Load Specifications
Load data in caliber .280 Ackley Improved with .284 | 125gr | Norma Bondstrike bullet and 98 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 60, ReloadSwiss RS 70 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.
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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% | 58,523 psi | 90% | 3022 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 57,769 psi | 89% | 3045 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 55,753 psi | 86% | 3064 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 56,478 psi | 87% | 3048 fps | 97.1% |
| Accurate 3100ᴾ | <<locked>> | 100% | 45,194 psi | 70% | 2936 fps | 96.5% |
| Accurate 4064 | <<locked>> | 90% | 57,769 psi | 89% | 3097 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 58,392 psi | 90% | 3192 fps | 99.8% |
| ADI AR 2206H | <<locked>> | 86% | 57,740 psi | 89% | 3133 fps | 100% |
| ADI AR 2208 | <<locked>> | 92% | 58,682 psi | 90% | 3130 fps | 99.9% |
| ADI Benchmark 8208 | <<locked>> | 84% | 56,391 psi | 87% | 3077 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 57,682 psi | 89% | 3048 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 58,001 psi | 89% | 3264 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 55,738 psi | 86% | 3104 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 55,970 psi | 86% | 3123 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 98% | 55,347 psi | 85% | 3192 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 94% | 56,956 psi | 88% | 3232 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 42,583 psi | 66% | 2963 fps | 99.1% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 48,225 psi | 74% | 3146 fps | 98.7% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 57,711 psi | 89% | 3146 fps | 99.8% |
| Bofors RP3 | <<locked>> | 90% | 56,492 psi | 87% | 3117 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 56,318 psi | 87% | 3087 fps | 97.3% |
| Hodgdon Benchmark | <<locked>> | 84% | 58,175 psi | 89% | 3061 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 56,217 psi | 86% | 3107 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 58,566 psi | 90% | 3219 fps | 99.9% |
| Hodgdon H380 | <<locked>> | 90% | 57,290 psi | 88% | 3133 fps | 99.4% |
| Hodgdon H414 | <<locked>> | 96% | 57,145 psi | 88% | 3182 fps | 98.1% |
| Hodgdon H4350 | <<locked>> | 94% | 57,580 psi | 89% | 3146 fps | 96.9% |
| Hodgdon H4895 | <<locked>> | 86% | 58,407 psi | 90% | 3143 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 55,376 psi | 85% | 3114 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 58,450 psi | 90% | 3179 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 57,928 psi | 89% | 3225 fps | 97.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,795 psi | 55% | 1929 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 55,898 psi | 86% | 3087 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 58,653 psi | 90% | 3123 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 58,189 psi | 90% | 3114 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 88% | 58,160 psi | 89% | 3094 fps | 98.1% |
| IMR 4350 | <<locked>> | 98% | 56,724 psi | 87% | 3114 fps | 97.4% |
| IMR 4451 Enduron | <<locked>> | 94% | 57,885 psi | 89% | 3117 fps | 98% |
| IMR 4831 | <<locked>> | 98% | 54,955 psi | 85% | 3123 fps | 99.6% |
| IMR 4895 | <<locked>> | 88% | 57,421 psi | 88% | 3156 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 56,391 psi | 87% | 3077 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 57,957 psi | 89% | 3104 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 56,753 psi | 87% | 3051 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 58,102 psi | 89% | 3107 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 57,638 psi | 89% | 3110 fps | 99% |
| Lovex S070 | <<locked>> | 96% | 55,158 psi | 85% | 3091 fps | 97.9% |
| Norma 201 | <<locked>> | 86% | 56,304 psi | 87% | 3071 fps | 100% |
| Norma 202 | <<locked>> | 86% | 56,985 psi | 88% | 3071 fps | 100% |
| Norma 203B | <<locked>> | 88% | 55,216 psi | 85% | 3107 fps | 99.9% |
| Norma 204 | <<locked>> | 98% | 57,696 psi | 89% | 3166 fps | 96.3% |
| Norma MRPᴾ | <<locked>> | 100% | 47,993 psi | 74% | 3100 fps | 96.1% |
| Norma URP | <<locked>> | 98% | 57,159 psi | 88% | 3179 fps | 99.7% |
| Ramshot Big Game | <<locked>> | 88% | 56,101 psi | 86% | 3133 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 98% | 55,883 psi | 86% | 3169 fps | 98.6% |
| Ramshot TAC | <<locked>> | 84% | 56,797 psi | 87% | 3094 fps | 99% |
| Ramshot Wild Boar | <<locked>> | 84% | 56,695 psi | 87% | 3117 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 57,246 psi | 88% | 3077 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,303 psi | 56% | 1975 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 57,377 psi | 88% | 3110 fps | 98.5% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 56,753 psi | 87% | 3192 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 56,579 psi | 87% | 3232 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 58,189 psi | 90% | 3212 fps | 99.7% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 57,479 psi | 88% | 3245 fps | 99.5% |
| Rottweil R 901 | <<locked>> | 84% | 57,072 psi | 88% | 3051 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 57,043 psi | 88% | 3071 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 56,362 psi | 87% | 3110 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 56,318 psi | 87% | 3087 fps | 97.3% |
| Shooters World Long Rifle | <<locked>> | 96% | 57,638 psi | 89% | 3110 fps | 99% |
| Shooters World Match Rifle | <<locked>> | 86% | 57,957 psi | 89% | 3104 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 58,102 psi | 89% | 3107 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 55,158 psi | 85% | 3091 fps | 97.9% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 58,247 psi | 90% | 3176 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 55,376 psi | 85% | 3071 fps | 99.2% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 56,101 psi | 86% | 3097 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 57,682 psi | 89% | 3005 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 58,175 psi | 89% | 3002 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 57,943 psi | 89% | 3061 fps | 98.1% |
| Somchem S321 | <<locked>> | 82% | 58,073 psi | 89% | 3110 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 57,058 psi | 88% | 3002 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 55,071 psi | 85% | 3061 fps | 99.9% |
| Somchem S355 | <<locked>> | 92% | 56,550 psi | 87% | 3107 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 55,376 psi | 85% | 3179 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 51,155 psi | 79% | 3045 fps | 96.3% |
| Vihtavuori N130 | <<locked>> | 82% | 57,043 psi | 88% | 2963 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 57,972 psi | 89% | 2989 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 57,000 psi | 88% | 3035 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 57,522 psi | 88% | 3048 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 57,957 psi | 89% | 3081 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 55,941 psi | 86% | 3117 fps | 99.5% |
| Vihtavuori N530 | <<locked>> | 84% | 57,072 psi | 88% | 3077 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 55,811 psi | 86% | 3045 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 58,537 psi | 90% | 3176 fps | 99.6% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 47,166 psi | 73% | 3045 fps | 99% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 56,072 psi | 86% | 3087 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 57,508 psi | 88% | 3130 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 57,464 psi | 88% | 3189 fps | 98.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 38,363 psi | 59% | 2976 fps | 99.2% |
| Winchester StaBALL Match | <<locked>> | 86% | 56,289 psi | 87% | 3110 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% | 51,619 psi | 79% | 2920 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 44,556 psi | 69% | 2841 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 52,083 psi | 80% | 3009 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 49,487 psi | 76% | 2927 fps | 95.6% |
| Accurate 3100 | <<locked>> | 98% | 41,974 psi | 65% | 2871 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 42,119 psi | 65% | 2838 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 35,781 psi | 55% | 2756 fps | 95.4% |
| ADI AR 2206H | <<locked>> | 80% | 47,790 psi | 74% | 2959 fps | 99.4% |
| ADI AR 2208 | <<locked>> | 80% | 40,524 psi | 62% | 2795 fps | 97.6% |
| ADI Benchmark 8208 | <<locked>> | 80% | 49,893 psi | 77% | 2969 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 50,560 psi | 78% | 2949 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 43,801 psi | 67% | 2995 fps | 98.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 40,567 psi | 62% | 2822 fps | 98.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 43,453 psi | 67% | 2890 fps | 98.3% |
| Alliant Reloder-16 | <<locked>> | 84% | 35,679 psi | 55% | 2772 fps | 95.5% |
| Alliant Reloder-17 | <<locked>> | 80% | 35,143 psi | 54% | 2785 fps | 97.2% |
| Alliant Reloder-23 | <<locked>> | 90% | 31,024 psi | 48% | 2661 fps | 95.2% |
| Alliant Reloder-26 | <<locked>> | 94% | 38,841 psi | 60% | 2933 fps | 96% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 47,123 psi | 72% | 2959 fps | 98.6% |
| Bofors RP3 | <<locked>> | 80% | 40,321 psi | 62% | 2825 fps | 98.9% |
| Bofors RP7 | <<locked>> | 88% | 46,528 psi | 72% | 2910 fps | 95.1% |
| Hodgdon Benchmark | <<locked>> | 80% | 51,314 psi | 79% | 2953 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 49,139 psi | 76% | 2989 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 54,389 psi | 84% | 3153 fps | 99.7% |
| Hodgdon H380 | <<locked>> | 80% | 40,944 psi | 63% | 2825 fps | 96.6% |
| Hodgdon H414 | <<locked>> | 88% | 43,671 psi | 67% | 2933 fps | 95% |
| Hodgdon H4350 | <<locked>> | 90% | 50,662 psi | 78% | 3025 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 48,312 psi | 74% | 2972 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 30,690 psi | 47% | 2598 fps | 95.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 44,498 psi | 68% | 2940 fps | 99.5% |
| Hodgdon Superformance | 61.8 gr | 90% | 46,601 psi | 72% | 3015 fps | 95.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,614 psi | 41% | 1726 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 46,151 psi | 71% | 2917 fps | 99.4% |
| IMR 3031 | <<locked>> | 80% | 48,196 psi | 74% | 2966 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 42,583 psi | 66% | 2831 fps | 98.2% |
| IMR 4166 Enduron | <<locked>> | 80% | 45,150 psi | 69% | 2858 fps | 95.4% |
| IMR 4350 | <<locked>> | 92% | 46,978 psi | 72% | 2936 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 86% | 45,252 psi | 70% | 2884 fps | 95.2% |
| IMR 4831 | <<locked>> | 84% | 34,664 psi | 53% | 2710 fps | 95.1% |
| IMR 4895 | <<locked>> | 80% | 44,541 psi | 69% | 2923 fps | 99% |
| IMR 8208 XBR | <<locked>> | 80% | 49,893 psi | 77% | 2969 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 47,398 psi | 73% | 2936 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 47,311 psi | 73% | 2887 fps | 99.3% |
| Lovex S062 | <<locked>> | 80% | 42,598 psi | 66% | 2835 fps | 99.4% |
| Lovex S065 | <<locked>> | 84% | 39,769 psi | 61% | 2772 fps | 95.3% |
| Lovex S070 | <<locked>> | 88% | 42,888 psi | 66% | 2858 fps | 95% |
| Norma 201 | <<locked>> | 80% | 46,760 psi | 72% | 2910 fps | 99.8% |
| Norma 202 | <<locked>> | 80% | 47,268 psi | 73% | 2917 fps | 100% |
| Norma 203B | <<locked>> | 80% | 42,830 psi | 66% | 2877 fps | 98.7% |
| Norma 204 | <<locked>> | 96% | 53,766 psi | 83% | 3100 fps | 95.5% |
| Norma MRP | <<locked>> | 98% | 44,773 psi | 69% | 3031 fps | 95% |
| Norma URP | <<locked>> | 84% | 36,013 psi | 55% | 2759 fps | 95.4% |
| Ramshot Big Game | <<locked>> | 80% | 42,554 psi | 65% | 2887 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 90% | 42,859 psi | 66% | 2923 fps | 95.7% |
| Ramshot TAC | <<locked>> | 80% | 49,719 psi | 76% | 2972 fps | 98% |
| Ramshot Wild Boar | <<locked>> | 80% | 49,676 psi | 76% | 2995 fps | 99.5% |
| Ramshot X-Terminator | <<locked>> | 80% | 53,679 psi | 83% | 3018 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,948 psi | 41% | 1765 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 44,034 psi | 68% | 2864 fps | 95.7% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 46,195 psi | 71% | 3005 fps | 98.8% |
| ReloadSwiss RS 60 | 52 gr | 80% | 37,362 psi | 57% | 2858 fps | 99.6% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 38,145 psi | 59% | 2835 fps | 95.9% |
| ReloadSwiss RS 70 | 56.8 gr | 86% | 38,000 psi | 58% | 2844 fps | 95% |
| Rottweil R 901 | <<locked>> | 80% | 50,807 psi | 78% | 2953 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 44,527 psi | 69% | 2858 fps | 99.6% |
| Rottweil R 903 | <<locked>> | 80% | 37,898 psi | 58% | 2762 fps | 98.1% |
| Rottweil R 907 | <<locked>> | 88% | 46,528 psi | 72% | 2910 fps | 95.1% |
| Shooters World Long Rifle | <<locked>> | 84% | 39,769 psi | 61% | 2772 fps | 95.3% |
| Shooters World Match Rifle | <<locked>> | 80% | 47,398 psi | 73% | 2936 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 42,598 psi | 66% | 2835 fps | 99.4% |
| Shooters World SW4350 | <<locked>> | 88% | 42,888 psi | 66% | 2858 fps | 95% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 38,972 psi | 60% | 2818 fps | 97.7% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 48,414 psi | 74% | 2949 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 46,282 psi | 71% | 2923 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 47,906 psi | 74% | 2858 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 40,103 psi | 62% | 2710 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 44,527 psi | 69% | 2825 fps | 95.2% |
| Somchem S321 | <<locked>> | 80% | 54,114 psi | 83% | 3051 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 47,572 psi | 73% | 2854 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 47,935 psi | 74% | 2943 fps | 99.3% |
| Somchem S355 | <<locked>> | 80% | 38,653 psi | 59% | 2769 fps | 98.1% |
| Somchem S365 | <<locked>> | 80% | 28,253 psi | 43% | 2582 fps | 95.7% |
| Somchem S385 | <<locked>> | 98% | 47,993 psi | 74% | 2986 fps | 95.5% |
| Vihtavuori N130 | <<locked>> | 80% | 53,925 psi | 83% | 2920 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 48,327 psi | 74% | 2848 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 44,280 psi | 68% | 2838 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 44,628 psi | 69% | 2841 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 36,724 psi | 56% | 2697 fps | 98.8% |
| Vihtavuori N160 | <<locked>> | 82% | 35,085 psi | 54% | 2703 fps | 95% |
| Vihtavuori N530 | <<locked>> | 80% | 50,038 psi | 77% | 2963 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 43,033 psi | 66% | 2828 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 37,072 psi | 57% | 2762 fps | 95.5% |
| Vihtavuori N555 | <<locked>> | 90% | 33,852 psi | 52% | 2749 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 32,518 psi | 50% | 2615 fps | 96.4% |
| Winchester 748 | <<locked>> | 80% | 50,183 psi | 77% | 3015 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 43,918 psi | 68% | 2940 fps | 95.1% |
| Winchester StaBALL HD | <<locked>> | 94% | 31,328 psi | 48% | 2753 fps | 96.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 46,035 psi | 71% | 2930 fps | 99.5% |
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 116 powders for .280 Ackley Improved loaded with the .284 | 125gr | Norma Bondstrike. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,264 fps; across all powders the maximum-charge window runs from 1,929 fps to 3,264 fps. Accurate 3100 gives the best case fill at 100 %, and 116 of the 116 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 1:11.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, ADI AR 2213 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, ReloadSwiss RS 70, Hodgdon Superformance rank at the top here: for .280 Ackley Improved with the .284 | 125gr | Norma Bondstrike they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, ADI AR 2213, Alliant Reloder-22, Alliant Reloder-25 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.