Load Specifications
Bullet Manufacturer:RWS
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:1:10.0
Load data in caliber .280 Ackley Improved with .284 | 150gr | RWS Speed Tip Professional bullet and 107 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Hodgdon Superformance 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% | 55,709 psi | 86% | 2749 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 57,087 psi | 88% | 2812 fps | 98.6% |
| Accurate 3100ᴾ | <<locked>> | 100% | 50,401 psi | 78% | 2792 fps | 99% |
| Accurate 4064 | <<locked>> | 86% | 55,811 psi | 86% | 2799 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 56,275 psi | 87% | 2904 fps | 100% |
| ADI AR 2206H | <<locked>> | 84% | 58,769 psi | 90% | 2881 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 56,260 psi | 87% | 2831 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 57,682 psi | 89% | 2946 fps | 98.1% |
| ADI Benchmark 8208 | <<locked>> | 82% | 57,363 psi | 88% | 2825 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 55,390 psi | 85% | 2956 fps | 100% |
| Alliant Power Pro Varmintᴾ | <<locked>> | 100% | 57,508 psi | 88% | 2940 fps | 98.1% |
| Alliant Power Pro Varmintᴾ | <<locked>> | 100% | 57,508 psi | 88% | 2940 fps | 98.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 56,956 psi | 88% | 2858 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 57,087 psi | 88% | 2877 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 96% | 56,913 psi | 88% | 2956 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 92% | 58,595 psi | 90% | 2986 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 56,637 psi | 87% | 2930 fps | 98.1% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 50,009 psi | 77% | 2871 fps | 97% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 47,268 psi | 73% | 2812 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 41,408 psi | 64% | 2730 fps | 98.1% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 54,041 psi | 83% | 3002 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 58,711 psi | 90% | 2897 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 45,890 psi | 71% | 2792 fps | 95.8% |
| Bofors RP3 | <<locked>> | 88% | 57,885 psi | 89% | 2874 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 50,009 psi | 77% | 2871 fps | 97% |
| Bofors RP7 | <<locked>> | 92% | 57,305 psi | 88% | 2854 fps | 98.8% |
| Hodgdon Benchmark | <<locked>> | 82% | 58,436 psi | 90% | 2799 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 57,232 psi | 88% | 2854 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 58,189 psi | 90% | 2887 fps | 100% |
| Hodgdon H414 | <<locked>> | 92% | 55,100 psi | 85% | 2900 fps | 99% |
| Hodgdon H4350 | <<locked>> | 90% | 55,172 psi | 85% | 2861 fps | 98% |
| Hodgdon H4895 | <<locked>> | 82% | 55,796 psi | 86% | 2838 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 57,305 psi | 88% | 2881 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 55,912 psi | 86% | 2874 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 55,347 psi | 85% | 2936 fps | 98.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,114 psi | 56% | 1749 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 56,797 psi | 87% | 2838 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 56,449 psi | 87% | 2815 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 55,550 psi | 85% | 2812 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 58,508 psi | 90% | 2851 fps | 99.3% |
| IMR 4350 | <<locked>> | 96% | 57,899 psi | 89% | 2884 fps | 98.9% |
| IMR 4451 Enduron | <<locked>> | 90% | 55,564 psi | 85% | 2831 fps | 98.9% |
| IMR 4831 | <<locked>> | 96% | 56,913 psi | 88% | 2894 fps | 100% |
| IMR 4895 | <<locked>> | 86% | 58,595 psi | 90% | 2904 fps | 100% |
| IMR 4955 Enduronᴾ | <<locked>> | 100% | 57,145 psi | 88% | 2871 fps | 96.4% |
| IMR 8208 XBR | <<locked>> | 82% | 57,363 psi | 88% | 2825 fps | 100% |
| Lovex D073.6 | <<locked>> | 82% | 55,230 psi | 85% | 2799 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 57,406 psi | 88% | 2802 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 55,999 psi | 86% | 2812 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 58,639 psi | 90% | 2874 fps | 99.8% |
| Lovex S070 | <<locked>> | 94% | 56,391 psi | 87% | 2864 fps | 99.2% |
| Lovex S071ᴾ | <<locked>> | 100% | 41,843 psi | 64% | 2644 fps | 97.4% |
| Norma 201 | <<locked>> | 84% | 57,363 psi | 88% | 2822 fps | 100% |
| Norma 202 | <<locked>> | 84% | 57,841 psi | 89% | 2815 fps | 100% |
| Norma 203B | <<locked>> | 86% | 56,362 psi | 87% | 2861 fps | 100% |
| Norma 204 | <<locked>> | 94% | 54,998 psi | 85% | 2881 fps | 97.6% |
| Norma MRPᴾ | <<locked>> | 100% | 52,982 psi | 82% | 2953 fps | 98.8% |
| Norma URP | <<locked>> | 96% | 58,711 psi | 90% | 2940 fps | 100% |
| Ramshot Big Game | <<locked>> | 86% | 57,159 psi | 88% | 2890 fps | 100% |
| Ramshot Hunter | <<locked>> | 96% | 57,653 psi | 89% | 2943 fps | 99.7% |
| Ramshot TAC | <<locked>> | 82% | 57,580 psi | 89% | 2854 fps | 99.8% |
| Ramshot Wild Boar | <<locked>> | 82% | 57,580 psi | 89% | 2867 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,782 psi | 57% | 1791 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 58,305 psi | 90% | 2874 fps | 99.6% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 58,378 psi | 90% | 2949 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 58,262 psi | 90% | 2982 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 56,202 psi | 86% | 2927 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 58,784 psi | 90% | 3012 fps | 100% |
| Rottweil R 901 | <<locked>> | 82% | 58,233 psi | 90% | 2795 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 57,885 psi | 89% | 2822 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 57,725 psi | 89% | 2864 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 55,738 psi | 86% | 2858 fps | 96.7% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 55,622 psi | 86% | 2913 fps | 98% |
| Rottweil R 907 | <<locked>> | 92% | 57,305 psi | 88% | 2854 fps | 98.8% |
| Shooters World Long Rifle | <<locked>> | 94% | 58,639 psi | 90% | 2874 fps | 99.8% |
| Shooters World Match Rifle | <<locked>> | 82% | 55,230 psi | 85% | 2799 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 55,999 psi | 86% | 2812 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 56,391 psi | 87% | 2864 fps | 99.2% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 55,738 psi | 86% | 2874 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 56,304 psi | 87% | 2835 fps | 99.9% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 57,174 psi | 88% | 2851 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 58,392 psi | 90% | 2753 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 55,564 psi | 85% | 2707 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 55,216 psi | 85% | 2779 fps | 98.9% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 55,129 psi | 85% | 2907 fps | 97.9% |
| Somchem S335 | <<locked>> | 84% | 57,899 psi | 89% | 2749 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 56,115 psi | 86% | 2822 fps | 100% |
| Somchem S355 | <<locked>> | 90% | 57,580 psi | 89% | 2861 fps | 100% |
| Somchem S361 | <<locked>> | 98% | 57,725 psi | 89% | 2854 fps | 96.2% |
| Somchem S365 | <<locked>> | 98% | 57,812 psi | 89% | 2940 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 56,420 psi | 87% | 2890 fps | 98.7% |
| Vihtavuori N133 | <<locked>> | 84% | 58,798 psi | 90% | 2733 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 58,276 psi | 90% | 2779 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 58,682 psi | 90% | 2795 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 55,506 psi | 85% | 2785 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 57,217 psi | 88% | 2881 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 48,747 psi | 75% | 2756 fps | 97.1% |
| Vihtavuori N530 | <<locked>> | 82% | 57,812 psi | 89% | 2822 fps | 100% |
| Vihtavuori N540 | <<locked>> | 86% | 56,623 psi | 87% | 2792 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 56,289 psi | 87% | 2884 fps | 100% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 52,823 psi | 81% | 2890 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 57,334 psi | 88% | 2854 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 58,392 psi | 90% | 2871 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 55,100 psi | 85% | 2900 fps | 99% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 42,569 psi | 65% | 2858 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 84% | 57,101 psi | 88% | 2858 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 52,953 psi | 81% | 2828 fps | 97.3% |
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 2495 | <<locked>> | 80% | 48,994 psi | 75% | 2654 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 46,891 psi | 72% | 2648 fps | 96.8% |
| Accurate 3100 | <<locked>> | 90% | 35,810 psi | 55% | 2516 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 46,369 psi | 71% | 2661 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 34,882 psi | 54% | 2510 fps | 97.1% |
| ADI AR 2206H | <<locked>> | 80% | 51,735 psi | 80% | 2776 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 43,932 psi | 68% | 2628 fps | 99.4% |
| ADI AR 2209 | <<locked>> | 92% | 44,425 psi | 68% | 2717 fps | 95.1% |
| ADI Benchmark 8208 | <<locked>> | 80% | 53,838 psi | 83% | 2772 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 48,153 psi | 74% | 2835 fps | 99.9% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 44,454 psi | 68% | 2713 fps | 95.3% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 44,454 psi | 68% | 2713 fps | 95.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 44,164 psi | 68% | 2651 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 47,311 psi | 73% | 2720 fps | 99.8% |
| Alliant Reloder-16 | 45.9 gr | 80% | 34,418 psi | 53% | 2523 fps | 97.2% |
| Alliant Reloder-17 | <<locked>> | 80% | 38,696 psi | 60% | 2644 fps | 99.5% |
| Alliant Reloder-19 | <<locked>> | 92% | 43,918 psi | 68% | 2707 fps | 95.2% |
| Alliant Reloder-22 | <<locked>> | 96% | 43,787 psi | 67% | 2749 fps | 95.3% |
| Alliant Reloder-23 | <<locked>> | 82% | 26,701 psi | 41% | 2329 fps | 95.3% |
| Alliant Reloder-25 | <<locked>> | 94% | 34,171 psi | 53% | 2549 fps | 95.3% |
| Alliant Reloder-26 | <<locked>> | 86% | 32,619 psi | 50% | 2556 fps | 95.7% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 51,459 psi | 79% | 2789 fps | 99.9% |
| Bofors RP15 | <<locked>> | 98% | 43,178 psi | 66% | 2736 fps | 95% |
| Bofors RP3 | <<locked>> | 80% | 44,382 psi | 68% | 2664 fps | 100% |
| Bofors RP5 | <<locked>> | 96% | 43,787 psi | 67% | 2749 fps | 95.3% |
| Bofors RP7 | <<locked>> | 82% | 41,930 psi | 65% | 2585 fps | 95.8% |
| Hodgdon Benchmark | <<locked>> | 80% | 55,172 psi | 85% | 2753 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 53,664 psi | 83% | 2805 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 44,802 psi | 69% | 2667 fps | 98.9% |
| Hodgdon H414 | <<locked>> | 82% | 39,436 psi | 61% | 2612 fps | 95.7% |
| Hodgdon H4350 | <<locked>> | 82% | 42,656 psi | 66% | 2635 fps | 95.1% |
| Hodgdon H4895 | <<locked>> | 80% | 52,301 psi | 80% | 2785 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 31,937 psi | 49% | 2421 fps | 97.9% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 48,791 psi | 75% | 2766 fps | 100% |
| Hodgdon Superformance | 54.8 gr | 84% | 41,321 psi | 64% | 2680 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,093 psi | 42% | 1565 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 49,908 psi | 77% | 2733 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 52,736 psi | 81% | 2766 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 46,195 psi | 71% | 2661 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 80% | 48,631 psi | 75% | 2690 fps | 97.9% |
| IMR 4350 | <<locked>> | 84% | 39,856 psi | 61% | 2566 fps | 95.1% |
| IMR 4451 Enduron | <<locked>> | 80% | 40,654 psi | 63% | 2562 fps | 95.9% |
| IMR 4831 | <<locked>> | 80% | 33,692 psi | 52% | 2467 fps | 96.8% |
| IMR 4895 | <<locked>> | 80% | 48,501 psi | 75% | 2749 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 53,577 psi | 82% | 2815 fps | 95.6% |
| IMR 8208 XBR | <<locked>> | 80% | 53,838 psi | 83% | 2772 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 51,735 psi | 80% | 2749 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 50,850 psi | 78% | 2703 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 46,354 psi | 71% | 2661 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 38,334 psi | 59% | 2516 fps | 96.7% |
| Lovex S070 | <<locked>> | 82% | 38,972 psi | 60% | 2549 fps | 95.8% |
| Lovex S071 | <<locked>> | 94% | 34,389 psi | 53% | 2484 fps | 95% |
| Norma 201 | <<locked>> | 80% | 50,691 psi | 78% | 2723 fps | 100% |
| Norma 202 | <<locked>> | 80% | 51,111 psi | 79% | 2720 fps | 100% |
| Norma 203B | <<locked>> | 80% | 46,659 psi | 72% | 2707 fps | 99.9% |
| Norma 204 | <<locked>> | 88% | 44,991 psi | 69% | 2707 fps | 95.3% |
| Norma MRP | <<locked>> | 92% | 40,292 psi | 62% | 2710 fps | 95.8% |
| Norma URP | <<locked>> | 80% | 34,940 psi | 54% | 2510 fps | 97% |
| Ramshot Big Game | <<locked>> | 80% | 46,847 psi | 72% | 2730 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 82% | 36,274 psi | 56% | 2549 fps | 95.6% |
| Ramshot TAC | <<locked>> | 80% | 53,882 psi | 83% | 2799 fps | 99.6% |
| Ramshot Wild Boar | <<locked>> | 80% | 53,780 psi | 83% | 2812 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,543 psi | 42% | 1604 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 45,005 psi | 69% | 2654 fps | 97.7% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 50,734 psi | 78% | 2831 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 41,118 psi | 63% | 2703 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 34,650 psi | 53% | 2526 fps | 96.7% |
| ReloadSwiss RS 70 | 50.2 gr | 80% | 33,968 psi | 52% | 2526 fps | 95.7% |
| Rottweil R 901 | <<locked>> | 80% | 54,650 psi | 84% | 2746 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 48,225 psi | 74% | 2674 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 41,814 psi | 64% | 2608 fps | 99.8% |
| Rottweil R 904 | <<locked>> | 94% | 49,110 psi | 76% | 2749 fps | 95.2% |
| Rottweil R 905 | <<locked>> | 92% | 42,873 psi | 66% | 2690 fps | 95.1% |
| Rottweil R 907 | <<locked>> | 82% | 41,930 psi | 65% | 2585 fps | 95.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 38,334 psi | 59% | 2516 fps | 96.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 51,735 psi | 80% | 2749 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 46,354 psi | 71% | 2661 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 38,972 psi | 60% | 2549 fps | 95.8% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 42,743 psi | 66% | 2657 fps | 99.6% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 52,533 psi | 81% | 2776 fps | 99.7% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 50,111 psi | 77% | 2746 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 51,401 psi | 79% | 2654 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 43,337 psi | 67% | 2526 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 37,478 psi | 58% | 2457 fps | 95.1% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 45,194 psi | 70% | 2740 fps | 95.8% |
| Somchem S335 | <<locked>> | 80% | 51,329 psi | 79% | 2661 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 52,344 psi | 81% | 2766 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 42,308 psi | 65% | 2612 fps | 99.7% |
| Somchem S361 | <<locked>> | 96% | 53,896 psi | 83% | 2795 fps | 95.4% |
| Somchem S365 | <<locked>> | 80% | 31,314 psi | 48% | 2461 fps | 98.9% |
| Somchem S385 | <<locked>> | 90% | 40,828 psi | 63% | 2618 fps | 95.4% |
| Vihtavuori N133 | <<locked>> | 80% | 51,938 psi | 80% | 2644 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 48,196 psi | 74% | 2641 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 48,602 psi | 75% | 2657 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 40,321 psi | 62% | 2543 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 36,245 psi | 56% | 2510 fps | 97.3% |
| Vihtavuori N165 | <<locked>> | 96% | 42,627 psi | 66% | 2644 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 54,143 psi | 83% | 2772 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 46,818 psi | 72% | 2648 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 35,708 psi | 55% | 2510 fps | 97% |
| Vihtavuori N555 | <<locked>> | 82% | 29,109 psi | 45% | 2405 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 35,592 psi | 55% | 2480 fps | 99% |
| Winchester 748 | <<locked>> | 80% | 54,708 psi | 84% | 2822 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 39,624 psi | 61% | 2618 fps | 95.8% |
| Winchester StaBALL HD | <<locked>> | 86% | 26,847 psi | 41% | 2411 fps | 96.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 50,212 psi | 77% | 2756 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 46,093 psi | 71% | 2713 fps | 95.7% |
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 107 powders for .280 Ackley Improved loaded with the .284 | 150gr | RWS Speed Tip Professional. ReloadSwiss RS 70 delivers the highest muzzle velocity at 3,012 fps; across all powders the maximum-charge window runs from 1,749 fps to 3,012 fps. Accurate 3100 gives the best case fill at 100 %, and 107 of the 107 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 1:10.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, Alliant Power Pro Varmint 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, Hodgdon Superformance, Alliant Reloder-16 rank at the top here: for .280 Ackley Improved with the .284 | 150gr | RWS Speed Tip Professional 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.