Load Specifications
Load data in caliber .280 Ackley Improved with .284 | 135gr | CutEdge ER Raptor bullet and 99 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% | 56,811 psi | 87% | 2877 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 55,709 psi | 86% | 2904 fps | 100% |
| Accurate 2520 | <<locked>> | 84% | 57,783 psi | 89% | 2976 fps | 100% |
| Accurate 2700 | <<locked>> | 90% | 58,740 psi | 90% | 2966 fps | 97.8% |
| Accurate 3100ᴾ | <<locked>> | 100% | 42,902 psi | 66% | 2792 fps | 96.4% |
| Accurate 4064 | <<locked>> | 90% | 55,767 psi | 86% | 2953 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 56,333 psi | 87% | 3048 fps | 99.8% |
| ADI AR 2206H | <<locked>> | 86% | 56,202 psi | 86% | 2989 fps | 100% |
| ADI AR 2208 | <<locked>> | 92% | 57,348 psi | 88% | 2989 fps | 99.9% |
| ADI Benchmark 8208 | <<locked>> | 86% | 58,755 psi | 90% | 2989 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 56,130 psi | 86% | 2907 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 56,362 psi | 87% | 3117 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 92% | 57,479 psi | 88% | 3012 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 90% | 57,986 psi | 89% | 3035 fps | 100% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 57,334 psi | 88% | 3107 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 94% | 55,071 psi | 85% | 3084 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 41,031 psi | 63% | 2828 fps | 99.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 46,267 psi | 71% | 3002 fps | 98.7% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 56,275 psi | 87% | 3005 fps | 99.8% |
| Bofors RP3 | <<locked>> | 92% | 58,450 psi | 90% | 3028 fps | 100% |
| Bofors RP7 | <<locked>> | 96% | 58,247 psi | 90% | 3002 fps | 98% |
| Hodgdon Benchmark | <<locked>> | 84% | 56,768 psi | 87% | 2920 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 86% | 58,639 psi | 90% | 3025 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 57,000 psi | 88% | 3074 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 55,593 psi | 86% | 2992 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 96% | 55,579 psi | 86% | 3045 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 94% | 55,825 psi | 86% | 3002 fps | 97% |
| Hodgdon H4895 | <<locked>> | 86% | 56,840 psi | 87% | 2999 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 53,548 psi | 82% | 2972 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 56,550 psi | 87% | 3035 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 56,275 psi | 87% | 3084 fps | 98% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,549 psi | 55% | 1831 fps | 100% |
| Hodgdon VARGET | <<locked>> | 88% | 58,189 psi | 90% | 3002 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 56,956 psi | 88% | 2979 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 56,884 psi | 88% | 2972 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 56,782 psi | 87% | 2956 fps | 98.2% |
| IMR 4350ᴾ | <<locked>> | 100% | 58,726 psi | 90% | 3028 fps | 98.1% |
| IMR 4451 Enduron | <<locked>> | 94% | 56,608 psi | 87% | 2979 fps | 98.1% |
| IMR 4831ᴾ | <<locked>> | 100% | 56,898 psi | 88% | 3038 fps | 99.8% |
| IMR 4895 | <<locked>> | 88% | 56,014 psi | 86% | 3015 fps | 100% |
| IMR 8208 XBR | <<locked>> | 86% | 58,755 psi | 90% | 2989 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 56,028 psi | 86% | 2963 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 55,477 psi | 85% | 2913 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 56,565 psi | 87% | 2966 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 55,912 psi | 86% | 2969 fps | 99.1% |
| Lovex S070 | <<locked>> | 98% | 57,130 psi | 88% | 3012 fps | 98.5% |
| Norma 201 | <<locked>> | 88% | 58,479 psi | 90% | 2986 fps | 100% |
| Norma 202 | <<locked>> | 86% | 55,521 psi | 85% | 2933 fps | 100% |
| Norma 203B | <<locked>> | 90% | 57,159 psi | 88% | 3018 fps | 100% |
| Norma 204 | <<locked>> | 98% | 55,854 psi | 86% | 3025 fps | 96.4% |
| Norma MRPᴾ | <<locked>> | 100% | 46,122 psi | 71% | 2956 fps | 96% |
| Norma URP | <<locked>> | 98% | 55,376 psi | 85% | 3035 fps | 99.7% |
| Ramshot Big Game | <<locked>> | 90% | 58,189 psi | 90% | 3048 fps | 100% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 57,783 psi | 89% | 3084 fps | 99.1% |
| Ramshot TAC | <<locked>> | 84% | 55,550 psi | 85% | 2959 fps | 99.1% |
| Ramshot Wild Boar | <<locked>> | 84% | 55,216 psi | 85% | 2976 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 55,956 psi | 86% | 2940 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,071 psi | 55% | 1873 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 82% | 58,059 psi | 89% | 2966 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 55,680 psi | 86% | 2969 fps | 98.6% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 54,998 psi | 85% | 3048 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 94% | 58,711 psi | 90% | 3140 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 56,144 psi | 86% | 3068 fps | 99.7% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 55,593 psi | 86% | 3100 fps | 99.6% |
| Rottweil R 901 | <<locked>> | 84% | 55,492 psi | 85% | 2910 fps | 100% |
| Rottweil R 902 | <<locked>> | 90% | 58,682 psi | 90% | 2976 fps | 100% |
| Rottweil R 903 | <<locked>> | 94% | 58,305 psi | 90% | 3022 fps | 100% |
| Rottweil R 907 | <<locked>> | 96% | 58,247 psi | 90% | 3002 fps | 98% |
| Shooters World Long Rifle | <<locked>> | 96% | 55,912 psi | 86% | 2969 fps | 99.1% |
| Shooters World Match Rifle | <<locked>> | 86% | 56,028 psi | 86% | 2963 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 56,565 psi | 87% | 2966 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 57,130 psi | 88% | 3012 fps | 98.5% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 56,347 psi | 87% | 3028 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 57,580 psi | 89% | 2989 fps | 99.6% |
| SNPE Vectan SP 9 | <<locked>> | 88% | 58,276 psi | 90% | 3012 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 56,318 psi | 87% | 2871 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 56,826 psi | 87% | 2867 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 56,115 psi | 86% | 2920 fps | 98.1% |
| Somchem S321 | <<locked>> | 82% | 56,405 psi | 87% | 2969 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 55,608 psi | 86% | 2864 fps | 100% |
| Somchem S341 | <<locked>> | 86% | 57,392 psi | 88% | 2982 fps | 100% |
| Somchem S355 | <<locked>> | 94% | 58,407 psi | 90% | 3018 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 53,301 psi | 82% | 3031 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 49,429 psi | 76% | 2910 fps | 96.4% |
| Vihtavuori N130 | <<locked>> | 82% | 55,941 psi | 86% | 2828 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 56,695 psi | 87% | 2851 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 55,303 psi | 85% | 2894 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 56,101 psi | 86% | 2910 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 56,434 psi | 87% | 2943 fps | 100% |
| Vihtavuori N160 | <<locked>> | 98% | 57,943 psi | 89% | 3031 fps | 99.8% |
| Vihtavuori N530 | <<locked>> | 84% | 55,724 psi | 86% | 2940 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 57,986 psi | 89% | 2956 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 56,739 psi | 87% | 3035 fps | 99.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 45,295 psi | 70% | 2907 fps | 99.1% |
| Winchester 6.5 StaBALL | <<locked>> | 98% | 58,291 psi | 90% | 3009 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 55,796 psi | 86% | 2986 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 55,579 psi | 86% | 3045 fps | 98.2% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 36,550 psi | 56% | 2831 fps | 99.2% |
| Winchester StaBALL Match | <<locked>> | 88% | 58,378 psi | 90% | 3022 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% | 50,154 psi | 77% | 2785 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 42,496 psi | 65% | 2700 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 50,140 psi | 77% | 2864 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 48,182 psi | 74% | 2795 fps | 95.7% |
| Accurate 3100 | <<locked>> | 98% | 40,089 psi | 62% | 2733 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 40,219 psi | 62% | 2697 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 34,098 psi | 52% | 2621 fps | 95.4% |
| ADI AR 2206H | <<locked>> | 80% | 46,325 psi | 71% | 2822 fps | 99.4% |
| ADI AR 2208 | <<locked>> | 80% | 39,291 psi | 60% | 2661 fps | 97.7% |
| ADI Benchmark 8208 | <<locked>> | 80% | 48,486 psi | 75% | 2831 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 49,211 psi | 76% | 2812 fps | 100% |
| Alliant Power Pro 2000-MR | 49.5 gr | 80% | 42,322 psi | 65% | 2854 fps | 98.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 39,204 psi | 60% | 2690 fps | 98.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 41,959 psi | 65% | 2753 fps | 98.4% |
| Alliant Reloder-16 | <<locked>> | 84% | 34,490 psi | 53% | 2644 fps | 95.7% |
| Alliant Reloder-17 | 48.8 gr | 80% | 33,794 psi | 52% | 2654 fps | 97.2% |
| Alliant Reloder-23 | <<locked>> | 90% | 29,762 psi | 46% | 2536 fps | 95.2% |
| Alliant Reloder-26 | <<locked>> | 94% | 36,985 psi | 57% | 2789 fps | 95.9% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 45,977 psi | 71% | 2831 fps | 98.7% |
| Bofors RP3 | <<locked>> | 80% | 38,696 psi | 60% | 2690 fps | 98.9% |
| Bofors RP7 | <<locked>> | 88% | 45,063 psi | 69% | 2776 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 50,140 psi | 77% | 2818 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 47,485 psi | 73% | 2848 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 52,939 psi | 81% | 3009 fps | 99.8% |
| Hodgdon H380 | <<locked>> | 80% | 39,523 psi | 61% | 2694 fps | 96.7% |
| Hodgdon H414 | <<locked>> | 88% | 42,279 psi | 65% | 2802 fps | 95.1% |
| Hodgdon H4350 | <<locked>> | 90% | 49,153 psi | 76% | 2887 fps | 95.5% |
| Hodgdon H4895 | <<locked>> | 80% | 46,789 psi | 72% | 2835 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 29,501 psi | 45% | 2474 fps | 95.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 43,062 psi | 66% | 2805 fps | 99.6% |
| Hodgdon Superformance | <<locked>> | 90% | 45,063 psi | 69% | 2881 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,455 psi | 41% | 1637 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 45,063 psi | 69% | 2785 fps | 99.5% |
| IMR 3031 | <<locked>> | 80% | 46,615 psi | 72% | 2825 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 41,249 psi | 63% | 2700 fps | 98.3% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,932 psi | 68% | 2726 fps | 95.5% |
| IMR 4350 | <<locked>> | 92% | 45,585 psi | 70% | 2805 fps | 95.4% |
| IMR 4451 Enduron | <<locked>> | 86% | 44,077 psi | 68% | 2756 fps | 95.4% |
| IMR 4831 | <<locked>> | 84% | 33,127 psi | 51% | 2579 fps | 95.1% |
| IMR 4895 | <<locked>> | 80% | 43,004 psi | 66% | 2785 fps | 99% |
| IMR 8208 XBR | <<locked>> | 80% | 48,486 psi | 75% | 2831 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 45,600 psi | 70% | 2795 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 46,093 psi | 71% | 2753 fps | 99.4% |
| Lovex S062 | <<locked>> | 80% | 41,104 psi | 63% | 2700 fps | 99.5% |
| Lovex S065 | <<locked>> | 84% | 38,421 psi | 59% | 2641 fps | 95.4% |
| Lovex S070 | <<locked>> | 88% | 41,379 psi | 64% | 2726 fps | 95% |
| Norma 201 | <<locked>> | 80% | 45,208 psi | 70% | 2769 fps | 99.8% |
| Norma 202 | <<locked>> | 80% | 45,861 psi | 71% | 2779 fps | 100% |
| Norma 203B | <<locked>> | 80% | 41,321 psi | 64% | 2743 fps | 98.7% |
| Norma 204 | <<locked>> | 96% | 52,069 psi | 80% | 2959 fps | 95.6% |
| Norma MRP | <<locked>> | 98% | 43,062 psi | 66% | 2890 fps | 95.1% |
| Norma URP | <<locked>> | 84% | 34,563 psi | 53% | 2628 fps | 95.4% |
| Ramshot Big Game | <<locked>> | 80% | 41,046 psi | 63% | 2753 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 90% | 41,234 psi | 63% | 2789 fps | 95.8% |
| Ramshot TAC | <<locked>> | 80% | 48,602 psi | 75% | 2841 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 48,167 psi | 74% | 2861 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 80% | 52,257 psi | 80% | 2881 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,774 psi | 41% | 1677 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 54,346 psi | 84% | 2913 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 40,045 psi | 62% | 2680 fps | 95.1% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 44,556 psi | 69% | 2864 fps | 98.8% |
| ReloadSwiss RS 60 | 48.8 gr | 80% | 36,056 psi | 55% | 2723 fps | 99.7% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 34,113 psi | 52% | 2641 fps | 95% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 36,622 psi | 56% | 2710 fps | 95.1% |
| Rottweil R 901 | <<locked>> | 80% | 49,124 psi | 76% | 2812 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,902 psi | 66% | 2720 fps | 99.6% |
| Rottweil R 903 | <<locked>> | 80% | 36,376 psi | 56% | 2628 fps | 98.2% |
| Rottweil R 907 | <<locked>> | 88% | 45,063 psi | 69% | 2776 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 84% | 38,421 psi | 59% | 2641 fps | 95.4% |
| Shooters World Match Rifle | <<locked>> | 80% | 45,600 psi | 70% | 2795 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 41,104 psi | 63% | 2700 fps | 99.5% |
| Shooters World SW4350 | <<locked>> | 88% | 41,379 psi | 64% | 2726 fps | 95% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 37,521 psi | 58% | 2680 fps | 97.7% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,804 psi | 72% | 2812 fps | 98.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 44,831 psi | 69% | 2789 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,644 psi | 72% | 2723 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,885 psi | 60% | 2582 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 43,207 psi | 66% | 2697 fps | 95.4% |
| Somchem S321 | <<locked>> | 80% | 52,837 psi | 81% | 2913 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 46,195 psi | 71% | 2720 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 46,775 psi | 72% | 2812 fps | 99.4% |
| Somchem S355 | <<locked>> | 80% | 37,188 psi | 57% | 2638 fps | 98.2% |
| Somchem S365 | <<locked>> | 80% | 26,992 psi | 42% | 2454 fps | 95.7% |
| Somchem S385 | <<locked>> | 98% | 46,166 psi | 71% | 2848 fps | 95.5% |
| Vihtavuori N130 | <<locked>> | 80% | 52,605 psi | 81% | 2782 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 47,094 psi | 72% | 2713 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,772 psi | 66% | 2700 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 43,337 psi | 67% | 2710 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,404 psi | 54% | 2572 fps | 98.9% |
| Vihtavuori N160 | <<locked>> | 82% | 33,808 psi | 52% | 2575 fps | 95.1% |
| Vihtavuori N530 | <<locked>> | 80% | 48,631 psi | 75% | 2828 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 41,684 psi | 64% | 2697 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 35,549 psi | 55% | 2631 fps | 95.5% |
| Vihtavuori N555 | <<locked>> | 90% | 32,169 psi | 49% | 2615 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,444 psi | 48% | 2493 fps | 96.5% |
| Winchester 748 | <<locked>> | 80% | 48,718 psi | 75% | 2874 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 42,511 psi | 65% | 2805 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 94% | 29,863 psi | 46% | 2615 fps | 95.9% |
| Winchester StaBALL Match | <<locked>> | 80% | 44,411 psi | 68% | 2792 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 117 powders for .280 Ackley Improved loaded with the .284 | 135gr | CutEdge ER Raptor. ReloadSwiss RS 60 delivers the highest muzzle velocity at 3,140 fps; across all powders the maximum-charge window runs from 1,831 fps to 3,140 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 55–90 %, leaving at least 10 % headroom. The 135.0 gr projectile in 0.284" calls for a 1:8.5 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. Alliant Power Pro 2000-MR, Alliant Reloder-17, ReloadSwiss RS 60 rank at the top here: for .280 Ackley Improved with the .284 | 135gr | CutEdge ER Raptor 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.