Load Specifications
Load data in caliber .280 Ackley Improved with .284 | 140gr | Prvi Partizan PSP 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 70, Alliant Reloder-16 and Hodgdon Superformance.
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% | 2858 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 57,319 psi | 88% | 2920 fps | 98.3% |
| Accurate 3100ᴾ | <<locked>> | 100% | 50,357 psi | 77% | 2890 fps | 98.7% |
| Accurate 4064 | <<locked>> | 86% | 55,941 psi | 86% | 2910 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 56,463 psi | 87% | 3012 fps | 100% |
| ADI AR 2206H | <<locked>> | 84% | 58,610 psi | 90% | 2989 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 56,260 psi | 87% | 2940 fps | 100% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 57,638 psi | 89% | 3051 fps | 97.8% |
| ADI Benchmark 8208 | <<locked>> | 82% | 57,334 psi | 88% | 2933 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 84% | 55,317 psi | 85% | 3064 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 56,869 psi | 87% | 2966 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 57,043 psi | 88% | 2986 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 96% | 57,130 psi | 88% | 3068 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 92% | 58,581 psi | 90% | 3097 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 56,579 psi | 87% | 3035 fps | 97.7% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 50,183 psi | 77% | 2969 fps | 96.6% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 47,384 psi | 73% | 2917 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 41,437 psi | 64% | 2822 fps | 97.6% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 54,273 psi | 83% | 3110 fps | 99.9% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 54,882 psi | 84% | 2949 fps | 99.9% |
| Bofors RP3 | <<locked>> | 88% | 57,885 psi | 89% | 2982 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 50,183 psi | 77% | 2969 fps | 96.6% |
| Bofors RP7 | <<locked>> | 92% | 57,203 psi | 88% | 2959 fps | 98.5% |
| Hodgdon Benchmark | <<locked>> | 82% | 58,537 psi | 90% | 2910 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 57,348 psi | 88% | 2966 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 58,421 psi | 90% | 2999 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 94% | 58,755 psi | 90% | 3061 fps | 99.2% |
| Hodgdon H4350 | <<locked>> | 92% | 58,769 psi | 90% | 3022 fps | 98.2% |
| Hodgdon H4895 | <<locked>> | 82% | 55,796 psi | 86% | 2946 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 57,406 psi | 88% | 2989 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 55,738 psi | 86% | 2982 fps | 100% |
| Hodgdon Superformance | <<locked>> | 92% | 55,405 psi | 85% | 3045 fps | 98.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,172 psi | 56% | 1834 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 56,623 psi | 87% | 2946 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 56,115 psi | 86% | 2923 fps | 100% |
| IMR 4064 | <<locked>> | 86% | 55,724 psi | 86% | 2923 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 58,711 psi | 90% | 2963 fps | 99.1% |
| IMR 4350 | <<locked>> | 96% | 57,928 psi | 89% | 2989 fps | 98.7% |
| IMR 4451 Enduron | <<locked>> | 90% | 55,274 psi | 85% | 2930 fps | 98.6% |
| IMR 4831 | <<locked>> | 96% | 56,623 psi | 87% | 2995 fps | 100% |
| IMR 4895 | <<locked>> | 86% | 58,552 psi | 90% | 3015 fps | 100% |
| IMR 4955 Enduronᴾ | <<locked>> | 100% | 57,116 psi | 88% | 2972 fps | 95.9% |
| IMR 8208 XBR | <<locked>> | 82% | 57,334 psi | 88% | 2933 fps | 100% |
| Lovex D073.6 | <<locked>> | 82% | 55,361 psi | 85% | 2910 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 57,450 psi | 88% | 2910 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 55,811 psi | 86% | 2917 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 58,697 psi | 90% | 2982 fps | 99.7% |
| Lovex S070 | <<locked>> | 94% | 56,652 psi | 87% | 2972 fps | 99% |
| Lovex S071ᴾ | <<locked>> | 100% | 41,698 psi | 64% | 2733 fps | 96.9% |
| Norma 201 | <<locked>> | 84% | 57,377 psi | 88% | 2930 fps | 100% |
| Norma 202 | <<locked>> | 84% | 57,812 psi | 89% | 2923 fps | 100% |
| Norma 203B | <<locked>> | 86% | 56,333 psi | 87% | 2972 fps | 100% |
| Norma 204 | <<locked>> | 94% | 55,172 psi | 85% | 2986 fps | 97.2% |
| Norma MRPᴾ | <<locked>> | 100% | 53,200 psi | 82% | 3058 fps | 98.5% |
| Norma URP | <<locked>> | 96% | 58,784 psi | 90% | 3048 fps | 100% |
| Ramshot Big Game | <<locked>> | 86% | 57,261 psi | 88% | 2999 fps | 100% |
| Ramshot Hunter | <<locked>> | 96% | 57,667 psi | 89% | 3048 fps | 99.5% |
| Ramshot TAC | <<locked>> | 82% | 57,319 psi | 88% | 2956 fps | 99.7% |
| Ramshot Wild Boar | <<locked>> | 82% | 57,377 psi | 88% | 2972 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,782 psi | 57% | 1877 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 58,407 psi | 90% | 2982 fps | 99.4% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 58,247 psi | 90% | 3058 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 58,073 psi | 89% | 3087 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 56,289 psi | 87% | 3031 fps | 99.9% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 54,911 psi | 84% | 3058 fps | 99.8% |
| Rottweil R 901 | <<locked>> | 82% | 57,986 psi | 89% | 2907 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 57,812 psi | 89% | 2930 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 57,725 psi | 89% | 2972 fps | 100% |
| Rottweil R 904 | <<locked>> | 98% | 55,637 psi | 86% | 2959 fps | 96.2% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 55,695 psi | 86% | 3018 fps | 97.7% |
| Rottweil R 907 | <<locked>> | 92% | 57,203 psi | 88% | 2959 fps | 98.5% |
| Shooters World Long Rifle | <<locked>> | 94% | 58,697 psi | 90% | 2982 fps | 99.7% |
| Shooters World Match Rifle | <<locked>> | 82% | 55,361 psi | 85% | 2910 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 55,811 psi | 86% | 2917 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 56,652 psi | 87% | 2972 fps | 99% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 55,883 psi | 86% | 2982 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 56,405 psi | 87% | 2940 fps | 99.8% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 57,072 psi | 88% | 2959 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 58,305 psi | 90% | 2861 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 88% | 55,463 psi | 85% | 2812 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 55,259 psi | 85% | 2884 fps | 98.7% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 55,187 psi | 85% | 3012 fps | 97.6% |
| Somchem S335 | <<locked>> | 84% | 57,914 psi | 89% | 2858 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 55,840 psi | 86% | 2927 fps | 100% |
| Somchem S355 | <<locked>> | 90% | 57,653 psi | 89% | 2969 fps | 100% |
| Somchem S365 | <<locked>> | 98% | 57,624 psi | 89% | 3048 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 56,550 psi | 87% | 2995 fps | 98.5% |
| Vihtavuori N133 | <<locked>> | 84% | 58,740 psi | 90% | 2841 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 57,986 psi | 89% | 2887 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 58,697 psi | 90% | 2907 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 55,506 psi | 85% | 2894 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 57,421 psi | 88% | 2989 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 48,718 psi | 75% | 2851 fps | 96.6% |
| Vihtavuori N530 | <<locked>> | 82% | 57,740 psi | 89% | 2930 fps | 100% |
| Vihtavuori N540 | <<locked>> | 86% | 56,710 psi | 87% | 2900 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 56,565 psi | 87% | 2995 fps | 99.9% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 52,910 psi | 81% | 2995 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 57,203 psi | 88% | 2959 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 58,363 psi | 90% | 2982 fps | 100% |
| Winchester 760 | <<locked>> | 92% | 55,216 psi | 85% | 3005 fps | 98.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 42,554 psi | 65% | 2956 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 84% | 57,159 psi | 88% | 2966 fps | 100% |
| Winchester Supreme 780ᴾ | <<locked>> | 100% | 52,997 psi | 82% | 2927 fps | 96.9% |
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% | 48,718 psi | 75% | 2756 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 47,007 psi | 72% | 2746 fps | 96.4% |
| Accurate 3100 | <<locked>> | 90% | 35,752 psi | 55% | 2602 fps | 95% |
| Accurate 4064 | <<locked>> | 80% | 46,122 psi | 71% | 2756 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 34,809 psi | 54% | 2598 fps | 96.5% |
| ADI AR 2206H | <<locked>> | 80% | 51,634 psi | 79% | 2881 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 44,005 psi | 68% | 2730 fps | 99.2% |
| ADI AR 2209 | <<locked>> | 94% | 47,369 psi | 73% | 2867 fps | 95.5% |
| ADI Benchmark 8208 | <<locked>> | 80% | 53,722 psi | 83% | 2881 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 47,892 psi | 74% | 2936 fps | 99.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 44,135 psi | 68% | 2753 fps | 99.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 47,195 psi | 73% | 2822 fps | 99.6% |
| Alliant Reloder-16 | 48.3 gr | 80% | 34,272 psi | 53% | 2608 fps | 96.6% |
| Alliant Reloder-17 | <<locked>> | 80% | 38,551 psi | 59% | 2740 fps | 99.2% |
| Alliant Reloder-19 | <<locked>> | 94% | 46,746 psi | 72% | 2858 fps | 95.5% |
| Alliant Reloder-22 | <<locked>> | 98% | 46,804 psi | 72% | 2907 fps | 95.7% |
| Alliant Reloder-23 | <<locked>> | 84% | 28,456 psi | 44% | 2464 fps | 95.6% |
| Alliant Reloder-25 | <<locked>> | 96% | 36,463 psi | 56% | 2697 fps | 95.7% |
| Alliant Reloder-26 | <<locked>> | 88% | 35,099 psi | 54% | 2710 fps | 96.2% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 51,401 psi | 79% | 2894 fps | 99.8% |
| Bofors RP3 | <<locked>> | 80% | 44,411 psi | 68% | 2766 fps | 99.9% |
| Bofors RP5 | <<locked>> | 98% | 46,804 psi | 72% | 2907 fps | 95.7% |
| Bofors RP7 | <<locked>> | 82% | 41,800 psi | 64% | 2677 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 55,187 psi | 85% | 2861 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 53,403 psi | 82% | 2907 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 44,802 psi | 69% | 2769 fps | 98.6% |
| Hodgdon H414 | <<locked>> | 82% | 39,494 psi | 61% | 2707 fps | 95.1% |
| Hodgdon H4350 | <<locked>> | 84% | 45,527 psi | 70% | 2792 fps | 95.5% |
| Hodgdon H4895 | <<locked>> | 80% | 52,185 psi | 80% | 2890 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 31,792 psi | 49% | 2507 fps | 97.3% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 48,704 psi | 75% | 2867 fps | 100% |
| Hodgdon Superformance | 57.8 gr | 84% | 41,510 psi | 64% | 2779 fps | 95.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,963 psi | 41% | 1637 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 50,082 psi | 77% | 2841 fps | 100% |
| IMR 3031 | <<locked>> | 80% | 52,576 psi | 81% | 2871 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 46,253 psi | 71% | 2762 fps | 99.6% |
| IMR 4166 Enduron | <<locked>> | 80% | 48,486 psi | 75% | 2789 fps | 97.5% |
| IMR 4350 | <<locked>> | 86% | 42,279 psi | 65% | 2710 fps | 95.4% |
| IMR 4451 Enduron | <<locked>> | 80% | 40,625 psi | 63% | 2654 fps | 95.3% |
| IMR 4831 | <<locked>> | 80% | 33,634 psi | 52% | 2552 fps | 96.2% |
| IMR 4895 | <<locked>> | 80% | 48,385 psi | 74% | 2851 fps | 99.9% |
| IMR 4955 Enduron | <<locked>> | 98% | 53,461 psi | 82% | 2913 fps | 95.1% |
| IMR 8208 XBR | <<locked>> | 80% | 53,722 psi | 83% | 2881 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 51,692 psi | 80% | 2854 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 50,952 psi | 78% | 2808 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 46,412 psi | 71% | 2762 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 38,145 psi | 59% | 2605 fps | 96.2% |
| Lovex S070 | <<locked>> | 82% | 38,812 psi | 60% | 2638 fps | 95.1% |
| Lovex S071 | <<locked>> | 96% | 36,753 psi | 57% | 2625 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 50,459 psi | 78% | 2825 fps | 100% |
| Norma 202 | <<locked>> | 80% | 51,126 psi | 79% | 2828 fps | 100% |
| Norma 203B | <<locked>> | 80% | 46,586 psi | 72% | 2808 fps | 99.8% |
| Norma 204 | <<locked>> | 90% | 48,037 psi | 74% | 2861 fps | 95.6% |
| Norma MRP | <<locked>> | 92% | 40,277 psi | 62% | 2802 fps | 95.2% |
| Norma URP | <<locked>> | 80% | 34,867 psi | 54% | 2598 fps | 96.4% |
| Ramshot Big Game | <<locked>> | 80% | 46,601 psi | 72% | 2825 fps | 99.7% |
| Ramshot Hunter | <<locked>> | 84% | 38,638 psi | 59% | 2697 fps | 95.9% |
| Ramshot TAC | <<locked>> | 80% | 53,809 psi | 83% | 2900 fps | 99.4% |
| Ramshot Wild Boar | <<locked>> | 80% | 53,809 psi | 83% | 2920 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,369 psi | 42% | 1677 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 44,904 psi | 69% | 2749 fps | 97.3% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 50,676 psi | 78% | 2936 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 41,002 psi | 63% | 2799 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 34,534 psi | 53% | 2615 fps | 96% |
| ReloadSwiss RS 70 | 54.2 gr | 82% | 36,332 psi | 56% | 2680 fps | 96.1% |
| Rottweil R 901 | <<locked>> | 80% | 54,563 psi | 84% | 2854 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 48,051 psi | 74% | 2776 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 41,785 psi | 64% | 2707 fps | 99.6% |
| Rottweil R 904 | <<locked>> | 96% | 52,243 psi | 80% | 2904 fps | 95.5% |
| Rottweil R 905 | <<locked>> | 94% | 45,818 psi | 70% | 2844 fps | 95.4% |
| Rottweil R 907 | <<locked>> | 82% | 41,800 psi | 64% | 2677 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 80% | 38,145 psi | 59% | 2605 fps | 96.2% |
| Shooters World Match Rifle | <<locked>> | 80% | 51,692 psi | 80% | 2854 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 46,412 psi | 71% | 2762 fps | 100% |
| Shooters World SW4350 | <<locked>> | 82% | 38,812 psi | 60% | 2638 fps | 95.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 42,714 psi | 66% | 2756 fps | 99.3% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 52,489 psi | 81% | 2881 fps | 99.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 50,067 psi | 77% | 2848 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 51,416 psi | 79% | 2762 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 43,323 psi | 67% | 2628 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 82% | 40,016 psi | 62% | 2605 fps | 95.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 45,382 psi | 70% | 2838 fps | 95.3% |
| Somchem S335 | <<locked>> | 80% | 51,111 psi | 79% | 2762 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 52,301 psi | 80% | 2871 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 42,105 psi | 65% | 2707 fps | 99.5% |
| Somchem S365 | <<locked>> | 80% | 31,256 psi | 48% | 2546 fps | 98.5% |
| Somchem S385 | <<locked>> | 92% | 43,540 psi | 67% | 2766 fps | 95.7% |
| Vihtavuori N133 | <<locked>> | 80% | 51,938 psi | 80% | 2749 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 48,138 psi | 74% | 2746 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 48,544 psi | 75% | 2759 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 40,277 psi | 62% | 2638 fps | 99.9% |
| Vihtavuori N160 | <<locked>> | 80% | 36,187 psi | 56% | 2598 fps | 96.8% |
| Vihtavuori N165 | <<locked>> | 96% | 42,656 psi | 66% | 2736 fps | 95% |
| Vihtavuori N530 | <<locked>> | 80% | 54,259 psi | 83% | 2881 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 46,876 psi | 72% | 2749 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 35,737 psi | 55% | 2598 fps | 96.4% |
| Vihtavuori N555 | <<locked>> | 84% | 31,169 psi | 48% | 2546 fps | 95.8% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 35,563 psi | 55% | 2572 fps | 98.7% |
| Winchester 748 | <<locked>> | 80% | 54,563 psi | 84% | 2927 fps | 100% |
| Winchester 760 | <<locked>> | 82% | 39,494 psi | 61% | 2707 fps | 95.1% |
| Winchester StaBALL HD | <<locked>> | 86% | 26,832 psi | 41% | 2487 fps | 95.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 50,009 psi | 77% | 2854 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 46,137 psi | 71% | 2808 fps | 95.2% |
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 117 powders for .280 Ackley Improved loaded with the .284 | 140gr | Prvi Partizan PSP BT. Alliant Reloder-26 delivers the highest muzzle velocity at 3,110 fps; across all powders the maximum-charge window runs from 1,834 fps to 3,110 fps. Accurate 3100 gives the best case fill at 100 %, and 117 of the 117 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 140.0 gr projectile in 0.284" calls for a 1:12.0 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 70, Alliant Reloder-16, Hodgdon Superformance rank at the top here: for .280 Ackley Improved with the .284 | 140gr | Prvi Partizan PSP BT they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate MAGPRO, Hodgdon H1000, Hodgdon Retumbo 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.