Load Specifications
Load data in caliber .243 Ackley Improved with .243 | 105gr | Remington SP Extended-Range bullet and 58 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Winchester StaBALL HD and Norma MRP.
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>> | 94% | 46,760 psi | 85% | 2828 fps | 98.9% |
| Accurate 4350 | <<locked>> | 86% | 48,385 psi | 88% | 2877 fps | 99.9% |
| Accurate High Country | <<locked>> | 92% | 47,718 psi | 86% | 2959 fps | 96% |
| ADI AR 2209 | <<locked>> | 92% | 49,487 psi | 90% | 2920 fps | 97.3% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 49,530 psi | 90% | 2913 fps | 97.4% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 49,530 psi | 90% | 2913 fps | 97.4% |
| Alliant Reloder-16 | <<locked>> | 88% | 49,487 psi | 90% | 2940 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 49,937 psi | 90% | 2953 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 48,921 psi | 89% | 2904 fps | 97.3% |
| Alliant Reloder-22 | <<locked>> | 96% | 49,951 psi | 90% | 2966 fps | 97.7% |
| Alliant Reloder-23 | <<locked>> | 96% | 47,108 psi | 85% | 2904 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 46,673 psi | 84% | 2940 fps | 99.6% |
| Alliant Reloder-26 | <<locked>> | 92% | 46,644 psi | 84% | 2969 fps | 99.8% |
| Bofors RP15 | <<locked>> | 98% | 48,834 psi | 88% | 2946 fps | 97.3% |
| Bofors RP5 | <<locked>> | 96% | 49,951 psi | 90% | 2966 fps | 97.7% |
| Bofors RP7 | <<locked>> | 84% | 48,950 psi | 89% | 2825 fps | 98.1% |
| Hodgdon H414 | <<locked>> | 84% | 47,195 psi | 85% | 2867 fps | 98.3% |
| Hodgdon H4350 | <<locked>> | 82% | 47,065 psi | 85% | 2828 fps | 97.1% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 49,588 psi | 90% | 2864 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 45,890 psi | 83% | 2979 fps | 97.4% |
| Hodgdon Superformance | <<locked>> | 86% | 49,995 psi | 90% | 2953 fps | 98.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,463 psi | 66% | 1850 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 49,748 psi | 90% | 2858 fps | 98.3% |
| IMR 4451 Enduron | <<locked>> | 82% | 47,384 psi | 86% | 2799 fps | 98.2% |
| IMR 4831 | <<locked>> | 88% | 49,095 psi | 89% | 2871 fps | 99.9% |
| Lovex S065 | <<locked>> | 84% | 47,427 psi | 86% | 2799 fps | 99.2% |
| Lovex S070 | <<locked>> | 86% | 48,849 psi | 88% | 2844 fps | 98.7% |
| Lovex S071ᴾ | <<locked>> | 100% | 47,761 psi | 86% | 2848 fps | 99.1% |
| Norma 204 | <<locked>> | 86% | 47,021 psi | 85% | 2848 fps | 96.6% |
| Norma MRP | <<locked>> | 94% | 49,342 psi | 89% | 2989 fps | 98.7% |
| Norma URP | <<locked>> | 86% | 47,674 psi | 86% | 2864 fps | 99.8% |
| Ramshot Grand | <<locked>> | 96% | 48,370 psi | 88% | 2949 fps | 96.2% |
| Ramshot Hunter | <<locked>> | 88% | 49,617 psi | 90% | 2917 fps | 99.3% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 49,980 psi | 90% | 2953 fps | 98.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,420 psi | 68% | 1896 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 49,443 psi | 89% | 2946 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 48,283 psi | 87% | 2897 fps | 99.8% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 46,601 psi | 84% | 2913 fps | 99.6% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 45,905 psi | 83% | 2972 fps | 98.5% |
| Rottweil R 903 | <<locked>> | 82% | 49,385 psi | 89% | 2841 fps | 100% |
| Rottweil R 905 | <<locked>> | 92% | 48,283 psi | 87% | 2894 fps | 97.3% |
| Rottweil R 907 | <<locked>> | 84% | 48,950 psi | 89% | 2825 fps | 98.1% |
| Shooters World Long Rifle | <<locked>> | 84% | 47,427 psi | 86% | 2799 fps | 99.2% |
| Shooters World SW4350 | <<locked>> | 86% | 48,849 psi | 88% | 2844 fps | 98.7% |
| SNPE Vectan Tubal 7000 | <<locked>> | 84% | 46,775 psi | 85% | 2746 fps | 98.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 47,863 psi | 87% | 2887 fps | 97.2% |
| Somchem S355 | <<locked>> | 82% | 49,545 psi | 90% | 2838 fps | 100% |
| Somchem S365 | <<locked>> | 88% | 46,717 psi | 85% | 2867 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 48,849 psi | 88% | 2871 fps | 98.1% |
| Vihtavuori N150 | <<locked>> | 82% | 47,340 psi | 86% | 2762 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 49,269 psi | 89% | 2858 fps | 99.9% |
| Vihtavuori N165 | <<locked>> | 96% | 48,341 psi | 87% | 2848 fps | 97.7% |
| Vihtavuori N550 | <<locked>> | 86% | 48,530 psi | 88% | 2861 fps | 99.8% |
| Vihtavuori N555 | <<locked>> | 94% | 49,603 psi | 90% | 2930 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 48,631 psi | 88% | 2825 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 47,195 psi | 85% | 2867 fps | 98.3% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 49,647 psi | 90% | 3081 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 48,443 psi | 88% | 2858 fps | 97.1% |
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>> | 84% | 33,185 psi | 60% | 2536 fps | 95.2% |
| Accurate 4350 | <<locked>> | 80% | 39,392 psi | 71% | 2700 fps | 98.8% |
| Accurate High Country | <<locked>> | 90% | 44,237 psi | 80% | 2887 fps | 95% |
| ADI AR 2209 | <<locked>> | 88% | 43,192 psi | 78% | 2792 fps | 95.6% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 43,598 psi | 79% | 2799 fps | 95.8% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 43,598 psi | 79% | 2799 fps | 95.8% |
| Alliant Reloder-16 | <<locked>> | 80% | 38,159 psi | 69% | 2710 fps | 98.8% |
| Alliant Reloder-17 | <<locked>> | 80% | 43,468 psi | 79% | 2838 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 43,105 psi | 78% | 2789 fps | 95.7% |
| Alliant Reloder-22 | <<locked>> | 90% | 40,669 psi | 74% | 2782 fps | 95.1% |
| Alliant Reloder-23 | <<locked>> | 80% | 28,181 psi | 51% | 2457 fps | 96.8% |
| Alliant Reloder-25 | <<locked>> | 88% | 31,720 psi | 57% | 2575 fps | 95% |
| Alliant Reloder-26 | 41.7 gr | 80% | 30,052 psi | 54% | 2566 fps | 95.1% |
| Bofors RP15 | <<locked>> | 94% | 42,902 psi | 78% | 2828 fps | 95.7% |
| Bofors RP5 | <<locked>> | 90% | 40,669 psi | 74% | 2782 fps | 95.1% |
| Bofors RP7 | <<locked>> | 80% | 43,178 psi | 78% | 2713 fps | 96.8% |
| Hodgdon H414 | <<locked>> | 80% | 41,205 psi | 75% | 2746 fps | 96.9% |
| Hodgdon H4350 | <<locked>> | 80% | 44,034 psi | 80% | 2766 fps | 96.3% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 35,621 psi | 64% | 2595 fps | 99.2% |
| Hodgdon Retumbo | <<locked>> | 96% | 40,161 psi | 73% | 2841 fps | 95.3% |
| Hodgdon Superformance | <<locked>> | 80% | 40,176 psi | 73% | 2756 fps | 96.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,427 psi | 50% | 1657 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 38,769 psi | 70% | 2638 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 80% | 44,396 psi | 80% | 2740 fps | 97.6% |
| IMR 4831 | <<locked>> | 80% | 37,623 psi | 68% | 2648 fps | 98.4% |
| Lovex S065 | <<locked>> | 80% | 42,163 psi | 76% | 2697 fps | 98.3% |
| Lovex S070 | <<locked>> | 80% | 40,364 psi | 73% | 2674 fps | 96.9% |
| Lovex S071 | <<locked>> | 88% | 32,489 psi | 59% | 2520 fps | 95% |
| Norma 204 | <<locked>> | 84% | 43,947 psi | 80% | 2785 fps | 95.8% |
| Norma MRP | 43.5 gr | 86% | 37,202 psi | 67% | 2730 fps | 95.4% |
| Norma URP | <<locked>> | 80% | 39,088 psi | 71% | 2694 fps | 98.6% |
| Ramshot Grand | <<locked>> | 94% | 45,049 psi | 82% | 2884 fps | 95.2% |
| Ramshot Hunter | <<locked>> | 80% | 37,956 psi | 69% | 2680 fps | 96.8% |
| Ramshot Magnum | <<locked>> | 94% | 40,030 psi | 72% | 2753 fps | 95.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,804 psi | 50% | 1693 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 46,137 psi | 83% | 2890 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 39,291 psi | 71% | 2720 fps | 98.5% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 37,768 psi | 68% | 2723 fps | 97.9% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 37,217 psi | 67% | 2762 fps | 95.3% |
| Rottweil R 903 | <<locked>> | 80% | 46,456 psi | 84% | 2789 fps | 100% |
| Rottweil R 905 | <<locked>> | 88% | 42,308 psi | 77% | 2772 fps | 95.7% |
| Rottweil R 907 | <<locked>> | 80% | 43,178 psi | 78% | 2713 fps | 96.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 42,163 psi | 76% | 2697 fps | 98.3% |
| Shooters World SW4350 | <<locked>> | 80% | 40,364 psi | 73% | 2674 fps | 96.9% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 41,220 psi | 75% | 2638 fps | 97% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 41,974 psi | 76% | 2769 fps | 95.6% |
| Somchem S355 | <<locked>> | 80% | 46,673 psi | 84% | 2785 fps | 100% |
| Somchem S365 | <<locked>> | 80% | 35,592 psi | 64% | 2648 fps | 99.9% |
| Somchem S385 | <<locked>> | 84% | 37,623 psi | 68% | 2641 fps | 95.1% |
| Vihtavuori N150 | <<locked>> | 80% | 44,541 psi | 81% | 2713 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 40,422 psi | 73% | 2690 fps | 98.8% |
| Vihtavuori N165 | <<locked>> | 90% | 39,392 psi | 71% | 2671 fps | 95.3% |
| Vihtavuori N550 | <<locked>> | 80% | 39,784 psi | 72% | 2690 fps | 98.6% |
| Vihtavuori N555 | <<locked>> | 80% | 31,053 psi | 56% | 2533 fps | 96.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 39,363 psi | 71% | 2654 fps | 99.9% |
| Winchester 760 | <<locked>> | 80% | 41,205 psi | 75% | 2746 fps | 96.9% |
| Winchester StaBALL HD | 40.1 gr | 80% | 24,903 psi | 45% | 2425 fps | 95.5% |
| Winchester Supreme 780 | <<locked>> | 90% | 42,119 psi | 76% | 2736 fps | 95.4% |
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 58 powders for .243 Ackley Improved loaded with the .243 | 105gr | Remington SP Extended-Range. Winchester StaBALL HD delivers the highest muzzle velocity at 3,081 fps; across all powders the maximum-charge window runs from 1,850 fps to 3,081 fps. Alliant Reloder-25 gives the best case fill at 100 %, and 58 of the 58 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 105.0 gr projectile in 0.243" calls for a 1:11.0 twist; slower twists will usually not stabilise this weight. Alliant Reloder-25, Hodgdon Retumbo, 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, Winchester StaBALL HD, Norma MRP rank at the top here: for .243 Ackley Improved with the .243 | 105gr | Remington SP Extended-Range 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.