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 58,392 psi | 90% | 2923 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 58,392 psi | 90% | 2999 fps | 99.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,419 psi | 56% | 1775 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 55,448 psi | 85% | 2835 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 58,044 psi | 89% | 2864 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 57,130 psi | 88% | 2848 fps | 99.3% |
| IMR 4350 | <<locked>> | 94% | 57,101 psi | 88% | 2890 fps | 99.1% |
| IMR 4451 Enduron | <<locked>> | 90% | 57,841 psi | 89% | 2887 fps | 99.4% |
| IMR 4831 | <<locked>> | 94% | 56,043 psi | 86% | 2897 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 57,479 psi | 88% | 2904 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 55,999 psi | 86% | 2874 fps | 96.5% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 51,808 psi | 80% | 2910 fps | 96.2% |
| Lovex D073.6 | <<locked>> | 82% | 57,914 psi | 89% | 2848 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 56,057 psi | 86% | 2799 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 58,189 psi | 90% | 2854 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 57,711 psi | 89% | 2877 fps | 99.9% |
| Lovex S070 | <<locked>> | 92% | 55,535 psi | 85% | 2867 fps | 99.3% |
| Lovex S071ᴾ | <<locked>> | 100% | 44,295 psi | 68% | 2703 fps | 98.3% |
| Norma 201 | <<locked>> | 82% | 56,130 psi | 86% | 2818 fps | 100% |
| Norma 202 | <<locked>> | 82% | 56,913 psi | 88% | 2815 fps | 100% |
| Norma 203B | <<locked>> | 84% | 55,347 psi | 85% | 2861 fps | 100% |
| Norma 204 | <<locked>> | 94% | 58,044 psi | 89% | 2943 fps | 98.3% |
| Norma MRPᴾ | <<locked>> | 100% | 56,550 psi | 87% | 3022 fps | 99.4% |
| Norma URP | <<locked>> | 94% | 58,088 psi | 89% | 2946 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 56,173 psi | 86% | 2887 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 51,822 psi | 80% | 2923 fps | 96.6% |
| Ramshot Hunter | <<locked>> | 94% | 56,811 psi | 87% | 2946 fps | 99.8% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 46,325 psi | 71% | 2799 fps | 97.1% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,086 psi | 57% | 1818 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 57,087 psi | 88% | 2874 fps | 99.6% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 57,101 psi | 88% | 2943 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 57,203 psi | 88% | 2976 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 55,608 psi | 86% | 2930 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 58,001 psi | 89% | 3015 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 42,685 psi | 66% | 2808 fps | 97% |
| Rottweil R 902 | <<locked>> | 84% | 56,898 psi | 88% | 2822 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 56,826 psi | 87% | 2867 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 58,363 psi | 90% | 2917 fps | 97.5% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 58,798 psi | 90% | 2976 fps | 98.7% |
| Rottweil R 907 | <<locked>> | 90% | 56,115 psi | 86% | 2854 fps | 98.9% |
| Shooters World Long Rifle | <<locked>> | 92% | 57,711 psi | 89% | 2877 fps | 99.9% |
| Shooters World Match Rifle | <<locked>> | 82% | 57,914 psi | 89% | 2848 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 58,189 psi | 90% | 2854 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 55,535 psi | 85% | 2867 fps | 99.3% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 58,595 psi | 90% | 2927 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 55,753 psi | 86% | 2848 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 56,753 psi | 87% | 2746 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 57,682 psi | 89% | 2749 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 57,696 psi | 89% | 2835 fps | 99.4% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 58,276 psi | 90% | 2969 fps | 98.7% |
| Somchem S335 | <<locked>> | 82% | 56,579 psi | 87% | 2746 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 58,349 psi | 90% | 2867 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 56,666 psi | 87% | 2861 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 56,637 psi | 87% | 2858 fps | 96.4% |
| Somchem S365 | <<locked>> | 96% | 57,276 psi | 88% | 2943 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 55,738 psi | 86% | 2897 fps | 98.9% |
| Vihtavuori N133 | <<locked>> | 82% | 57,290 psi | 88% | 2730 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 57,101 psi | 88% | 2776 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 57,522 psi | 88% | 2795 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 58,059 psi | 89% | 2835 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 56,637 psi | 87% | 2887 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 51,547 psi | 79% | 2815 fps | 97.9% |
| Vihtavuori N540 | <<locked>> | 84% | 55,666 psi | 86% | 2792 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 55,637 psi | 86% | 2890 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 56,202 psi | 86% | 2949 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 56,884 psi | 88% | 3012 fps | 96.9% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 56,231 psi | 87% | 2851 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 58,102 psi | 89% | 2963 fps | 99.5% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 45,252 psi | 70% | 2927 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 55,869 psi | 86% | 2854 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 56,014 psi | 86% | 2894 fps | 98.1% |
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 2495 | <<locked>> | 80% | 51,285 psi | 79% | 2697 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 48,965 psi | 75% | 2703 fps | 97.6% |
| Accurate 3100 | <<locked>> | 88% | 35,563 psi | 55% | 2520 fps | 95.8% |
| Accurate 4064 | <<locked>> | 80% | 48,573 psi | 75% | 2703 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 36,999 psi | 57% | 2569 fps | 98% |
| Accurate MAGPRO | <<locked>> | 98% | 51,750 psi | 80% | 2930 fps | 95.1% |
| ADI AR 2206H | <<locked>> | 80% | 54,012 psi | 83% | 2825 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 45,803 psi | 70% | 2677 fps | 99.7% |
| ADI AR 2209 | <<locked>> | 90% | 43,598 psi | 67% | 2717 fps | 95.3% |
| ADI AR 2213 | <<locked>> | 98% | 50,691 psi | 78% | 2877 fps | 95.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 50,604 psi | 78% | 2890 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 43,700 psi | 67% | 2717 fps | 95.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 46,412 psi | 71% | 2707 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 49,545 psi | 76% | 2772 fps | 100% |
| Alliant Reloder-16 | 48.1 gr | 80% | 36,100 psi | 56% | 2579 fps | 98% |
| Alliant Reloder-17 | <<locked>> | 80% | 40,843 psi | 63% | 2703 fps | 99.9% |
| Alliant Reloder-19 | <<locked>> | 90% | 43,192 psi | 66% | 2707 fps | 95.4% |
| Alliant Reloder-22 | <<locked>> | 94% | 43,424 psi | 67% | 2756 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 80% | 26,469 psi | 41% | 2329 fps | 95.5% |
| Alliant Reloder-25 | <<locked>> | 92% | 34,026 psi | 52% | 2562 fps | 95.7% |
| Alliant Reloder-26 | 55.7 gr | 84% | 32,285 psi | 50% | 2559 fps | 95.9% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 53,737 psi | 83% | 2841 fps | 100% |
| Bofors RP15 | <<locked>> | 96% | 42,815 psi | 66% | 2743 fps | 95.2% |
| Bofors RP3 | <<locked>> | 80% | 46,601 psi | 72% | 2713 fps | 100% |
| Bofors RP5 | <<locked>> | 94% | 43,424 psi | 67% | 2756 fps | 95.6% |
| Bofors RP7 | <<locked>> | 80% | 40,944 psi | 63% | 2582 fps | 95.8% |
| Hodgdon H380 | <<locked>> | 80% | 46,905 psi | 72% | 2720 fps | 99.4% |
| Hodgdon H414 | <<locked>> | 80% | 38,798 psi | 60% | 2608 fps | 95.8% |
| Hodgdon H4350 | <<locked>> | 80% | 41,872 psi | 64% | 2635 fps | 95.3% |
| Hodgdon H4831 | <<locked>> | 96% | 51,010 psi | 78% | 2828 fps | 95.2% |
| Hodgdon H4831 SC | <<locked>> | 98% | 53,272 psi | 82% | 2864 fps | 95.8% |
| Hodgdon H4895 | <<locked>> | 80% | 54,650 psi | 84% | 2835 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 33,475 psi | 51% | 2470 fps | 98.6% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 51,329 psi | 79% | 2818 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 40,640 psi | 63% | 2684 fps | 96% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,122 psi | 42% | 1585 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 52,098 psi | 80% | 2785 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 48,182 psi | 74% | 2713 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 80% | 50,314 psi | 77% | 2740 fps | 98.5% |
| IMR 4350 | <<locked>> | 82% | 39,117 psi | 60% | 2562 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 80% | 42,511 psi | 65% | 2618 fps | 96.8% |
| IMR 4831 | <<locked>> | 80% | 35,476 psi | 55% | 2520 fps | 97.6% |
| IMR 4895 | <<locked>> | 80% | 50,836 psi | 78% | 2802 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 49,559 psi | 76% | 2766 fps | 95.1% |
| IMR 7828 SSC | <<locked>> | 98% | 48,298 psi | 74% | 2844 fps | 95.2% |
| Lovex D073.6 | <<locked>> | 80% | 54,389 psi | 84% | 2802 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 52,765 psi | 81% | 2749 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 48,385 psi | 74% | 2710 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 40,016 psi | 62% | 2566 fps | 97.5% |
| Lovex S070 | <<locked>> | 80% | 38,174 psi | 59% | 2546 fps | 95.8% |
| Lovex S071 | <<locked>> | 92% | 34,374 psi | 53% | 2493 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 52,779 psi | 81% | 2769 fps | 100% |
| Norma 202 | <<locked>> | 80% | 53,490 psi | 82% | 2769 fps | 100% |
| Norma 203B | <<locked>> | 80% | 48,907 psi | 75% | 2759 fps | 100% |
| Norma 204 | <<locked>> | 86% | 44,251 psi | 68% | 2707 fps | 95.4% |
| Norma MRP | <<locked>> | 88% | 37,391 psi | 58% | 2654 fps | 95.1% |
| Norma URP | <<locked>> | 80% | 36,724 psi | 56% | 2559 fps | 97.8% |
| Ramshot Big Game | <<locked>> | 80% | 49,153 psi | 76% | 2779 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 48,472 psi | 75% | 2858 fps | 95.7% |
| Ramshot Hunter | <<locked>> | 80% | 35,665 psi | 55% | 2546 fps | 95.7% |
| Ramshot Magnum | <<locked>> | 96% | 40,074 psi | 62% | 2667 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,789 psi | 43% | 1624 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 46,862 psi | 72% | 2703 fps | 98.4% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 53,519 psi | 82% | 2890 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 43,410 psi | 67% | 2759 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 36,593 psi | 56% | 2582 fps | 97.5% |
| ReloadSwiss RS 70 | 52.6 gr | 80% | 35,694 psi | 55% | 2589 fps | 96.8% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 39,813 psi | 61% | 2743 fps | 95.9% |
| Rottweil R 902 | <<locked>> | 80% | 50,285 psi | 77% | 2723 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 43,845 psi | 67% | 2661 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 48,370 psi | 74% | 2753 fps | 95.4% |
| Rottweil R 905 | <<locked>> | 90% | 42,293 psi | 65% | 2690 fps | 95.3% |
| Rottweil R 907 | <<locked>> | 80% | 40,944 psi | 63% | 2582 fps | 95.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,016 psi | 62% | 2566 fps | 97.5% |
| Shooters World Match Rifle | <<locked>> | 80% | 54,389 psi | 84% | 2802 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 48,385 psi | 74% | 2710 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 38,174 psi | 59% | 2546 fps | 95.8% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 45,049 psi | 69% | 2713 fps | 99.9% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 52,460 psi | 81% | 2795 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 53,548 psi | 82% | 2700 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 45,295 psi | 70% | 2572 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 39,204 psi | 60% | 2513 fps | 96% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 41,887 psi | 64% | 2684 fps | 95.1% |
| Somchem S335 | <<locked>> | 80% | 53,272 psi | 82% | 2700 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 54,621 psi | 84% | 2815 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 44,251 psi | 68% | 2661 fps | 99.9% |
| Somchem S361 | <<locked>> | 94% | 53,026 psi | 82% | 2802 fps | 95.7% |
| Somchem S365 | <<locked>> | 80% | 33,243 psi | 51% | 2520 fps | 99.5% |
| Somchem S385 | <<locked>> | 88% | 40,277 psi | 62% | 2618 fps | 95.6% |
| Vihtavuori N133 | <<locked>> | 80% | 54,114 psi | 83% | 2687 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 50,546 psi | 78% | 2687 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 50,604 psi | 78% | 2700 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 42,148 psi | 65% | 2589 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 38,247 psi | 59% | 2566 fps | 98.1% |
| Vihtavuori N165 | <<locked>> | 94% | 42,264 psi | 65% | 2651 fps | 95.8% |
| Vihtavuori N540 | <<locked>> | 80% | 48,849 psi | 75% | 2694 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 37,550 psi | 58% | 2559 fps | 97.8% |
| Vihtavuori N555 | <<locked>> | 80% | 29,008 psi | 45% | 2405 fps | 95.7% |
| Vihtavuori N560 | <<locked>> | 96% | 49,530 psi | 76% | 2887 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 37,275 psi | 57% | 2533 fps | 99.5% |
| Winchester 760 | <<locked>> | 80% | 38,972 psi | 60% | 2615 fps | 95.9% |
| Winchester StaBALL HD | <<locked>> | 84% | 26,527 psi | 41% | 2415 fps | 96.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 52,301 psi | 80% | 2802 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 42,525 psi | 65% | 2661 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 104 powders for .280 Ackley Improved loaded with the .284 | 150gr | Sierra MatchKing. Alliant Reloder-26 delivers the highest muzzle velocity at 3,071 fps; across all powders the maximum-charge window runs from 1,775 fps to 3,071 fps. Accurate 3100 gives the best case fill at 100 %, and 104 of the 104 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 150.0 gr projectile in 0.284" calls for a 1:11.5 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. ReloadSwiss RS 70, Alliant Reloder-26, Alliant Reloder-16 rank at the top here: for .280 Ackley Improved with the .284 | 150gr | Sierra MatchKing 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.