Load Specifications
Load data in caliber .280 Ackley Improved with .283 | 140gr | Frontier PH HPFB bullet and 103 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-17, ReloadSwiss RS 60 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% | 57,653 psi | 89% | 2841 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 57,334 psi | 88% | 2871 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 58,653 psi | 90% | 2936 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 55,564 psi | 85% | 2881 fps | 97.9% |
| Accurate 3100ᴾ | <<locked>> | 100% | 48,153 psi | 74% | 2844 fps | 98.2% |
| Accurate 4064 | <<locked>> | 88% | 57,566 psi | 89% | 2923 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 57,986 psi | 89% | 3025 fps | 100% |
| ADI AR 2206H | <<locked>> | 84% | 56,797 psi | 87% | 2953 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 57,885 psi | 89% | 2953 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 55,521 psi | 85% | 3002 fps | 97.1% |
| ADI Benchmark 8208 | <<locked>> | 82% | 55,535 psi | 85% | 2900 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 57,188 psi | 88% | 2871 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 57,203 psi | 88% | 3084 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 58,711 psi | 90% | 2982 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 55,303 psi | 85% | 2949 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 98% | 58,668 psi | 90% | 3081 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 92% | 56,347 psi | 87% | 3058 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 54,505 psi | 84% | 2989 fps | 97.1% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 45,324 psi | 70% | 2871 fps | 99.9% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 39,784 psi | 61% | 2769 fps | 96.8% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 51,590 psi | 79% | 3058 fps | 99.7% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 57,000 psi | 88% | 2972 fps | 100% |
| Bofors RP3 | <<locked>> | 88% | 55,825 psi | 86% | 2946 fps | 100% |
| Bofors RP7 | <<locked>> | 92% | 55,434 psi | 85% | 2920 fps | 98.1% |
| Hodgdon Benchmark | <<locked>> | 82% | 57,087 psi | 88% | 2881 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 55,347 psi | 85% | 2930 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 56,550 psi | 87% | 2963 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 94% | 56,695 psi | 87% | 3022 fps | 98.8% |
| Hodgdon H4350 | <<locked>> | 92% | 56,739 psi | 87% | 2979 fps | 97.7% |
| Hodgdon H4895 | <<locked>> | 84% | 57,464 psi | 88% | 2963 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 55,187 psi | 85% | 2949 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 57,537 psi | 89% | 2999 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 57,305 psi | 88% | 3064 fps | 98.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,955 psi | 55% | 1814 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 58,769 psi | 90% | 2966 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 57,943 psi | 89% | 2940 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 57,551 psi | 89% | 2940 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 56,898 psi | 88% | 2920 fps | 98.7% |
| IMR 4350 | <<locked>> | 96% | 56,028 psi | 86% | 2949 fps | 98.2% |
| IMR 4451 Enduron | <<locked>> | 92% | 57,290 psi | 88% | 2953 fps | 98.7% |
| IMR 4831 | <<locked>> | 98% | 58,508 psi | 90% | 3015 fps | 100% |
| IMR 4895 | <<locked>> | 86% | 56,753 psi | 87% | 2979 fps | 100% |
| IMR 8208 XBR | <<locked>> | 82% | 55,535 psi | 85% | 2900 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 57,348 psi | 88% | 2930 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 56,043 psi | 86% | 2877 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 57,566 psi | 89% | 2933 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 56,971 psi | 88% | 2943 fps | 99.5% |
| Lovex S070 | <<locked>> | 96% | 58,160 psi | 89% | 2986 fps | 99% |
| Lovex S071ᴾ | <<locked>> | 100% | 40,074 psi | 62% | 2694 fps | 96.3% |
| Norma 201 | <<locked>> | 84% | 55,521 psi | 85% | 2894 fps | 100% |
| Norma 202 | <<locked>> | 84% | 56,246 psi | 87% | 2894 fps | 100% |
| Norma 203B | <<locked>> | 88% | 58,146 psi | 89% | 2989 fps | 100% |
| Norma 204 | <<locked>> | 96% | 56,913 psi | 88% | 3002 fps | 97.3% |
| Norma MRPᴾ | <<locked>> | 100% | 50,865 psi | 78% | 3009 fps | 97.9% |
| Norma URP | <<locked>> | 96% | 56,623 psi | 87% | 3009 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 86% | 55,347 psi | 85% | 2963 fps | 100% |
| Ramshot Hunter | <<locked>> | 96% | 55,405 psi | 85% | 3005 fps | 99.2% |
| Ramshot TAC | <<locked>> | 82% | 55,840 psi | 86% | 2923 fps | 99.5% |
| Ramshot Wild Boar | <<locked>> | 82% | 55,782 psi | 86% | 2940 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,564 psi | 56% | 1860 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 56,608 psi | 87% | 2943 fps | 99.1% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 56,318 psi | 87% | 3018 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 56,101 psi | 86% | 3054 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 57,885 psi | 89% | 3048 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 56,710 psi | 87% | 3077 fps | 99.9% |
| Rottweil R 901 | <<locked>> | 82% | 56,565 psi | 87% | 2874 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 56,304 psi | 87% | 2897 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 55,637 psi | 86% | 2936 fps | 100% |
| Rottweil R 904ᴾ | <<locked>> | 100% | 57,435 psi | 88% | 2976 fps | 96.3% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 53,708 psi | 83% | 2976 fps | 97.1% |
| Rottweil R 907 | <<locked>> | 92% | 55,434 psi | 85% | 2920 fps | 98.1% |
| Shooters World Long Rifle | <<locked>> | 94% | 56,971 psi | 88% | 2943 fps | 99.5% |
| Shooters World Match Rifle | <<locked>> | 84% | 57,348 psi | 88% | 2930 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 57,566 psi | 89% | 2933 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 58,160 psi | 89% | 2986 fps | 99% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 57,522 psi | 88% | 2999 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 58,407 psi | 90% | 2959 fps | 99.8% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 55,419 psi | 85% | 2927 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 56,710 psi | 87% | 2831 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 57,377 psi | 88% | 2828 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 57,188 psi | 88% | 2900 fps | 98.7% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 53,200 psi | 82% | 2969 fps | 97% |
| Somchem S335 | <<locked>> | 84% | 56,159 psi | 86% | 2825 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 58,088 psi | 89% | 2946 fps | 100% |
| Somchem S355 | <<locked>> | 90% | 55,999 psi | 86% | 2936 fps | 100% |
| Somchem S365 | <<locked>> | 98% | 55,332 psi | 85% | 3009 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 54,418 psi | 84% | 2953 fps | 97.9% |
| Vihtavuori N133 | <<locked>> | 84% | 57,116 psi | 88% | 2812 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 56,260 psi | 87% | 2854 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 56,971 psi | 88% | 2874 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 57,217 psi | 88% | 2910 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 55,274 psi | 85% | 2949 fps | 99.8% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 46,760 psi | 72% | 2805 fps | 95.9% |
| Vihtavuori N530 | <<locked>> | 82% | 56,231 psi | 87% | 2900 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 58,653 psi | 90% | 2920 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 58,160 psi | 89% | 3009 fps | 99.9% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 50,807 psi | 78% | 2953 fps | 99.9% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 55,187 psi | 85% | 2920 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 56,521 psi | 87% | 2946 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 57,029 psi | 88% | 3025 fps | 98.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 40,843 psi | 63% | 2907 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 84% | 55,521 psi | 85% | 2933 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 50,966 psi | 78% | 2884 fps | 96.2% |
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 2015 | <<locked>> | 80% | 54,070 psi | 83% | 2792 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 47,253 psi | 73% | 2726 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 54,723 psi | 84% | 2884 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 45,556 psi | 70% | 2710 fps | 95.8% |
| Accurate 3100 | <<locked>> | 92% | 36,593 psi | 56% | 2615 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 44,701 psi | 69% | 2726 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 33,359 psi | 51% | 2556 fps | 95.8% |
| ADI AR 2206H | <<locked>> | 80% | 50,082 psi | 77% | 2844 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 80% | 42,583 psi | 66% | 2690 fps | 98.8% |
| ADI AR 2209 | <<locked>> | 96% | 48,718 psi | 75% | 2884 fps | 95.6% |
| ADI Benchmark 8208 | <<locked>> | 80% | 52,185 psi | 80% | 2848 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 53,737 psi | 83% | 2822 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 46,485 psi | 72% | 2900 fps | 99.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 42,670 psi | 66% | 2717 fps | 99.7% |
| Alliant Reloder-15 | <<locked>> | 80% | 45,701 psi | 70% | 2785 fps | 99.4% |
| Alliant Reloder-16 | <<locked>> | 80% | 33,257 psi | 51% | 2572 fps | 95.9% |
| Alliant Reloder-17 | 50.4 gr | 80% | 37,289 psi | 57% | 2700 fps | 98.8% |
| Alliant Reloder-19 | <<locked>> | 96% | 47,921 psi | 74% | 2871 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 86% | 29,138 psi | 45% | 2480 fps | 95.7% |
| Alliant Reloder-25 | <<locked>> | 98% | 37,347 psi | 57% | 2710 fps | 95.8% |
| Alliant Reloder-26 | <<locked>> | 88% | 33,591 psi | 52% | 2661 fps | 95.2% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 49,806 psi | 77% | 2858 fps | 99.6% |
| Bofors RP3 | <<locked>> | 80% | 42,902 psi | 66% | 2730 fps | 99.8% |
| Bofors RP7 | <<locked>> | 84% | 43,236 psi | 67% | 2700 fps | 95.4% |
| Hodgdon Benchmark | <<locked>> | 80% | 53,664 psi | 83% | 2828 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 51,967 psi | 80% | 2877 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 43,439 psi | 67% | 2733 fps | 98.2% |
| Hodgdon H414 | <<locked>> | 84% | 40,553 psi | 62% | 2723 fps | 95.3% |
| Hodgdon H4350 | <<locked>> | 86% | 46,920 psi | 72% | 2808 fps | 95.6% |
| Hodgdon H4895 | <<locked>> | 80% | 50,647 psi | 78% | 2854 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 30,734 psi | 47% | 2470 fps | 96.7% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 47,181 psi | 73% | 2835 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 42,772 psi | 66% | 2799 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,905 psi | 41% | 1624 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 48,617 psi | 75% | 2808 fps | 99.9% |
| IMR 3031 | <<locked>> | 80% | 50,966 psi | 78% | 2841 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 44,773 psi | 69% | 2726 fps | 99.3% |
| IMR 4166 Enduron | <<locked>> | 80% | 47,166 psi | 73% | 2753 fps | 97% |
| IMR 4350 | <<locked>> | 88% | 43,584 psi | 67% | 2726 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 82% | 41,945 psi | 65% | 2674 fps | 95.5% |
| IMR 4831 | <<locked>> | 80% | 32,343 psi | 50% | 2516 fps | 95.5% |
| IMR 4895 | <<locked>> | 80% | 46,862 psi | 72% | 2815 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 80% | 52,185 psi | 80% | 2848 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 50,082 psi | 77% | 2825 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 49,458 psi | 76% | 2772 fps | 99.9% |
| Lovex S062 | <<locked>> | 80% | 44,904 psi | 69% | 2730 fps | 99.9% |
| Lovex S065 | <<locked>> | 80% | 37,057 psi | 57% | 2569 fps | 95.6% |
| Lovex S070 | <<locked>> | 84% | 40,059 psi | 62% | 2657 fps | 95.3% |
| Lovex S071 | <<locked>> | 98% | 37,434 psi | 58% | 2635 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 49,168 psi | 76% | 2795 fps | 100% |
| Norma 202 | <<locked>> | 80% | 49,487 psi | 76% | 2792 fps | 100% |
| Norma 203B | <<locked>> | 80% | 45,078 psi | 69% | 2772 fps | 99.6% |
| Norma 204 | <<locked>> | 92% | 49,617 psi | 76% | 2881 fps | 95.7% |
| Norma MRP | <<locked>> | 94% | 41,495 psi | 64% | 2818 fps | 95.3% |
| Norma URP | <<locked>> | 80% | 33,533 psi | 52% | 2559 fps | 95.7% |
| Ramshot Big Game | <<locked>> | 80% | 45,194 psi | 70% | 2792 fps | 99.5% |
| Ramshot Hunter | <<locked>> | 84% | 37,304 psi | 57% | 2657 fps | 95.1% |
| Ramshot TAC | <<locked>> | 80% | 52,315 psi | 80% | 2867 fps | 99.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 52,141 psi | 80% | 2881 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,311 psi | 42% | 1663 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 43,642 psi | 67% | 2713 fps | 96.8% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 49,023 psi | 75% | 2900 fps | 99.7% |
| ReloadSwiss RS 60 | 50.4 gr | 80% | 39,668 psi | 61% | 2766 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 33,069 psi | 51% | 2572 fps | 95.2% |
| ReloadSwiss RS 70 | 52.4 gr | 82% | 34,954 psi | 54% | 2631 fps | 95.2% |
| Rottweil R 901 | <<locked>> | 80% | 53,113 psi | 82% | 2825 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 46,775 psi | 72% | 2743 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 40,263 psi | 62% | 2671 fps | 99.3% |
| Rottweil R 904 | <<locked>> | 98% | 53,809 psi | 83% | 2917 fps | 95.6% |
| Rottweil R 905 | <<locked>> | 96% | 46,934 psi | 72% | 2854 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 84% | 43,236 psi | 67% | 2700 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 37,057 psi | 57% | 2569 fps | 95.6% |
| Shooters World Match Rifle | <<locked>> | 80% | 50,082 psi | 77% | 2825 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 44,904 psi | 69% | 2730 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 84% | 40,059 psi | 62% | 2657 fps | 95.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 41,321 psi | 64% | 2720 fps | 99% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 50,894 psi | 78% | 2841 fps | 99.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 48,704 psi | 75% | 2815 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 50,067 psi | 77% | 2733 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 42,076 psi | 65% | 2598 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 41,191 psi | 63% | 2621 fps | 95.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 96% | 46,485 psi | 72% | 2851 fps | 95.4% |
| Somchem S335 | <<locked>> | 80% | 49,850 psi | 77% | 2733 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 50,691 psi | 78% | 2835 fps | 99.9% |
| Somchem S355 | <<locked>> | 80% | 40,886 psi | 63% | 2671 fps | 99.3% |
| Somchem S365 | <<locked>> | 80% | 30,182 psi | 46% | 2513 fps | 98% |
| Somchem S385 | <<locked>> | 94% | 44,802 psi | 69% | 2785 fps | 95.9% |
| Vihtavuori N133 | <<locked>> | 80% | 50,546 psi | 78% | 2720 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 46,644 psi | 72% | 2717 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 47,021 psi | 72% | 2726 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 38,928 psi | 60% | 2605 fps | 99.7% |
| Vihtavuori N160 | <<locked>> | 80% | 34,838 psi | 54% | 2559 fps | 96.2% |
| Vihtavuori N165 | <<locked>> | 98% | 43,801 psi | 67% | 2753 fps | 95.1% |
| Vihtavuori N530 | <<locked>> | 80% | 52,721 psi | 81% | 2848 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 45,469 psi | 70% | 2720 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 34,476 psi | 53% | 2562 fps | 95.8% |
| Vihtavuori N555 | <<locked>> | 86% | 31,807 psi | 49% | 2559 fps | 95.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 34,403 psi | 53% | 2536 fps | 98.2% |
| Winchester 748 | <<locked>> | 80% | 53,026 psi | 82% | 2897 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 40,785 psi | 63% | 2726 fps | 95.3% |
| Winchester StaBALL HD | <<locked>> | 88% | 27,601 psi | 42% | 2507 fps | 95.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 48,370 psi | 74% | 2818 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 47,645 psi | 73% | 2828 fps | 95.3% |
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 .283 | 140gr | Frontier PH HPFB. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,084 fps; across all powders the maximum-charge window runs from 1,814 fps to 3,084 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 0.283" 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. Alliant Reloder-17, ReloadSwiss RS 60, ReloadSwiss RS 70 rank at the top here: for .280 Ackley Improved with the .283 | 140gr | Frontier PH HPFB 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.