Load Specifications
Bullet Manufacturer:Sierra
Bullet Weight:140 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 | 140gr | Sierra GameKing 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 60, Hodgdon H414 and ReloadSwiss RS 70.
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% | 57,754 psi | 89% | 2844 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 57,711 psi | 89% | 2877 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 55,854 psi | 86% | 2890 fps | 98% |
| Accurate 3100ᴾ | <<locked>> | 100% | 48,704 psi | 75% | 2858 fps | 98.3% |
| Accurate 4064 | <<locked>> | 88% | 57,914 psi | 89% | 2930 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 58,653 psi | 90% | 3035 fps | 100% |
| ADI AR 2206H | <<locked>> | 84% | 57,188 psi | 88% | 2963 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 58,189 psi | 90% | 2963 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 55,811 psi | 86% | 3012 fps | 97.3% |
| ADI Benchmark 8208 | <<locked>> | 82% | 55,927 psi | 86% | 2907 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 57,580 psi | 89% | 2877 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 57,551 psi | 89% | 3091 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 58,740 psi | 90% | 2982 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 55,666 psi | 86% | 2956 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 96% | 55,288 psi | 85% | 3031 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 92% | 56,985 psi | 88% | 3071 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 55,042 psi | 85% | 3002 fps | 97.3% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 48,457 psi | 75% | 2933 fps | 95.9% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 45,788 psi | 70% | 2881 fps | 99.9% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 40,016 psi | 62% | 2779 fps | 96.9% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 52,112 psi | 80% | 3071 fps | 99.8% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 57,319 psi | 88% | 2979 fps | 100% |
| Bofors RP3 | <<locked>> | 88% | 56,188 psi | 86% | 2953 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 48,457 psi | 75% | 2933 fps | 95.9% |
| Bofors RP7 | <<locked>> | 92% | 55,738 psi | 86% | 2927 fps | 98.2% |
| Hodgdon Benchmark | <<locked>> | 82% | 57,130 psi | 88% | 2884 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 55,709 psi | 86% | 2936 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 56,840 psi | 87% | 2969 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 94% | 56,971 psi | 88% | 3028 fps | 98.9% |
| Hodgdon H4350 | <<locked>> | 92% | 57,043 psi | 88% | 2986 fps | 97.8% |
| Hodgdon H4895 | <<locked>> | 84% | 57,798 psi | 89% | 2972 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 55,492 psi | 85% | 2956 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 57,885 psi | 89% | 3005 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 57,522 psi | 88% | 3068 fps | 98.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,955 psi | 55% | 1818 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 58,813 psi | 90% | 2969 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 58,378 psi | 90% | 2949 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 57,914 psi | 89% | 2949 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 57,188 psi | 88% | 2930 fps | 98.8% |
| IMR 4350 | <<locked>> | 96% | 56,347 psi | 87% | 2956 fps | 98.3% |
| IMR 4451 Enduron | <<locked>> | 92% | 57,580 psi | 89% | 2959 fps | 98.8% |
| IMR 4831 | <<locked>> | 98% | 58,798 psi | 90% | 3022 fps | 100% |
| IMR 4895 | <<locked>> | 86% | 57,101 psi | 88% | 2989 fps | 100% |
| IMR 8208 XBR | <<locked>> | 82% | 55,927 psi | 86% | 2907 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 57,696 psi | 89% | 2936 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 56,101 psi | 86% | 2884 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 57,928 psi | 89% | 2943 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 57,276 psi | 88% | 2953 fps | 99.5% |
| Lovex S070 | <<locked>> | 96% | 58,508 psi | 90% | 2992 fps | 99.1% |
| Lovex S071ᴾ | <<locked>> | 100% | 40,364 psi | 62% | 2703 fps | 96.4% |
| Norma 201 | <<locked>> | 84% | 55,869 psi | 86% | 2904 fps | 100% |
| Norma 202 | <<locked>> | 84% | 56,594 psi | 87% | 2900 fps | 100% |
| Norma 203B | <<locked>> | 88% | 58,465 psi | 90% | 2995 fps | 100% |
| Norma 204 | <<locked>> | 96% | 57,145 psi | 88% | 3009 fps | 97.4% |
| Norma MRPᴾ | <<locked>> | 100% | 51,372 psi | 79% | 3018 fps | 98% |
| Norma URP | <<locked>> | 96% | 56,913 psi | 88% | 3015 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 86% | 55,666 psi | 86% | 2969 fps | 100% |
| Ramshot Hunter | <<locked>> | 96% | 55,651 psi | 86% | 3012 fps | 99.3% |
| Ramshot TAC | <<locked>> | 82% | 56,144 psi | 86% | 2930 fps | 99.5% |
| Ramshot Wild Boar | <<locked>> | 82% | 56,086 psi | 86% | 2946 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,564 psi | 56% | 1860 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 56,913 psi | 88% | 2953 fps | 99.1% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 56,695 psi | 87% | 3028 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 56,420 psi | 87% | 3061 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 58,218 psi | 90% | 3054 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 56,956 psi | 88% | 3084 fps | 99.9% |
| Rottweil R 901 | <<locked>> | 82% | 56,666 psi | 87% | 2881 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 56,637 psi | 87% | 2904 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 55,999 psi | 86% | 2943 fps | 100% |
| Rottweil R 904ᴾ | <<locked>> | 100% | 57,667 psi | 89% | 2982 fps | 96.5% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 53,983 psi | 83% | 2982 fps | 97.2% |
| Rottweil R 907 | <<locked>> | 92% | 55,738 psi | 86% | 2927 fps | 98.2% |
| Shooters World Long Rifle | <<locked>> | 94% | 57,276 psi | 88% | 2953 fps | 99.5% |
| Shooters World Match Rifle | <<locked>> | 84% | 57,696 psi | 89% | 2936 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 57,928 psi | 89% | 2943 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 58,508 psi | 90% | 2992 fps | 99.1% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 57,827 psi | 89% | 3009 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 58,740 psi | 90% | 2969 fps | 99.9% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 55,767 psi | 86% | 2933 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 57,087 psi | 88% | 2838 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 57,725 psi | 89% | 2835 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 57,421 psi | 88% | 2907 fps | 98.8% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 53,490 psi | 82% | 2976 fps | 97.1% |
| Somchem S335 | <<locked>> | 84% | 56,492 psi | 87% | 2831 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 58,407 psi | 90% | 2956 fps | 100% |
| Somchem S355 | <<locked>> | 90% | 56,043 psi | 86% | 2940 fps | 100% |
| Somchem S365 | <<locked>> | 98% | 55,651 psi | 86% | 3015 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 54,708 psi | 84% | 2959 fps | 98% |
| Vihtavuori N133 | <<locked>> | 84% | 57,508 psi | 88% | 2818 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 56,666 psi | 87% | 2864 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 57,290 psi | 88% | 2881 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 57,537 psi | 89% | 2917 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 55,564 psi | 85% | 2956 fps | 99.9% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 47,268 psi | 73% | 2818 fps | 96.1% |
| Vihtavuori N530 | <<locked>> | 82% | 56,304 psi | 87% | 2904 fps | 100% |
| Vihtavuori N540 | <<locked>> | 86% | 55,201 psi | 85% | 2874 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 58,450 psi | 90% | 3018 fps | 99.9% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 51,082 psi | 79% | 2963 fps | 99.9% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 55,695 psi | 86% | 2930 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 56,898 psi | 88% | 2956 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 57,305 psi | 88% | 3035 fps | 98.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 41,060 psi | 63% | 2913 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 84% | 55,825 psi | 86% | 2940 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 51,227 psi | 79% | 2894 fps | 96.3% |
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 2015 | <<locked>> | 80% | 54,447 psi | 84% | 2799 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 47,369 psi | 73% | 2730 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 45,818 psi | 70% | 2717 fps | 95.9% |
| Accurate 3100 | <<locked>> | 92% | 36,869 psi | 57% | 2625 fps | 95.2% |
| Accurate 4064 | <<locked>> | 80% | 44,846 psi | 69% | 2733 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 33,678 psi | 52% | 2569 fps | 96% |
| ADI AR 2206H | <<locked>> | 80% | 50,444 psi | 78% | 2854 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 80% | 42,902 psi | 66% | 2700 fps | 98.9% |
| ADI AR 2209 | <<locked>> | 96% | 48,979 psi | 75% | 2890 fps | 95.7% |
| ADI Benchmark 8208 | <<locked>> | 80% | 52,562 psi | 81% | 2854 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 53,882 psi | 83% | 2828 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 46,543 psi | 72% | 2904 fps | 99.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 43,018 psi | 66% | 2726 fps | 99.7% |
| Alliant Reloder-15 | <<locked>> | 80% | 46,050 psi | 71% | 2792 fps | 99.4% |
| Alliant Reloder-16 | <<locked>> | 80% | 33,330 psi | 51% | 2575 fps | 96% |
| Alliant Reloder-17 | <<locked>> | 80% | 37,594 psi | 58% | 2710 fps | 98.9% |
| Alliant Reloder-19 | <<locked>> | 96% | 48,443 psi | 75% | 2884 fps | 95.8% |
| Alliant Reloder-22 | <<locked>> | 98% | 45,368 psi | 70% | 2871 fps | 95.1% |
| Alliant Reloder-23 | <<locked>> | 86% | 29,370 psi | 45% | 2490 fps | 95.9% |
| Alliant Reloder-25 | <<locked>> | 98% | 37,579 psi | 58% | 2720 fps | 96% |
| Alliant Reloder-26 | <<locked>> | 88% | 33,794 psi | 52% | 2671 fps | 95.3% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 50,111 psi | 77% | 2864 fps | 99.6% |
| Bofors RP3 | <<locked>> | 80% | 43,047 psi | 66% | 2733 fps | 99.8% |
| Bofors RP5 | <<locked>> | 98% | 45,368 psi | 70% | 2871 fps | 95.1% |
| Bofors RP7 | <<locked>> | 84% | 43,511 psi | 67% | 2707 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 80% | 54,027 psi | 83% | 2838 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 52,025 psi | 80% | 2881 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 43,511 psi | 67% | 2736 fps | 98.2% |
| Hodgdon H414 | 52 gr | 84% | 40,857 psi | 63% | 2733 fps | 95.4% |
| Hodgdon H4350 | <<locked>> | 86% | 47,224 psi | 73% | 2815 fps | 95.8% |
| Hodgdon H4895 | <<locked>> | 80% | 50,995 psi | 78% | 2864 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 30,821 psi | 47% | 2474 fps | 96.8% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 47,253 psi | 73% | 2838 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 43,250 psi | 67% | 2812 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,948 psi | 41% | 1627 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 48,675 psi | 75% | 2812 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 51,416 psi | 79% | 2851 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 45,107 psi | 69% | 2736 fps | 99.4% |
| IMR 4166 Enduron | <<locked>> | 80% | 47,456 psi | 73% | 2762 fps | 97.1% |
| IMR 4350 | <<locked>> | 88% | 43,845 psi | 67% | 2736 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 82% | 42,221 psi | 65% | 2684 fps | 95.7% |
| IMR 4831 | <<locked>> | 80% | 32,605 psi | 50% | 2526 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 47,210 psi | 73% | 2822 fps | 99.8% |
| IMR 8208 XBR | <<locked>> | 80% | 52,562 psi | 81% | 2854 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 50,459 psi | 78% | 2831 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 49,821 psi | 77% | 2782 fps | 99.9% |
| Lovex S062 | <<locked>> | 80% | 45,223 psi | 70% | 2736 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 37,130 psi | 57% | 2575 fps | 95.7% |
| Lovex S070 | <<locked>> | 84% | 40,335 psi | 62% | 2667 fps | 95.5% |
| Lovex S071 | <<locked>> | 98% | 37,695 psi | 58% | 2644 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 49,255 psi | 76% | 2799 fps | 100% |
| Norma 202 | <<locked>> | 80% | 49,879 psi | 77% | 2802 fps | 100% |
| Norma 203B | <<locked>> | 80% | 45,397 psi | 70% | 2779 fps | 99.6% |
| Norma 204 | <<locked>> | 90% | 46,746 psi | 72% | 2831 fps | 95% |
| Norma MRP | <<locked>> | 94% | 41,756 psi | 64% | 2828 fps | 95.5% |
| Norma URP | <<locked>> | 80% | 33,823 psi | 52% | 2569 fps | 95.9% |
| Ramshot Big Game | <<locked>> | 80% | 45,310 psi | 70% | 2795 fps | 99.5% |
| Ramshot Hunter | <<locked>> | 84% | 37,536 psi | 58% | 2664 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 52,576 psi | 81% | 2874 fps | 99.2% |
| Ramshot Wild Boar | <<locked>> | 80% | 52,431 psi | 81% | 2890 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,369 psi | 42% | 1667 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 43,700 psi | 67% | 2720 fps | 96.9% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 49,385 psi | 76% | 2910 fps | 99.7% |
| ReloadSwiss RS 60 | 50.7 gr | 80% | 39,987 psi | 62% | 2776 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 33,330 psi | 51% | 2579 fps | 95.4% |
| ReloadSwiss RS 70 | 52.7 gr | 82% | 35,186 psi | 54% | 2641 fps | 95.4% |
| Rottweil R 901 | <<locked>> | 80% | 53,505 psi | 82% | 2835 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 47,108 psi | 72% | 2753 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 40,625 psi | 63% | 2680 fps | 99.4% |
| Rottweil R 904 | <<locked>> | 98% | 54,085 psi | 83% | 2927 fps | 95.7% |
| Rottweil R 905 | <<locked>> | 96% | 47,195 psi | 73% | 2864 fps | 95.6% |
| Rottweil R 907 | <<locked>> | 84% | 43,511 psi | 67% | 2707 fps | 95.5% |
| Shooters World Long Rifle | <<locked>> | 80% | 37,130 psi | 57% | 2575 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 50,459 psi | 78% | 2831 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 45,223 psi | 70% | 2736 fps | 100% |
| Shooters World SW4350 | <<locked>> | 84% | 40,335 psi | 62% | 2667 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 41,626 psi | 64% | 2730 fps | 99.1% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 51,169 psi | 79% | 2851 fps | 99.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 48,994 psi | 75% | 2825 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 50,415 psi | 78% | 2740 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 42,395 psi | 65% | 2605 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 41,466 psi | 64% | 2628 fps | 95.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 46,760 psi | 72% | 2858 fps | 95.5% |
| Somchem S335 | <<locked>> | 80% | 49,951 psi | 77% | 2736 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 51,024 psi | 78% | 2844 fps | 99.9% |
| Somchem S355 | <<locked>> | 80% | 40,973 psi | 63% | 2677 fps | 99.3% |
| Somchem S365 | <<locked>> | 80% | 30,298 psi | 47% | 2520 fps | 98% |
| Somchem S385 | <<locked>> | 92% | 42,018 psi | 65% | 2730 fps | 95.1% |
| Vihtavuori N133 | <<locked>> | 80% | 50,894 psi | 78% | 2726 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 47,065 psi | 72% | 2726 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 47,384 psi | 73% | 2736 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 39,218 psi | 60% | 2612 fps | 99.7% |
| Vihtavuori N160 | <<locked>> | 80% | 35,128 psi | 54% | 2569 fps | 96.3% |
| Vihtavuori N165 | <<locked>> | 98% | 44,251 psi | 68% | 2762 fps | 95.3% |
| Vihtavuori N530 | <<locked>> | 80% | 52,779 psi | 81% | 2851 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 45,542 psi | 70% | 2723 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 34,592 psi | 53% | 2566 fps | 95.9% |
| Vihtavuori N555 | <<locked>> | 84% | 29,979 psi | 46% | 2510 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 34,650 psi | 53% | 2543 fps | 98.4% |
| Winchester 748 | <<locked>> | 80% | 53,359 psi | 82% | 2904 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 41,104 psi | 63% | 2736 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 88% | 27,775 psi | 43% | 2516 fps | 95.6% |
| Winchester StaBALL Match | <<locked>> | 80% | 48,718 psi | 75% | 2828 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 47,877 psi | 74% | 2835 fps | 95.5% |
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 118 powders for .280 Ackley Improved loaded with the .284 | 140gr | Sierra GameKing. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,091 fps; across all powders the maximum-charge window runs from 1,818 fps to 3,091 fps. Accurate 3100 gives the best case fill at 100 %, and 118 of the 118 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 140.0 gr projectile in 0.284" calls for a 1:10.0 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 60, Hodgdon H414, ReloadSwiss RS 70 rank at the top here: for .280 Ackley Improved with the .284 | 140gr | Sierra GameKing 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.