Load Specifications
Load data in caliber .243 Ackley Improved with .243 | 105gr | Geco SOFTPOINT bullet and 56 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>> | 96% | 49,617 psi | 90% | 2874 fps | 99.3% |
| Accurate 4350 | <<locked>> | 86% | 48,109 psi | 87% | 2867 fps | 99.8% |
| ADI AR 2209 | <<locked>> | 92% | 49,240 psi | 89% | 2913 fps | 97.2% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 49,284 psi | 89% | 2907 fps | 97.3% |
| Alliant Reloder-16 | <<locked>> | 88% | 49,226 psi | 89% | 2933 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 49,647 psi | 90% | 2946 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 48,675 psi | 88% | 2900 fps | 97.2% |
| Alliant Reloder-22 | <<locked>> | 96% | 49,647 psi | 90% | 2963 fps | 97.6% |
| Alliant Reloder-23 | <<locked>> | 96% | 46,847 psi | 85% | 2897 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 46,427 psi | 84% | 2933 fps | 99.6% |
| Alliant Reloder-26 | <<locked>> | 94% | 49,864 psi | 90% | 3028 fps | 100% |
| Bofors RP15 | <<locked>> | 98% | 48,617 psi | 88% | 2940 fps | 97.2% |
| Bofors RP5 | <<locked>> | 96% | 49,647 psi | 90% | 2963 fps | 97.6% |
| Bofors RP7 | <<locked>> | 84% | 48,704 psi | 88% | 2822 fps | 98% |
| Hodgdon H414 | <<locked>> | 84% | 46,905 psi | 85% | 2861 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 84% | 49,966 psi | 90% | 2881 fps | 97.7% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 49,342 psi | 89% | 2858 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 45,426 psi | 82% | 2966 fps | 97.3% |
| Hodgdon Superformance | <<locked>> | 86% | 49,748 psi | 90% | 2946 fps | 98.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,666 psi | 66% | 1850 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 49,835 psi | 90% | 2858 fps | 98.3% |
| IMR 4451 Enduron | <<locked>> | 82% | 47,137 psi | 85% | 2792 fps | 98.1% |
| IMR 4831 | <<locked>> | 88% | 48,820 psi | 88% | 2867 fps | 99.9% |
| Lovex S065 | <<locked>> | 84% | 47,500 psi | 86% | 2799 fps | 99.2% |
| Lovex S070 | <<locked>> | 86% | 48,588 psi | 88% | 2838 fps | 98.6% |
| Lovex S071ᴾ | <<locked>> | 100% | 47,514 psi | 86% | 2841 fps | 99% |
| Norma 204 | <<locked>> | 86% | 46,804 psi | 85% | 2841 fps | 96.5% |
| Norma MRP | <<locked>> | 94% | 49,110 psi | 89% | 2986 fps | 98.7% |
| Norma URP | <<locked>> | 86% | 47,398 psi | 86% | 2861 fps | 99.8% |
| Ramshot Grand | <<locked>> | 96% | 48,138 psi | 87% | 2943 fps | 96.1% |
| Ramshot Hunter | <<locked>> | 88% | 49,356 psi | 89% | 2910 fps | 99.2% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 49,806 psi | 90% | 2946 fps | 98.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,318 psi | 68% | 1893 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 49,168 psi | 89% | 2943 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 47,993 psi | 87% | 2890 fps | 99.7% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 49,937 psi | 90% | 2976 fps | 99.9% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 45,759 psi | 83% | 2966 fps | 98.4% |
| Rottweil R 903 | <<locked>> | 82% | 49,385 psi | 89% | 2838 fps | 100% |
| Rottweil R 905 | <<locked>> | 92% | 48,022 psi | 87% | 2887 fps | 97.2% |
| Rottweil R 907 | <<locked>> | 84% | 48,704 psi | 88% | 2822 fps | 98% |
| Shooters World Long Rifle | <<locked>> | 84% | 47,500 psi | 86% | 2799 fps | 99.2% |
| Shooters World SW4350 | <<locked>> | 86% | 48,588 psi | 88% | 2838 fps | 98.6% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 49,734 psi | 90% | 2795 fps | 98.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 47,587 psi | 86% | 2881 fps | 97.1% |
| Somchem S355 | <<locked>> | 82% | 49,226 psi | 89% | 2831 fps | 100% |
| Somchem S365 | <<locked>> | 90% | 49,821 psi | 90% | 2920 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 48,602 psi | 88% | 2864 fps | 98.1% |
| Vihtavuori N150 | <<locked>> | 82% | 47,369 psi | 86% | 2762 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 48,965 psi | 89% | 2851 fps | 99.8% |
| Vihtavuori N165 | <<locked>> | 96% | 47,776 psi | 86% | 2838 fps | 97.5% |
| Vihtavuori N550 | <<locked>> | 86% | 48,240 psi | 87% | 2854 fps | 99.7% |
| Vihtavuori N555 | <<locked>> | 94% | 49,313 psi | 89% | 2927 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 48,385 psi | 88% | 2822 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 47,210 psi | 85% | 2867 fps | 98.3% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 49,313 psi | 89% | 3077 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 48,225 psi | 87% | 2851 fps | 97% |
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% | 39,102 psi | 71% | 2694 fps | 98.7% |
| ADI AR 2209 | <<locked>> | 88% | 43,279 psi | 78% | 2792 fps | 95.6% |
| Alliant Power Pro Varmint | <<locked>> | 88% | 43,366 psi | 78% | 2792 fps | 95.7% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,884 psi | 69% | 2703 fps | 98.8% |
| Alliant Reloder-17 | <<locked>> | 80% | 43,149 psi | 78% | 2831 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 88% | 42,888 psi | 78% | 2785 fps | 95.7% |
| Alliant Reloder-22 | <<locked>> | 90% | 40,437 psi | 73% | 2772 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,949 psi | 51% | 2451 fps | 96.7% |
| Alliant Reloder-25 | <<locked>> | 88% | 31,763 psi | 57% | 2575 fps | 95% |
| Alliant Reloder-26 | 41.5 gr | 80% | 29,849 psi | 54% | 2559 fps | 95% |
| Bofors RP15 | <<locked>> | 94% | 42,670 psi | 77% | 2822 fps | 95.6% |
| Bofors RP5 | <<locked>> | 90% | 40,437 psi | 73% | 2772 fps | 95% |
| Bofors RP7 | <<locked>> | 80% | 42,888 psi | 78% | 2707 fps | 96.7% |
| Hodgdon H414 | <<locked>> | 80% | 40,944 psi | 74% | 2740 fps | 96.8% |
| Hodgdon H4350 | <<locked>> | 80% | 43,787 psi | 79% | 2759 fps | 96.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 35,636 psi | 64% | 2595 fps | 99.2% |
| Hodgdon Retumbo | <<locked>> | 96% | 39,958 psi | 72% | 2835 fps | 95.2% |
| Hodgdon Superformance | <<locked>> | 80% | 39,943 psi | 72% | 2749 fps | 96.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,296 psi | 49% | 1654 fps | 100% |
| IMR 4350 | <<locked>> | 80% | 38,508 psi | 70% | 2631 fps | 95.4% |
| IMR 4451 Enduron | <<locked>> | 80% | 44,425 psi | 80% | 2740 fps | 97.5% |
| IMR 4831 | <<locked>> | 80% | 37,652 psi | 68% | 2648 fps | 98.4% |
| Lovex S065 | <<locked>> | 80% | 41,930 psi | 76% | 2687 fps | 98.2% |
| Lovex S070 | <<locked>> | 80% | 40,118 psi | 73% | 2667 fps | 96.8% |
| Lovex S071 | <<locked>> | 90% | 34,374 psi | 62% | 2566 fps | 95.7% |
| Norma 204 | <<locked>> | 84% | 43,685 psi | 79% | 2782 fps | 95.7% |
| Norma MRP | 43.3 gr | 86% | 36,970 psi | 67% | 2723 fps | 95.3% |
| Norma URP | <<locked>> | 80% | 38,812 psi | 70% | 2687 fps | 98.5% |
| Ramshot Grand | <<locked>> | 94% | 44,831 psi | 81% | 2877 fps | 95.1% |
| Ramshot Hunter | <<locked>> | 80% | 37,724 psi | 68% | 2674 fps | 96.7% |
| Ramshot Magnum | <<locked>> | 94% | 39,813 psi | 72% | 2746 fps | 95.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,949 psi | 51% | 1696 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 45,861 psi | 83% | 2884 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 39,001 psi | 71% | 2710 fps | 98.4% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 37,565 psi | 68% | 2717 fps | 97.8% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 36,811 psi | 67% | 2746 fps | 95% |
| Rottweil R 903 | <<locked>> | 80% | 46,137 psi | 83% | 2782 fps | 100% |
| Rottweil R 905 | <<locked>> | 88% | 42,090 psi | 76% | 2769 fps | 95.6% |
| Rottweil R 907 | <<locked>> | 80% | 42,888 psi | 78% | 2707 fps | 96.7% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,930 psi | 76% | 2687 fps | 98.2% |
| Shooters World SW4350 | <<locked>> | 80% | 40,118 psi | 73% | 2667 fps | 96.8% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,988 psi | 74% | 2631 fps | 96.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 41,713 psi | 75% | 2762 fps | 95.4% |
| Somchem S355 | <<locked>> | 80% | 46,383 psi | 84% | 2782 fps | 100% |
| Somchem S365 | <<locked>> | 80% | 35,288 psi | 64% | 2644 fps | 99.8% |
| Somchem S385 | <<locked>> | 84% | 37,405 psi | 68% | 2635 fps | 95% |
| Vihtavuori N150 | <<locked>> | 80% | 44,266 psi | 80% | 2707 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 40,147 psi | 73% | 2684 fps | 98.8% |
| Vihtavuori N165 | <<locked>> | 90% | 39,436 psi | 71% | 2674 fps | 95.3% |
| Vihtavuori N550 | <<locked>> | 80% | 39,769 psi | 72% | 2690 fps | 98.5% |
| Vihtavuori N555 | <<locked>> | 80% | 31,024 psi | 56% | 2533 fps | 96.8% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 39,378 psi | 71% | 2654 fps | 99.9% |
| Winchester 760 | <<locked>> | 80% | 41,234 psi | 75% | 2746 fps | 96.9% |
| Winchester StaBALL HD | 39.9 gr | 80% | 24,714 psi | 45% | 2418 fps | 95.3% |
| Winchester Supreme 780 | <<locked>> | 90% | 41,901 psi | 76% | 2730 fps | 95.3% |
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 56 powders for .243 Ackley Improved loaded with the .243 | 105gr | Geco SOFTPOINT. Winchester StaBALL HD delivers the highest muzzle velocity at 3,077 fps; across all powders the maximum-charge window runs from 1,850 fps to 3,077 fps. Alliant Reloder-25 gives the best case fill at 100 %, and 56 of the 56 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 | Geco SOFTPOINT 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.