Load Specifications
Load data in caliber .280 Ackley Improved with .284 | 150gr | Prvi Partizan HP BT bullet and 103 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 60, ReloadSwiss RS 70 and Alliant Reloder-26.
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>> | 84% | 57,508 psi | 88% | 2779 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 56,536 psi | 87% | 2808 fps | 98.7% |
| Accurate 3100ᴾ | <<locked>> | 100% | 52,678 psi | 81% | 2838 fps | 99.4% |
| Accurate 4064 | <<locked>> | 86% | 57,783 psi | 89% | 2831 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 58,682 psi | 90% | 2943 fps | 100% |
| ADI AR 2206H | <<locked>> | 82% | 56,739 psi | 87% | 2861 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 57,943 psi | 89% | 2867 fps | 100% |
| ADI AR 2209 | <<locked>> | 98% | 55,811 psi | 86% | 2930 fps | 98% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 53,461 psi | 82% | 2920 fps | 96.3% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 57,188 psi | 88% | 2992 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 58,755 psi | 90% | 2890 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 55,390 psi | 85% | 2861 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 55,521 psi | 85% | 2943 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 90% | 56,753 psi | 87% | 2969 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 54,955 psi | 85% | 2913 fps | 98% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 52,127 psi | 80% | 2917 fps | 97.7% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 49,153 psi | 76% | 2851 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 42,917 psi | 66% | 2772 fps | 98.6% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 56,681 psi | 87% | 3051 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 56,724 psi | 87% | 2881 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 47,877 psi | 74% | 2838 fps | 96.6% |
| Bofors RP3 | <<locked>> | 86% | 56,014 psi | 86% | 2854 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 52,127 psi | 80% | 2917 fps | 97.7% |
| Bofors RP7 | <<locked>> | 92% | 58,798 psi | 90% | 2890 fps | 99.1% |
| Hodgdon H380 | <<locked>> | 86% | 56,521 psi | 87% | 2874 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 58,450 psi | 90% | 2963 fps | 99.5% |
| Hodgdon H4350 | <<locked>> | 94% | 58,784 psi | 90% | 2930 fps | 98.7% |
| Hodgdon H4831 SCᴾ | <<locked>> | 100% | 56,115 psi | 86% | 2907 fps | 96.2% |
| Hodgdon H4895 | <<locked>> | 82% | 57,348 psi | 88% | 2871 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 55,782 psi | 86% | 2867 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 58,030 psi | 89% | 2913 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 57,580 psi | 89% | 2982 fps | 99.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,332 psi | 56% | 1765 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 57,363 psi | 88% | 2858 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 56,797 psi | 87% | 2828 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 56,753 psi | 87% | 2841 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 55,666 psi | 86% | 2822 fps | 99.1% |
| IMR 4350 | <<locked>> | 94% | 56,289 psi | 87% | 2871 fps | 98.9% |
| IMR 4451 Enduron | <<locked>> | 90% | 57,029 psi | 88% | 2867 fps | 99.2% |
| IMR 4831 | <<locked>> | 98% | 56,057 psi | 86% | 2890 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 56,797 psi | 87% | 2887 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 55,332 psi | 85% | 2854 fps | 96.3% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 54,911 psi | 84% | 2956 fps | 96.8% |
| Lovex D073.6 | <<locked>> | 82% | 57,174 psi | 88% | 2835 fps | 100% |
| Lovex S060 | <<locked>> | 82% | 55,390 psi | 85% | 2782 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 57,508 psi | 88% | 2841 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 57,145 psi | 88% | 2864 fps | 99.8% |
| Lovex S070 | <<locked>> | 94% | 58,479 psi | 90% | 2907 fps | 99.5% |
| Lovex S071ᴾ | <<locked>> | 100% | 43,511 psi | 67% | 2684 fps | 98% |
| Norma 201 | <<locked>> | 82% | 55,419 psi | 85% | 2802 fps | 100% |
| Norma 202 | <<locked>> | 82% | 56,188 psi | 86% | 2802 fps | 100% |
| Norma 203B | <<locked>> | 86% | 58,160 psi | 89% | 2897 fps | 100% |
| Norma 204 | <<locked>> | 94% | 57,276 psi | 88% | 2927 fps | 98.1% |
| Norma MRPᴾ | <<locked>> | 100% | 55,448 psi | 85% | 3002 fps | 99.2% |
| Norma URP | <<locked>> | 94% | 57,159 psi | 88% | 2927 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 55,274 psi | 85% | 2871 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 54,795 psi | 84% | 2966 fps | 97.1% |
| Ramshot Hunter | <<locked>> | 94% | 55,999 psi | 86% | 2930 fps | 99.7% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 51,285 psi | 79% | 2877 fps | 98.1% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,985 psi | 57% | 1808 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 56,231 psi | 87% | 2854 fps | 99.5% |
| ReloadSwiss RS 52 | <<locked>> | 82% | 56,347 psi | 87% | 2930 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 88% | 56,536 psi | 87% | 2966 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 58,334 psi | 90% | 2963 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 56,913 psi | 88% | 2995 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 41,916 psi | 64% | 2785 fps | 96.6% |
| Rottweil R 902 | <<locked>> | 84% | 56,173 psi | 86% | 2805 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 56,173 psi | 86% | 2851 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 57,624 psi | 89% | 2900 fps | 97.3% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 57,986 psi | 89% | 2959 fps | 98.6% |
| Rottweil R 907 | <<locked>> | 92% | 58,798 psi | 90% | 2890 fps | 99.1% |
| Shooters World Long Rifle | <<locked>> | 92% | 57,145 psi | 88% | 2864 fps | 99.8% |
| Shooters World Match Rifle | <<locked>> | 82% | 57,174 psi | 88% | 2835 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 57,508 psi | 88% | 2841 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 58,479 psi | 90% | 2907 fps | 99.5% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 57,682 psi | 89% | 2913 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 57,986 psi | 89% | 2867 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 55,071 psi | 85% | 2831 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 56,318 psi | 87% | 2736 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 57,029 psi | 88% | 2736 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 56,898 psi | 88% | 2815 fps | 99.2% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 57,479 psi | 88% | 2953 fps | 98.5% |
| Somchem S335 | <<locked>> | 82% | 55,912 psi | 86% | 2733 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 57,740 psi | 89% | 2854 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 56,043 psi | 86% | 2848 fps | 100% |
| Somchem S361 | <<locked>> | 96% | 55,709 psi | 86% | 2838 fps | 96.1% |
| Somchem S365 | <<locked>> | 96% | 56,318 psi | 87% | 2927 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 58,639 psi | 90% | 2933 fps | 99.1% |
| Unknown powder | <<locked>> | 92% | 57,841 psi | 89% | 2933 fps | 100% |
| Vihtavuori N133 | <<locked>> | 82% | 56,811 psi | 87% | 2717 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 56,289 psi | 87% | 2762 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 56,826 psi | 87% | 2782 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 57,435 psi | 88% | 2822 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 55,753 psi | 86% | 2871 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 50,821 psi | 78% | 2799 fps | 97.7% |
| Vihtavuori N540 | <<locked>> | 86% | 58,537 psi | 90% | 2825 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 58,305 psi | 90% | 2923 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 55,317 psi | 85% | 2933 fps | 100% |
| Vihtavuori N560ᴾ | <<locked>> | 100% | 55,840 psi | 86% | 2989 fps | 96.6% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 55,230 psi | 85% | 2835 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 58,450 psi | 90% | 2963 fps | 99.5% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 44,382 psi | 68% | 2907 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 57,246 psi | 88% | 2904 fps | 98.2% |
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% | 50,502 psi | 78% | 2684 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 43,540 psi | 67% | 2589 fps | 96.3% |
| Accurate 3100 | <<locked>> | 88% | 34,809 psi | 54% | 2500 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 47,819 psi | 74% | 2690 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 36,347 psi | 56% | 2549 fps | 97.7% |
| ADI AR 2206H | <<locked>> | 80% | 53,330 psi | 82% | 2812 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 45,382 psi | 70% | 2664 fps | 99.6% |
| ADI AR 2209 | <<locked>> | 90% | 43,105 psi | 66% | 2700 fps | 95% |
| ADI AR 2213 | <<locked>> | 98% | 50,053 psi | 77% | 2858 fps | 95.4% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 49,937 psi | 77% | 2874 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 45,716 psi | 70% | 2690 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 48,820 psi | 75% | 2756 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 80% | 35,534 psi | 55% | 2559 fps | 97.8% |
| Alliant Reloder-17 | <<locked>> | 80% | 40,248 psi | 62% | 2687 fps | 99.8% |
| Alliant Reloder-19 | <<locked>> | 90% | 42,685 psi | 66% | 2690 fps | 95.1% |
| Alliant Reloder-22 | <<locked>> | 94% | 42,714 psi | 66% | 2736 fps | 95.2% |
| Alliant Reloder-23 | <<locked>> | 80% | 25,991 psi | 40% | 2310 fps | 95% |
| Alliant Reloder-25 | <<locked>> | 92% | 33,417 psi | 51% | 2539 fps | 95.2% |
| Alliant Reloder-26 | 54.9 gr | 84% | 31,676 psi | 49% | 2536 fps | 95.5% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 53,098 psi | 82% | 2828 fps | 100% |
| Bofors RP15 | <<locked>> | 98% | 44,889 psi | 69% | 2779 fps | 95.8% |
| Bofors RP3 | <<locked>> | 80% | 45,934 psi | 71% | 2697 fps | 100% |
| Bofors RP5 | <<locked>> | 94% | 42,714 psi | 66% | 2736 fps | 95.2% |
| Bofors RP7 | <<locked>> | 80% | 40,582 psi | 62% | 2569 fps | 95.6% |
| Hodgdon H380 | <<locked>> | 80% | 46,238 psi | 71% | 2707 fps | 99.2% |
| Hodgdon H414 | <<locked>> | 80% | 41,626 psi | 64% | 2667 fps | 96.6% |
| Hodgdon H4350 | <<locked>> | 84% | 43,047 psi | 66% | 2654 fps | 95.5% |
| Hodgdon H4831 SC | <<locked>> | 98% | 52,547 psi | 81% | 2848 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 53,911 psi | 83% | 2818 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 33,069 psi | 51% | 2457 fps | 98.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 47,500 psi | 73% | 2753 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 39,943 psi | 61% | 2661 fps | 95.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,137 psi | 42% | 1578 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 47,776 psi | 74% | 2707 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 50,067 psi | 77% | 2733 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 44,556 psi | 69% | 2641 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,685 psi | 67% | 2608 fps | 97.1% |
| IMR 4350 | <<locked>> | 84% | 41,089 psi | 63% | 2602 fps | 95.8% |
| IMR 4451 Enduron | <<locked>> | 80% | 41,959 psi | 65% | 2598 fps | 96.5% |
| IMR 4831 | <<locked>> | 80% | 31,734 psi | 49% | 2425 fps | 96.2% |
| IMR 4895 | <<locked>> | 80% | 50,096 psi | 77% | 2785 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 51,996 psi | 80% | 2802 fps | 95.5% |
| IMR 7828 SSC | <<locked>> | 96% | 47,877 psi | 74% | 2831 fps | 95% |
| Lovex D073.6 | <<locked>> | 80% | 53,650 psi | 83% | 2785 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 52,344 psi | 81% | 2736 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 47,935 psi | 74% | 2697 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 39,421 psi | 61% | 2549 fps | 97.3% |
| Lovex S070 | <<locked>> | 80% | 37,797 psi | 58% | 2533 fps | 95.6% |
| Lovex S071 | <<locked>> | 92% | 33,663 psi | 52% | 2474 fps | 95% |
| Norma 201 | <<locked>> | 80% | 52,054 psi | 80% | 2756 fps | 100% |
| Norma 202 | <<locked>> | 80% | 52,736 psi | 81% | 2753 fps | 100% |
| Norma 203B | <<locked>> | 80% | 48,225 psi | 74% | 2743 fps | 100% |
| Norma 204 | <<locked>> | 86% | 43,511 psi | 67% | 2687 fps | 95.1% |
| Norma MRP | <<locked>> | 90% | 39,175 psi | 60% | 2690 fps | 95.6% |
| Norma URP | <<locked>> | 80% | 36,303 psi | 56% | 2546 fps | 97.6% |
| Ramshot Big Game | <<locked>> | 80% | 48,486 psi | 75% | 2766 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 47,282 psi | 73% | 2831 fps | 95.2% |
| Ramshot Hunter | <<locked>> | 80% | 35,128 psi | 54% | 2530 fps | 95.4% |
| Ramshot Magnum | <<locked>> | 94% | 40,828 psi | 63% | 2680 fps | 95.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,586 psi | 42% | 1614 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 46,282 psi | 71% | 2687 fps | 98.2% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 52,736 psi | 81% | 2874 fps | 100% |
| ReloadSwiss RS 60 | 51.1 gr | 80% | 42,786 psi | 66% | 2743 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 35,984 psi | 55% | 2566 fps | 97.3% |
| ReloadSwiss RS 70 | 51.9 gr | 80% | 35,201 psi | 54% | 2569 fps | 96.5% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 39,160 psi | 60% | 2720 fps | 95.4% |
| Rottweil R 902 | <<locked>> | 80% | 49,559 psi | 76% | 2707 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 43,366 psi | 67% | 2648 fps | 99.9% |
| Rottweil R 904 | <<locked>> | 92% | 47,630 psi | 73% | 2733 fps | 95.1% |
| Rottweil R 905 | <<locked>> | 92% | 44,585 psi | 69% | 2733 fps | 95.9% |
| Rottweil R 907 | <<locked>> | 80% | 40,582 psi | 62% | 2569 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 39,421 psi | 61% | 2549 fps | 97.3% |
| Shooters World Match Rifle | <<locked>> | 80% | 53,650 psi | 83% | 2785 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 47,935 psi | 74% | 2697 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 37,797 psi | 58% | 2533 fps | 95.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 44,411 psi | 68% | 2697 fps | 99.8% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 54,215 psi | 83% | 2812 fps | 99.9% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 51,808 psi | 80% | 2782 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 52,808 psi | 81% | 2687 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 44,599 psi | 69% | 2556 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 38,682 psi | 60% | 2493 fps | 95.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 44,164 psi | 68% | 2726 fps | 95.7% |
| Somchem S335 | <<locked>> | 80% | 52,591 psi | 81% | 2687 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 53,998 psi | 83% | 2799 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 43,584 psi | 67% | 2644 fps | 99.9% |
| Somchem S361 | <<locked>> | 94% | 52,156 psi | 80% | 2782 fps | 95.3% |
| Somchem S365 | <<locked>> | 80% | 32,634 psi | 50% | 2500 fps | 99.3% |
| Somchem S385 | <<locked>> | 88% | 39,552 psi | 61% | 2598 fps | 95.2% |
| Unknown powder | <<locked>> | 80% | 39,088 psi | 60% | 2602 fps | 97.7% |
| Vihtavuori N133 | <<locked>> | 80% | 53,345 psi | 82% | 2671 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 49,748 psi | 77% | 2671 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 50,169 psi | 77% | 2690 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 41,756 psi | 64% | 2579 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 37,637 psi | 58% | 2546 fps | 97.9% |
| Vihtavuori N165 | <<locked>> | 94% | 41,553 psi | 64% | 2631 fps | 95.4% |
| Vihtavuori N540 | <<locked>> | 80% | 48,211 psi | 74% | 2677 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 37,014 psi | 57% | 2546 fps | 97.5% |
| Vihtavuori N555 | <<locked>> | 80% | 28,442 psi | 44% | 2388 fps | 95.3% |
| Vihtavuori N560 | <<locked>> | 98% | 52,054 psi | 80% | 2927 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 36,811 psi | 57% | 2516 fps | 99.4% |
| Winchester 760 | <<locked>> | 80% | 41,626 psi | 64% | 2667 fps | 96.6% |
| Winchester StaBALL HD | <<locked>> | 84% | 26,150 psi | 40% | 2395 fps | 95.9% |
| Winchester Supreme 780 | <<locked>> | 90% | 42,786 psi | 66% | 2661 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 111 powders for .280 Ackley Improved loaded with the .284 | 150gr | Prvi Partizan HP BT. Alliant Reloder-26 delivers the highest muzzle velocity at 3,051 fps; across all powders the maximum-charge window runs from 1,765 fps to 3,051 fps. Accurate 3100 gives the best case fill at 100 %, and 111 of the 111 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (448 MPa), the top charges use 53–90 %, 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 60, ReloadSwiss RS 70, Alliant Reloder-26 rank at the top here: for .280 Ackley Improved with the .284 | 150gr | Prvi Partizan HP BT they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate MAGPRO, ADI AR 2225, Baschieri & Pellagri 109 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.