Load Specifications
Load data in caliber .280 Ackley Improved with .284 | 120gr | Speer Spitzer Soft Point bullet and 95 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Hodgdon Superformance 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>> | 82% | 55,912 psi | 86% | 3054 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 55,390 psi | 85% | 3081 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 56,739 psi | 87% | 3150 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 57,580 psi | 89% | 3133 fps | 97.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 46,369 psi | 71% | 3018 fps | 96.7% |
| Accurate 4064 | <<locked>> | 88% | 55,376 psi | 85% | 3130 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 55,912 psi | 86% | 3222 fps | 99.5% |
| ADI AR 2206H | <<locked>> | 86% | 58,726 psi | 90% | 3219 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 56,362 psi | 87% | 3163 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 84% | 57,493 psi | 88% | 3163 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 55,013 psi | 85% | 3084 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 55,100 psi | 85% | 3284 fps | 99.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 56,579 psi | 87% | 3182 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 57,130 psi | 88% | 3209 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 98% | 56,565 psi | 87% | 3281 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 94% | 58,407 psi | 90% | 3320 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 43,758 psi | 67% | 3048 fps | 99.3% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 49,806 psi | 77% | 3238 fps | 98.9% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 54,998 psi | 85% | 3169 fps | 99.5% |
| Bofors RP3 | <<locked>> | 90% | 57,551 psi | 89% | 3202 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 57,392 psi | 88% | 3173 fps | 97.4% |
| Hodgdon Benchmark | <<locked>> | 82% | 55,448 psi | 85% | 3091 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 57,276 psi | 88% | 3192 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 58,494 psi | 90% | 3219 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 96% | 58,465 psi | 90% | 3274 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 94% | 58,494 psi | 90% | 3228 fps | 97% |
| Hodgdon H4895 | <<locked>> | 84% | 55,738 psi | 86% | 3173 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 56,898 psi | 88% | 3202 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 55,666 psi | 86% | 3205 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 55,187 psi | 85% | 3245 fps | 97.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,795 psi | 55% | 1988 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 56,855 psi | 87% | 3173 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 55,811 psi | 86% | 3153 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 55,695 psi | 86% | 3143 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 86% | 55,259 psi | 85% | 3114 fps | 97.5% |
| IMR 4350 | <<locked>> | 98% | 57,754 psi | 89% | 3196 fps | 97.5% |
| IMR 4451 Enduron | <<locked>> | 92% | 55,622 psi | 86% | 3146 fps | 97.5% |
| IMR 4831 | <<locked>> | 98% | 56,376 psi | 87% | 3209 fps | 99.6% |
| IMR 4895 | <<locked>> | 88% | 58,624 psi | 90% | 3245 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 57,493 psi | 88% | 3163 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 55,114 psi | 85% | 3133 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 57,812 psi | 89% | 3136 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 55,622 psi | 86% | 3140 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 58,639 psi | 90% | 3196 fps | 99.1% |
| Lovex S070 | <<locked>> | 96% | 56,333 psi | 87% | 3179 fps | 98% |
| Norma 201 | <<locked>> | 86% | 57,435 psi | 88% | 3156 fps | 100% |
| Norma 202 | <<locked>> | 86% | 58,044 psi | 89% | 3156 fps | 100% |
| Norma 203B | <<locked>> | 88% | 56,347 psi | 87% | 3196 fps | 99.9% |
| Norma MRPᴾ | <<locked>> | 100% | 49,066 psi | 75% | 3182 fps | 96.2% |
| Norma URP | <<locked>> | 98% | 58,363 psi | 90% | 3261 fps | 99.7% |
| Ramshot Big Game | <<locked>> | 88% | 57,217 psi | 88% | 3222 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 98% | 57,348 psi | 88% | 3261 fps | 98.7% |
| Ramshot TAC | <<locked>> | 84% | 57,972 psi | 89% | 3182 fps | 99.1% |
| Ramshot Wild Boar | <<locked>> | 84% | 57,682 psi | 89% | 3199 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 58,291 psi | 90% | 3159 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,289 psi | 56% | 2034 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 58,334 psi | 90% | 3192 fps | 98.6% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 57,943 psi | 89% | 3284 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 57,827 psi | 89% | 3317 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 55,782 psi | 86% | 3241 fps | 99.4% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 58,653 psi | 90% | 3333 fps | 99.6% |
| Rottweil R 901 | <<locked>> | 84% | 58,218 psi | 90% | 3140 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 57,827 psi | 89% | 3153 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 57,334 psi | 88% | 3192 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 57,392 psi | 88% | 3173 fps | 97.4% |
| Shooters World Long Rifle | <<locked>> | 96% | 58,639 psi | 90% | 3196 fps | 99.1% |
| Shooters World Match Rifle | <<locked>> | 84% | 55,114 psi | 85% | 3133 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 55,622 psi | 86% | 3140 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 56,333 psi | 87% | 3179 fps | 98% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 55,593 psi | 86% | 3202 fps | 99.9% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 56,623 psi | 87% | 3159 fps | 99.2% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 57,159 psi | 88% | 3182 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 58,378 psi | 90% | 3087 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 55,593 psi | 86% | 3035 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 55,303 psi | 85% | 3087 fps | 97.6% |
| Somchem S335 | <<locked>> | 86% | 58,088 psi | 89% | 3084 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 56,057 psi | 86% | 3146 fps | 99.9% |
| Somchem S355 | <<locked>> | 92% | 57,537 psi | 89% | 3189 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 56,855 psi | 87% | 3264 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 52,518 psi | 81% | 3133 fps | 96.5% |
| Vihtavuori N130 | <<locked>> | 82% | 58,015 psi | 89% | 3048 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 58,682 psi | 90% | 3071 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 57,943 psi | 89% | 3117 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 58,711 psi | 90% | 3133 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 55,376 psi | 85% | 3110 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 57,159 psi | 88% | 3202 fps | 99.6% |
| Vihtavuori N530 | <<locked>> | 84% | 58,102 psi | 89% | 3163 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 56,768 psi | 87% | 3123 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 56,086 psi | 86% | 3202 fps | 99.4% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 48,544 psi | 75% | 3133 fps | 99.1% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 57,246 psi | 88% | 3173 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 58,392 psi | 90% | 3212 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 58,769 psi | 90% | 3281 fps | 98.3% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 39,305 psi | 60% | 3058 fps | 99.4% |
| Winchester StaBALL Match | <<locked>> | 86% | 57,276 psi | 88% | 3192 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% | 52,373 psi | 81% | 3002 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 45,498 psi | 70% | 2923 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 52,895 psi | 81% | 3091 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 50,459 psi | 78% | 3009 fps | 95.7% |
| Accurate 3100 | <<locked>> | 98% | 43,250 psi | 67% | 2953 fps | 95.8% |
| Accurate 4064 | <<locked>> | 80% | 43,033 psi | 66% | 2913 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 36,753 psi | 57% | 2835 fps | 95.6% |
| ADI AR 2206H | <<locked>> | 80% | 48,573 psi | 75% | 3041 fps | 99.4% |
| ADI AR 2208 | <<locked>> | 80% | 41,307 psi | 64% | 2871 fps | 97.6% |
| ADI Benchmark 8208 | <<locked>> | 80% | 50,618 psi | 78% | 3048 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 51,634 psi | 79% | 3031 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 44,701 psi | 69% | 3077 fps | 98.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 41,118 psi | 63% | 2897 fps | 98.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 44,208 psi | 68% | 2969 fps | 98.4% |
| Alliant Reloder-16 | <<locked>> | 84% | 36,376 psi | 56% | 2848 fps | 95.6% |
| Alliant Reloder-17 | <<locked>> | 80% | 35,766 psi | 55% | 2861 fps | 97.2% |
| Alliant Reloder-23 | <<locked>> | 90% | 31,763 psi | 49% | 2736 fps | 95.4% |
| Alliant Reloder-26 | <<locked>> | 92% | 37,202 psi | 57% | 2943 fps | 95.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 47,993 psi | 74% | 3041 fps | 98.6% |
| Bofors RP3 | <<locked>> | 80% | 41,046 psi | 63% | 2900 fps | 98.9% |
| Bofors RP7 | <<locked>> | 88% | 47,326 psi | 73% | 2989 fps | 95.1% |
| Hodgdon Benchmark | <<locked>> | 80% | 52,083 psi | 80% | 3035 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 50,140 psi | 77% | 3074 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 41,785 psi | 64% | 2904 fps | 96.6% |
| Hodgdon H414 | <<locked>> | 88% | 44,788 psi | 69% | 3018 fps | 95.2% |
| Hodgdon H4350 | <<locked>> | 90% | 51,517 psi | 79% | 3107 fps | 95.5% |
| Hodgdon H4895 | <<locked>> | 80% | 49,052 psi | 75% | 3054 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 31,299 psi | 48% | 2671 fps | 95.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 45,324 psi | 70% | 3022 fps | 99.5% |
| Hodgdon Superformance | 64.8 gr | 90% | 47,688 psi | 73% | 3100 fps | 95.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,629 psi | 41% | 1778 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 46,934 psi | 72% | 2995 fps | 99.4% |
| IMR 3031 | <<locked>> | 80% | 48,965 psi | 75% | 3045 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 43,381 psi | 67% | 2913 fps | 98.3% |
| IMR 4166 Enduron | <<locked>> | 80% | 45,759 psi | 70% | 2933 fps | 95.4% |
| IMR 4350 | <<locked>> | 92% | 47,950 psi | 74% | 3018 fps | 95.4% |
| IMR 4451 Enduron | <<locked>> | 86% | 46,064 psi | 71% | 2966 fps | 95.3% |
| IMR 4831 | <<locked>> | 84% | 35,375 psi | 54% | 2782 fps | 95.1% |
| IMR 4895 | <<locked>> | 80% | 45,281 psi | 70% | 3002 fps | 99% |
| IMR 8208 XBR | <<locked>> | 80% | 50,618 psi | 78% | 3048 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 48,341 psi | 74% | 3018 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 48,138 psi | 74% | 2969 fps | 99.4% |
| Lovex S062 | <<locked>> | 80% | 43,439 psi | 67% | 2917 fps | 99.5% |
| Lovex S065 | <<locked>> | 84% | 40,480 psi | 62% | 2848 fps | 95.3% |
| Lovex S070 | <<locked>> | 88% | 43,874 psi | 67% | 2940 fps | 95.1% |
| Norma 201 | <<locked>> | 80% | 47,630 psi | 73% | 2989 fps | 99.8% |
| Norma 202 | <<locked>> | 80% | 47,863 psi | 74% | 2992 fps | 100% |
| Norma 203B | <<locked>> | 80% | 43,569 psi | 67% | 2956 fps | 98.7% |
| Norma MRP | <<locked>> | 98% | 45,716 psi | 70% | 3110 fps | 95.2% |
| Norma URP | <<locked>> | 84% | 36,753 psi | 57% | 2835 fps | 95.4% |
| Ramshot Big Game | <<locked>> | 80% | 43,497 psi | 67% | 2969 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 90% | 43,772 psi | 67% | 3005 fps | 95.9% |
| Ramshot TAC | <<locked>> | 80% | 50,792 psi | 78% | 3058 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 80% | 50,357 psi | 77% | 3074 fps | 99.5% |
| Ramshot X-Terminator | <<locked>> | 80% | 54,607 psi | 84% | 3100 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,137 psi | 42% | 1824 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 42,105 psi | 65% | 2884 fps | 95% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 47,137 psi | 73% | 3091 fps | 98.8% |
| ReloadSwiss RS 60 | 54.5 gr | 80% | 38,058 psi | 59% | 2933 fps | 99.6% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 36,463 psi | 56% | 2848 fps | 95% |
| ReloadSwiss RS 70 | 59.5 gr | 86% | 38,638 psi | 59% | 2917 fps | 95.1% |
| Rottweil R 901 | <<locked>> | 80% | 51,532 psi | 79% | 3035 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 45,165 psi | 69% | 2933 fps | 99.6% |
| Rottweil R 903 | <<locked>> | 80% | 38,638 psi | 59% | 2838 fps | 98.2% |
| Rottweil R 907 | <<locked>> | 88% | 47,326 psi | 73% | 2989 fps | 95.1% |
| Shooters World Long Rifle | <<locked>> | 84% | 40,480 psi | 62% | 2848 fps | 95.3% |
| Shooters World Match Rifle | <<locked>> | 80% | 48,341 psi | 74% | 3018 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 43,439 psi | 67% | 2917 fps | 99.5% |
| Shooters World SW4350 | <<locked>> | 88% | 43,874 psi | 67% | 2940 fps | 95.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 39,755 psi | 61% | 2894 fps | 97.7% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 49,313 psi | 76% | 3031 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 47,079 psi | 72% | 3005 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 48,675 psi | 75% | 2936 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 40,785 psi | 63% | 2785 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 45,455 psi | 70% | 2907 fps | 95.4% |
| Somchem S335 | <<locked>> | 80% | 48,385 psi | 74% | 2933 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 48,820 psi | 75% | 3022 fps | 99.4% |
| Somchem S355 | <<locked>> | 80% | 39,421 psi | 61% | 2848 fps | 98.2% |
| Somchem S365 | <<locked>> | 80% | 28,819 psi | 44% | 2654 fps | 95.8% |
| Somchem S385 | <<locked>> | 98% | 49,182 psi | 76% | 3071 fps | 95.7% |
| Vihtavuori N130 | <<locked>> | 80% | 54,694 psi | 84% | 2999 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 49,081 psi | 76% | 2927 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 45,049 psi | 69% | 2913 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 45,368 psi | 70% | 2920 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 37,449 psi | 58% | 2772 fps | 98.8% |
| Vihtavuori N160 | <<locked>> | 82% | 35,868 psi | 55% | 2779 fps | 95% |
| Vihtavuori N530 | <<locked>> | 80% | 50,734 psi | 78% | 3045 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 43,859 psi | 67% | 2907 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 37,869 psi | 58% | 2838 fps | 95.6% |
| Vihtavuori N555 | <<locked>> | 90% | 34,664 psi | 53% | 2825 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 33,141 psi | 51% | 2684 fps | 96.5% |
| Winchester 748 | <<locked>> | 80% | 51,039 psi | 79% | 3097 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 44,788 psi | 69% | 3018 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 94% | 32,198 psi | 50% | 2835 fps | 96.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 46,746 psi | 72% | 3009 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 115 powders for .280 Ackley Improved loaded with the .284 | 120gr | Speer Spitzer Soft Point. ReloadSwiss RS 70 delivers the highest muzzle velocity at 3,333 fps; across all powders the maximum-charge window runs from 1,988 fps to 3,333 fps. Accurate 3100 gives the best case fill at 100 %, and 115 of the 115 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 120.0 gr projectile in 0.284" calls for a 1:14.5 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 70, Hodgdon Superformance, ReloadSwiss RS 60 rank at the top here: for .280 Ackley Improved with the .284 | 120gr | Speer Spitzer Soft Point 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.