Load Specifications
Load data in caliber .280 Ackley Improved with .284 | 125gr | Lehigh Defense Controlled Chaos bullet and 98 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Power Pro 2000-MR, Alliant Reloder-17 and ReloadSwiss RS 60.
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 2015 | <<locked>> | 84% | 57,508 psi | 88% | 3005 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 56,768 psi | 87% | 3028 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 58,465 psi | 90% | 3097 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 55,564 psi | 85% | 3025 fps | 96.8% |
| Accurate 3100ᴾ | <<locked>> | 100% | 44,048 psi | 68% | 2910 fps | 96.1% |
| Accurate 4064 | <<locked>> | 90% | 56,855 psi | 87% | 3081 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 56,956 psi | 88% | 3166 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 86% | 56,652 psi | 87% | 3110 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 92% | 58,001 psi | 89% | 3114 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 84% | 55,579 psi | 86% | 3058 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 56,913 psi | 88% | 3035 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 56,971 psi | 88% | 3241 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 58,175 psi | 89% | 3136 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 90% | 58,740 psi | 90% | 3159 fps | 99.9% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 57,957 psi | 89% | 3228 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 94% | 55,680 psi | 86% | 3209 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 41,611 psi | 64% | 2936 fps | 98.9% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 46,992 psi | 72% | 3114 fps | 98.3% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 56,739 psi | 87% | 3123 fps | 99.7% |
| Bofors RP3 | <<locked>> | 90% | 55,405 psi | 85% | 3097 fps | 100% |
| Bofors RP7 | <<locked>> | 96% | 58,624 psi | 90% | 3117 fps | 97.6% |
| Hodgdon Benchmark | <<locked>> | 84% | 57,043 psi | 88% | 3038 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 55,419 psi | 85% | 3091 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 57,363 psi | 88% | 3196 fps | 99.9% |
| Hodgdon H380 | <<locked>> | 90% | 56,260 psi | 87% | 3114 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 96% | 56,188 psi | 86% | 3166 fps | 97.8% |
| Hodgdon H4350 | <<locked>> | 94% | 56,347 psi | 87% | 3120 fps | 96.5% |
| Hodgdon H4895 | <<locked>> | 86% | 57,217 psi | 88% | 3120 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 54,317 psi | 84% | 3094 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 57,029 psi | 88% | 3156 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 56,927 psi | 88% | 3202 fps | 97.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,636 psi | 55% | 1919 fps | 100% |
| Hodgdon VARGET | <<locked>> | 88% | 58,682 psi | 90% | 3127 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 57,595 psi | 89% | 3107 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 57,421 psi | 88% | 3094 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 88% | 57,159 psi | 88% | 3071 fps | 97.8% |
| IMR 4350 | <<locked>> | 98% | 55,608 psi | 86% | 3087 fps | 97.1% |
| IMR 4451 Enduron | <<locked>> | 94% | 56,985 psi | 88% | 3097 fps | 97.7% |
| IMR 4831ᴾ | <<locked>> | 100% | 57,566 psi | 89% | 3159 fps | 99.7% |
| IMR 4895 | <<locked>> | 88% | 56,637 psi | 87% | 3136 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 55,579 psi | 86% | 3058 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 56,768 psi | 87% | 3084 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 55,985 psi | 86% | 3031 fps | 99.9% |
| Lovex S062 | <<locked>> | 90% | 57,261 psi | 88% | 3091 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 56,724 psi | 87% | 3091 fps | 98.8% |
| Lovex S070 | <<locked>> | 98% | 57,711 psi | 89% | 3127 fps | 98.2% |
| Norma 201 | <<locked>> | 86% | 55,477 psi | 85% | 3051 fps | 100% |
| Norma 202 | <<locked>> | 86% | 56,101 psi | 86% | 3054 fps | 100% |
| Norma 203B | <<locked>> | 90% | 57,928 psi | 89% | 3146 fps | 100% |
| Norma 204 | <<locked>> | 98% | 56,478 psi | 87% | 3140 fps | 95.9% |
| Norma URP | <<locked>> | 98% | 55,840 psi | 86% | 3153 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 90% | 58,668 psi | 90% | 3169 fps | 100% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 58,349 psi | 90% | 3202 fps | 98.8% |
| Ramshot TAC | <<locked>> | 84% | 55,912 psi | 86% | 3074 fps | 98.8% |
| Ramshot Wild Boar | <<locked>> | 84% | 55,637 psi | 86% | 3094 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 82% | 56,492 psi | 87% | 3058 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,143 psi | 56% | 1965 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 82% | 58,595 psi | 90% | 3091 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 56,405 psi | 87% | 3087 fps | 98.2% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 55,492 psi | 85% | 3169 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 55,274 psi | 85% | 3209 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 56,869 psi | 87% | 3189 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 56,057 psi | 86% | 3219 fps | 99.3% |
| Rottweil R 901 | <<locked>> | 84% | 56,434 psi | 87% | 3038 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 55,898 psi | 86% | 3051 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 55,245 psi | 85% | 3091 fps | 100% |
| Rottweil R 907 | <<locked>> | 96% | 58,624 psi | 90% | 3117 fps | 97.6% |
| Shooters World Long Rifle | <<locked>> | 96% | 56,724 psi | 87% | 3091 fps | 98.8% |
| Shooters World Match Rifle | <<locked>> | 86% | 56,768 psi | 87% | 3084 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 57,261 psi | 88% | 3091 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 57,711 psi | 89% | 3127 fps | 98.2% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 56,913 psi | 88% | 3153 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 58,508 psi | 90% | 3114 fps | 99.4% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 55,100 psi | 85% | 3077 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 56,782 psi | 87% | 2989 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 57,363 psi | 88% | 2989 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 57,029 psi | 88% | 3041 fps | 97.8% |
| Somchem S321 | <<locked>> | 82% | 57,014 psi | 88% | 3091 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 56,217 psi | 86% | 2986 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 57,841 psi | 89% | 3100 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 55,463 psi | 85% | 3084 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 53,969 psi | 83% | 3156 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 50,053 psi | 77% | 3022 fps | 95.9% |
| Vihtavuori N130 | <<locked>> | 82% | 56,376 psi | 87% | 2949 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 57,043 psi | 88% | 2972 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 55,695 psi | 86% | 3012 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 56,739 psi | 87% | 3031 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 56,971 psi | 88% | 3064 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 58,320 psi | 90% | 3150 fps | 99.6% |
| Vihtavuori N530 | <<locked>> | 84% | 56,188 psi | 86% | 3058 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 58,581 psi | 90% | 3081 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 57,334 psi | 88% | 3150 fps | 99.5% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 46,180 psi | 71% | 3025 fps | 98.8% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 55,013 psi | 85% | 3071 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 56,304 psi | 87% | 3107 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 56,188 psi | 86% | 3166 fps | 97.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 37,347 psi | 57% | 2940 fps | 98.8% |
| Winchester StaBALL Match | <<locked>> | 86% | 55,230 psi | 85% | 3087 fps | 100% |
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% | 50,894 psi | 78% | 2907 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 43,598 psi | 67% | 2822 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 50,908 psi | 78% | 2986 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 48,530 psi | 75% | 2904 fps | 95.2% |
| Accurate 3100 | <<locked>> | 98% | 40,886 psi | 63% | 2844 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 41,205 psi | 63% | 2815 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 34,983 psi | 54% | 2733 fps | 95% |
| ADI AR 2206H | <<locked>> | 80% | 46,963 psi | 72% | 2940 fps | 99.2% |
| ADI AR 2208 | <<locked>> | 80% | 39,972 psi | 61% | 2776 fps | 97.3% |
| ADI Benchmark 8208 | <<locked>> | 80% | 49,037 psi | 75% | 2949 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 49,719 psi | 76% | 2933 fps | 100% |
| Alliant Power Pro 2000-MR | 51.9 gr | 80% | 43,047 psi | 66% | 2972 fps | 98% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 39,726 psi | 61% | 2799 fps | 98.6% |
| Alliant Reloder-15 | <<locked>> | 80% | 42,641 psi | 66% | 2867 fps | 98.1% |
| Alliant Reloder-16 | <<locked>> | 84% | 35,012 psi | 54% | 2749 fps | 95.1% |
| Alliant Reloder-17 | 51.1 gr | 80% | 34,461 psi | 53% | 2762 fps | 96.8% |
| Alliant Reloder-23 | <<locked>> | 92% | 32,445 psi | 50% | 2700 fps | 95.8% |
| Alliant Reloder-26 | <<locked>> | 94% | 37,942 psi | 58% | 2904 fps | 95.5% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 46,354 psi | 71% | 2940 fps | 98.4% |
| Bofors RP3 | <<locked>> | 80% | 39,523 psi | 61% | 2805 fps | 98.7% |
| Bofors RP7 | <<locked>> | 90% | 48,805 psi | 75% | 2949 fps | 95.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 50,473 psi | 78% | 2933 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 48,341 psi | 74% | 2972 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 53,505 psi | 82% | 3133 fps | 99.6% |
| Hodgdon H380 | <<locked>> | 80% | 40,161 psi | 62% | 2805 fps | 96.2% |
| Hodgdon H414 | <<locked>> | 90% | 45,847 psi | 71% | 2976 fps | 95.5% |
| Hodgdon H4350 | <<locked>> | 90% | 49,719 psi | 76% | 3002 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 47,442 psi | 73% | 2953 fps | 99.5% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 30,211 psi | 46% | 2582 fps | 95% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 43,685 psi | 67% | 2920 fps | 99.4% |
| Hodgdon Superformance | <<locked>> | 92% | 49,197 psi | 76% | 3064 fps | 95.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,542 psi | 41% | 1716 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 45,353 psi | 70% | 2897 fps | 99.3% |
| IMR 3031 | <<locked>> | 80% | 47,166 psi | 73% | 2943 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 41,959 psi | 65% | 2815 fps | 98% |
| IMR 4166 Enduron | <<locked>> | 80% | 44,411 psi | 68% | 2835 fps | 95% |
| IMR 4350 | <<locked>> | 94% | 49,081 psi | 76% | 2972 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 88% | 47,384 psi | 73% | 2923 fps | 95.7% |
| IMR 4831 | <<locked>> | 86% | 36,245 psi | 56% | 2749 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 43,685 psi | 67% | 2900 fps | 98.8% |
| IMR 8208 XBR | <<locked>> | 80% | 49,037 psi | 75% | 2949 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 46,514 psi | 72% | 2920 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 46,775 psi | 72% | 2871 fps | 99.2% |
| Lovex S062 | <<locked>> | 80% | 42,003 psi | 65% | 2822 fps | 99.3% |
| Lovex S065 | <<locked>> | 86% | 41,553 psi | 64% | 2808 fps | 95.7% |
| Lovex S070 | <<locked>> | 90% | 44,933 psi | 69% | 2897 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 45,890 psi | 71% | 2887 fps | 99.7% |
| Norma 202 | <<locked>> | 80% | 46,383 psi | 71% | 2897 fps | 100% |
| Norma 203B | <<locked>> | 80% | 42,003 psi | 65% | 2858 fps | 98.4% |
| Norma 204 | <<locked>> | 96% | 52,634 psi | 81% | 3074 fps | 95% |
| Norma URP | <<locked>> | 84% | 35,302 psi | 54% | 2736 fps | 95% |
| Ramshot Big Game | <<locked>> | 80% | 41,800 psi | 64% | 2871 fps | 98.2% |
| Ramshot Hunter | <<locked>> | 90% | 41,974 psi | 65% | 2900 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 49,037 psi | 75% | 2953 fps | 97.8% |
| Ramshot Wild Boar | <<locked>> | 80% | 48,660 psi | 75% | 2976 fps | 99.4% |
| Ramshot X-Terminator | <<locked>> | 80% | 52,939 psi | 81% | 3002 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,861 psi | 41% | 1755 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 54,766 psi | 84% | 3031 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 43,381 psi | 67% | 2848 fps | 95.4% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 45,266 psi | 70% | 2982 fps | 98.5% |
| ReloadSwiss RS 60 | 51.1 gr | 80% | 36,680 psi | 56% | 2835 fps | 99.5% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 37,202 psi | 57% | 2808 fps | 95.5% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 39,856 psi | 61% | 2887 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 50,082 psi | 77% | 2936 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 43,671 psi | 67% | 2835 fps | 99.5% |
| Rottweil R 903 | <<locked>> | 80% | 37,260 psi | 57% | 2746 fps | 97.9% |
| Rottweil R 907 | <<locked>> | 90% | 48,805 psi | 75% | 2949 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 86% | 41,553 psi | 64% | 2808 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 46,514 psi | 72% | 2920 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 42,003 psi | 65% | 2822 fps | 99.3% |
| Shooters World SW4350 | <<locked>> | 90% | 44,933 psi | 69% | 2897 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 38,218 psi | 59% | 2795 fps | 97.4% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 47,413 psi | 73% | 2927 fps | 97.9% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 45,498 psi | 70% | 2904 fps | 99% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 47,007 psi | 72% | 2835 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 39,305 psi | 60% | 2690 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 46,818 psi | 72% | 2864 fps | 95.7% |
| Somchem S321 | <<locked>> | 80% | 53,301 psi | 82% | 3035 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 46,760 psi | 72% | 2838 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 47,195 psi | 73% | 2923 fps | 99.2% |
| Somchem S355 | <<locked>> | 80% | 37,855 psi | 58% | 2749 fps | 97.9% |
| Somchem S365 | <<locked>> | 80% | 27,615 psi | 42% | 2556 fps | 95.2% |
| Somchem S385 | <<locked>> | 98% | 46,920 psi | 72% | 2963 fps | 95% |
| Vihtavuori N130 | <<locked>> | 80% | 52,953 psi | 81% | 2900 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 47,398 psi | 73% | 2828 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 43,294 psi | 67% | 2815 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 44,019 psi | 68% | 2828 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 36,187 psi | 56% | 2684 fps | 98.6% |
| Vihtavuori N160 | <<locked>> | 84% | 36,724 psi | 56% | 2740 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 49,153 psi | 76% | 2943 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 80% | 42,264 psi | 65% | 2812 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 36,201 psi | 56% | 2740 fps | 95% |
| Vihtavuori N555 | <<locked>> | 90% | 32,982 psi | 51% | 2726 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,995 psi | 49% | 2595 fps | 96% |
| Winchester 748 | <<locked>> | 80% | 49,269 psi | 76% | 2995 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 46,064 psi | 71% | 2979 fps | 95.6% |
| Winchester StaBALL HD | <<locked>> | 94% | 30,748 psi | 47% | 2723 fps | 95.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 45,005 psi | 69% | 2907 fps | 99.3% |
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 98 powders for .280 Ackley Improved loaded with the .284 | 125gr | Lehigh Defense Controlled Chaos. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,241 fps; across all powders the maximum-charge window runs from 1,919 fps to 3,241 fps. Accurate 3100 gives the best case fill at 100 %, and 98 of the 98 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 125.0 gr projectile in 0.284" calls for a 1:10.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Reloder-16, Alliant Reloder-23 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 Power Pro 2000-MR, Alliant Reloder-17, ReloadSwiss RS 60 rank at the top here: for .280 Ackley Improved with the .284 | 125gr | Lehigh Defense Controlled Chaos 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.