Load Specifications
Load data in caliber .243 Ackley Improved with .243 | 100gr | Hornady SP bullet and 61 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Norma MRP and ReloadSwiss RS 70.
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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Max Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 98% | 49,922 psi | 90% | 2940 fps | 99% |
| Accurate 4350 | <<locked>> | 88% | 48,356 psi | 88% | 2936 fps | 99.6% |
| ADI AR 2208 | <<locked>> | 82% | 48,791 psi | 88% | 2874 fps | 99.8% |
| ADI AR 2209 | <<locked>> | 94% | 49,864 psi | 90% | 2976 fps | 96.7% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 49,777 psi | 90% | 2972 fps | 96.7% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 49,777 psi | 90% | 2972 fps | 96.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 49,313 psi | 89% | 2900 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 49,617 psi | 90% | 3002 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 84% | 46,833 psi | 85% | 2963 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 49,139 psi | 89% | 2966 fps | 96.7% |
| Alliant Reloder-22 | <<locked>> | 98% | 49,647 psi | 90% | 3022 fps | 97% |
| Alliant Reloder-23 | <<locked>> | 98% | 46,992 psi | 85% | 2963 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 43,714 psi | 79% | 2930 fps | 98.7% |
| Alliant Reloder-26 | <<locked>> | 96% | 49,980 psi | 90% | 3094 fps | 99.9% |
| Bofors RP15ᴾ | <<locked>> | 100% | 48,573 psi | 88% | 2999 fps | 96.6% |
| Bofors RP3 | <<locked>> | 82% | 49,603 psi | 90% | 2910 fps | 100% |
| Bofors RP5 | <<locked>> | 98% | 49,647 psi | 90% | 3022 fps | 97% |
| Bofors RP7 | <<locked>> | 86% | 49,313 psi | 89% | 2884 fps | 97.6% |
| Hodgdon H380 | <<locked>> | 82% | 49,893 psi | 90% | 2920 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 86% | 47,558 psi | 86% | 2930 fps | 97.8% |
| Hodgdon H4350 | <<locked>> | 84% | 47,572 psi | 86% | 2890 fps | 96.5% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 49,676 psi | 90% | 2927 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 46,746 psi | 85% | 2949 fps | 97.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,260 psi | 66% | 1883 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 47,152 psi | 85% | 2864 fps | 97.2% |
| IMR 4451 Enduron | <<locked>> | 84% | 48,051 psi | 87% | 2864 fps | 97.7% |
| IMR 4831 | <<locked>> | 90% | 49,139 psi | 89% | 2933 fps | 99.7% |
| Lovex S065 | <<locked>> | 86% | 48,051 psi | 87% | 2864 fps | 98.9% |
| Lovex S070 | <<locked>> | 88% | 49,110 psi | 89% | 2904 fps | 98.3% |
| Lovex S071ᴾ | <<locked>> | 100% | 44,498 psi | 81% | 2841 fps | 98% |
| Norma 204 | <<locked>> | 88% | 47,224 psi | 85% | 2907 fps | 95.9% |
| Norma MRP | <<locked>> | 96% | 49,008 psi | 89% | 3041 fps | 98.1% |
| Norma URP | <<locked>> | 88% | 47,718 psi | 86% | 2927 fps | 99.5% |
| Ramshot Hunter | <<locked>> | 90% | 49,719 psi | 90% | 2976 fps | 98.9% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 46,456 psi | 84% | 2933 fps | 96.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,898 psi | 67% | 1926 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 49,777 psi | 90% | 3018 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 48,530 psi | 88% | 2963 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 47,036 psi | 85% | 2979 fps | 99.3% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 42,815 psi | 77% | 2946 fps | 96.7% |
| Rottweil R 903 | <<locked>> | 84% | 49,792 psi | 90% | 2907 fps | 100% |
| Rottweil R 905 | <<locked>> | 94% | 48,399 psi | 88% | 2949 fps | 96.7% |
| Rottweil R 907 | <<locked>> | 86% | 49,313 psi | 89% | 2884 fps | 97.6% |
| Shooters World Long Rifle | <<locked>> | 86% | 48,051 psi | 87% | 2864 fps | 98.9% |
| Shooters World SW4350 | <<locked>> | 88% | 49,110 psi | 89% | 2904 fps | 98.3% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 48,051 psi | 87% | 2910 fps | 99.9% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 48,051 psi | 87% | 2756 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 47,485 psi | 86% | 2808 fps | 97.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 47,950 psi | 87% | 2943 fps | 96.5% |
| Somchem S355 | <<locked>> | 82% | 46,789 psi | 85% | 2851 fps | 100% |
| Somchem S365 | <<locked>> | 92% | 49,966 psi | 90% | 2986 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 48,994 psi | 89% | 2927 fps | 97.6% |
| Vihtavuori N150 | <<locked>> | 84% | 47,877 psi | 87% | 2831 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 49,414 psi | 89% | 2917 fps | 99.7% |
| Vihtavuori N165 | <<locked>> | 98% | 48,240 psi | 87% | 2897 fps | 97% |
| Vihtavuori N550 | <<locked>> | 88% | 48,965 psi | 89% | 2927 fps | 99.5% |
| Vihtavuori N555 | <<locked>> | 96% | 49,443 psi | 89% | 2989 fps | 99.9% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 48,878 psi | 88% | 2887 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 47,558 psi | 86% | 2930 fps | 97.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 45,324 psi | 82% | 3071 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 48,747 psi | 88% | 2913 fps | 96.4% |
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 3100 | <<locked>> | 88% | 35,346 psi | 64% | 2641 fps | 95.3% |
| Accurate 4350 | <<locked>> | 80% | 36,695 psi | 66% | 2694 fps | 97.6% |
| ADI AR 2208 | <<locked>> | 80% | 45,600 psi | 83% | 2815 fps | 99.6% |
| ADI AR 2209 | <<locked>> | 92% | 46,499 psi | 84% | 2913 fps | 95.8% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 43,685 psi | 79% | 2854 fps | 95.1% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 43,685 psi | 79% | 2854 fps | 95.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 46,064 psi | 83% | 2841 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,042 psi | 65% | 2710 fps | 97.7% |
| Alliant Reloder-17 | <<locked>> | 80% | 40,669 psi | 74% | 2841 fps | 99.7% |
| Alliant Reloder-19 | <<locked>> | 90% | 43,178 psi | 78% | 2844 fps | 95% |
| Alliant Reloder-22 | <<locked>> | 94% | 43,497 psi | 79% | 2897 fps | 95.2% |
| Alliant Reloder-23 | <<locked>> | 82% | 27,978 psi | 51% | 2500 fps | 95.9% |
| Alliant Reloder-25 | <<locked>> | 92% | 33,866 psi | 61% | 2684 fps | 95.2% |
| Alliant Reloder-26 | 42.9 gr | 84% | 32,169 psi | 58% | 2680 fps | 95.4% |
| Bofors RP15 | <<locked>> | 98% | 45,643 psi | 83% | 2940 fps | 95.8% |
| Bofors RP3 | <<locked>> | 80% | 46,586 psi | 84% | 2858 fps | 100% |
| Bofors RP5 | <<locked>> | 94% | 43,497 psi | 79% | 2897 fps | 95.2% |
| Bofors RP7 | <<locked>> | 80% | 40,828 psi | 74% | 2713 fps | 95.4% |
| Hodgdon H380 | <<locked>> | 80% | 46,934 psi | 85% | 2864 fps | 99.2% |
| Hodgdon H414 | <<locked>> | 80% | 38,667 psi | 70% | 2740 fps | 95.4% |
| Hodgdon H4350 | <<locked>> | 82% | 44,483 psi | 80% | 2828 fps | 95.7% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 33,446 psi | 61% | 2598 fps | 98.3% |
| Hodgdon Superformance | <<locked>> | 82% | 40,480 psi | 73% | 2812 fps | 95.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,079 psi | 49% | 1683 fps | 100% |
| IMR 4350 | <<locked>> | 84% | 41,553 psi | 75% | 2753 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 80% | 42,337 psi | 77% | 2749 fps | 96.4% |
| IMR 4831 | <<locked>> | 80% | 35,418 psi | 64% | 2648 fps | 97.2% |
| Lovex S065 | <<locked>> | 80% | 39,813 psi | 72% | 2697 fps | 97.1% |
| Lovex S070 | <<locked>> | 80% | 38,043 psi | 69% | 2674 fps | 95.4% |
| Lovex S071 | <<locked>> | 94% | 36,651 psi | 66% | 2674 fps | 95.8% |
| Norma 204 | <<locked>> | 86% | 44,092 psi | 80% | 2841 fps | 95% |
| Norma MRP | 44.7 gr | 90% | 40,016 psi | 72% | 2851 fps | 95.7% |
| Norma URP | <<locked>> | 80% | 36,535 psi | 66% | 2690 fps | 97.4% |
| Ramshot Hunter | <<locked>> | 80% | 35,578 psi | 64% | 2674 fps | 95.2% |
| Ramshot Magnum | <<locked>> | 98% | 43,178 psi | 78% | 2867 fps | 95.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,717 psi | 50% | 1726 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 43,207 psi | 78% | 2900 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 36,608 psi | 66% | 2713 fps | 97.2% |
| ReloadSwiss RS 70 | 40.5 gr | 80% | 35,505 psi | 64% | 2713 fps | 96.3% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 39,972 psi | 72% | 2874 fps | 95.5% |
| Rottweil R 903 | <<locked>> | 80% | 43,642 psi | 79% | 2795 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 92% | 45,092 psi | 82% | 2884 fps | 95.8% |
| Rottweil R 907 | <<locked>> | 80% | 40,828 psi | 74% | 2713 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 39,813 psi | 72% | 2697 fps | 97.1% |
| Shooters World SW4350 | <<locked>> | 80% | 38,043 psi | 69% | 2674 fps | 95.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 44,889 psi | 81% | 2851 fps | 99.8% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 45,136 psi | 82% | 2710 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 38,986 psi | 71% | 2638 fps | 95.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 44,672 psi | 81% | 2881 fps | 95.6% |
| Somchem S355 | <<locked>> | 80% | 44,034 psi | 80% | 2795 fps | 99.9% |
| Somchem S365 | <<locked>> | 80% | 32,996 psi | 60% | 2644 fps | 99.2% |
| Somchem S385 | <<locked>> | 88% | 40,190 psi | 73% | 2749 fps | 95.2% |
| Vihtavuori N150 | <<locked>> | 80% | 41,989 psi | 76% | 2723 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 37,884 psi | 69% | 2690 fps | 97.7% |
| Vihtavuori N165 | <<locked>> | 94% | 42,206 psi | 76% | 2782 fps | 95.4% |
| Vihtavuori N550 | <<locked>> | 80% | 37,594 psi | 68% | 2694 fps | 97.5% |
| Vihtavuori N555 | <<locked>> | 80% | 28,877 psi | 52% | 2526 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 37,144 psi | 67% | 2661 fps | 99.3% |
| Winchester 760 | <<locked>> | 80% | 38,928 psi | 70% | 2749 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 84% | 26,397 psi | 48% | 2523 fps | 95.6% |
| Winchester Supreme 780 | <<locked>> | 94% | 45,368 psi | 82% | 2851 fps | 95.6% |
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 61 powders for .243 Ackley Improved loaded with the .243 | 100gr | Hornady SP. Alliant Reloder-26 delivers the highest muzzle velocity at 3,094 fps; across all powders the maximum-charge window runs from 1,883 fps to 3,094 fps. Alliant Reloder-25 gives the best case fill at 100 %, and 61 of the 61 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (381 MPa), the top charges use 66–90 %, leaving at least 10 % headroom. The 100.0 gr projectile in 0.243" calls for a 1:9.5 twist; slower twists will usually not stabilise this weight. Alliant Reloder-25, Bofors RP15, Hodgdon TrailBoss 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 Reloder-26, Norma MRP, ReloadSwiss RS 70 rank at the top here: for .243 Ackley Improved with the .243 | 100gr | Hornady SP 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.