Load Specifications
Load data in caliber .243 Ackley Improved with .2425 | 100gr | Prvi Partizan SP bullet and 57 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>> | 96% | 47,718 psi | 86% | 2904 fps | 98.7% |
| Accurate 4350 | <<locked>> | 88% | 49,443 psi | 89% | 2956 fps | 99.8% |
| ADI AR 2208 | <<locked>> | 82% | 49,168 psi | 89% | 2887 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 92% | 47,340 psi | 86% | 2936 fps | 96.2% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 47,355 psi | 86% | 2930 fps | 96.3% |
| Alliant Reloder-16 | <<locked>> | 88% | 47,268 psi | 86% | 2963 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 84% | 47,848 psi | 87% | 2982 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 46,775 psi | 85% | 2920 fps | 96.1% |
| Alliant Reloder-22 | <<locked>> | 96% | 47,485 psi | 86% | 2982 fps | 96.5% |
| Alliant Reloder-23 | <<locked>> | 98% | 47,935 psi | 87% | 2982 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 44,469 psi | 80% | 2949 fps | 98.9% |
| Alliant Reloder-26 | <<locked>> | 94% | 47,384 psi | 86% | 3048 fps | 99.7% |
| Bofors RP15ᴾ | <<locked>> | 100% | 49,792 psi | 90% | 3022 fps | 96.9% |
| Bofors RP5 | <<locked>> | 96% | 47,485 psi | 86% | 2982 fps | 96.5% |
| Bofors RP7 | <<locked>> | 84% | 47,050 psi | 85% | 2848 fps | 97.2% |
| Hodgdon H414 | <<locked>> | 86% | 48,182 psi | 87% | 2946 fps | 98% |
| Hodgdon H4350 | <<locked>> | 84% | 48,225 psi | 87% | 2907 fps | 96.8% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 47,282 psi | 86% | 2890 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 47,572 psi | 86% | 2969 fps | 97.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,477 psi | 66% | 1893 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 48,037 psi | 87% | 2887 fps | 97.5% |
| IMR 4451 Enduron | <<locked>> | 84% | 48,689 psi | 88% | 2881 fps | 98% |
| IMR 4831 | <<locked>> | 88% | 46,833 psi | 85% | 2894 fps | 99.6% |
| Lovex S065 | <<locked>> | 86% | 48,646 psi | 88% | 2881 fps | 99% |
| Lovex S070 | <<locked>> | 88% | 49,734 psi | 90% | 2920 fps | 98.4% |
| Lovex S071ᴾ | <<locked>> | 100% | 45,397 psi | 82% | 2861 fps | 98.3% |
| Norma 204 | <<locked>> | 88% | 48,138 psi | 87% | 2927 fps | 96.3% |
| Norma MRP | <<locked>> | 94% | 46,833 psi | 85% | 3002 fps | 97.8% |
| Norma URP | <<locked>> | 88% | 48,414 psi | 88% | 2943 fps | 99.6% |
| Ramshot Hunter | <<locked>> | 88% | 47,369 psi | 86% | 2936 fps | 98.6% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 47,485 psi | 86% | 2959 fps | 97.2% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,101 psi | 67% | 1936 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 47,094 psi | 85% | 2976 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 49,153 psi | 89% | 2976 fps | 99.6% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 47,921 psi | 87% | 2999 fps | 99.5% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 43,700 psi | 79% | 2972 fps | 97.2% |
| Rottweil R 903 | <<locked>> | 82% | 47,543 psi | 86% | 2874 fps | 100% |
| Rottweil R 905 | <<locked>> | 94% | 49,342 psi | 89% | 2969 fps | 97% |
| Rottweil R 907 | <<locked>> | 84% | 47,050 psi | 85% | 2848 fps | 97.2% |
| Shooters World Long Rifle | <<locked>> | 86% | 48,646 psi | 88% | 2881 fps | 99% |
| Shooters World SW4350 | <<locked>> | 88% | 49,734 psi | 90% | 2920 fps | 98.4% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 48,762 psi | 88% | 2927 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 48,805 psi | 88% | 2772 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 48,066 psi | 87% | 2825 fps | 98% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 48,907 psi | 89% | 2966 fps | 96.8% |
| Somchem S355 | <<locked>> | 82% | 47,529 psi | 86% | 2867 fps | 100% |
| Somchem S365 | <<locked>> | 90% | 47,572 psi | 86% | 2949 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 49,864 psi | 90% | 2946 fps | 97.8% |
| Vihtavuori N150 | <<locked>> | 84% | 48,544 psi | 88% | 2844 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 47,079 psi | 85% | 2881 fps | 99.5% |
| Vihtavuori N165 | <<locked>> | 98% | 49,052 psi | 89% | 2917 fps | 97.3% |
| Vihtavuori N550 | <<locked>> | 88% | 49,545 psi | 90% | 2943 fps | 99.6% |
| Vihtavuori N555 | <<locked>> | 94% | 47,094 psi | 85% | 2953 fps | 99.8% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 49,719 psi | 90% | 2904 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 48,544 psi | 88% | 2953 fps | 98.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 46,456 psi | 84% | 3097 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 49,588 psi | 90% | 2933 fps | 96.8% |
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% | 36,201 psi | 66% | 2664 fps | 95.8% |
| Accurate 4350 | <<locked>> | 80% | 37,376 psi | 68% | 2713 fps | 97.8% |
| ADI AR 2208 | <<locked>> | 80% | 46,311 psi | 84% | 2835 fps | 99.7% |
| ADI AR 2209 | <<locked>> | 90% | 44,237 psi | 80% | 2871 fps | 95.3% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 44,556 psi | 81% | 2874 fps | 95.5% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,448 psi | 66% | 2723 fps | 97.9% |
| Alliant Reloder-17 | <<locked>> | 80% | 41,336 psi | 75% | 2854 fps | 99.8% |
| Alliant Reloder-19 | <<locked>> | 90% | 44,048 psi | 80% | 2867 fps | 95.4% |
| Alliant Reloder-22 | <<locked>> | 94% | 44,324 psi | 80% | 2917 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 80% | 26,803 psi | 49% | 2461 fps | 95.3% |
| Alliant Reloder-25 | <<locked>> | 92% | 34,534 psi | 62% | 2707 fps | 95.6% |
| Alliant Reloder-26 | 43.6 gr | 84% | 32,880 psi | 60% | 2703 fps | 95.8% |
| Bofors RP15 | <<locked>> | 96% | 43,700 psi | 79% | 2904 fps | 95.3% |
| Bofors RP5 | <<locked>> | 94% | 44,324 psi | 80% | 2917 fps | 95.6% |
| Bofors RP7 | <<locked>> | 80% | 41,466 psi | 75% | 2733 fps | 95.7% |
| Hodgdon H414 | <<locked>> | 80% | 39,305 psi | 71% | 2759 fps | 95.7% |
| Hodgdon H4350 | <<locked>> | 80% | 42,467 psi | 77% | 2789 fps | 95.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 34,084 psi | 62% | 2615 fps | 98.5% |
| Hodgdon Superformance | <<locked>> | 82% | 41,292 psi | 75% | 2835 fps | 95.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,137 psi | 49% | 1690 fps | 100% |
| IMR 4350 | <<locked>> | 82% | 39,668 psi | 72% | 2713 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 80% | 42,989 psi | 78% | 2769 fps | 96.7% |
| IMR 4831 | <<locked>> | 80% | 36,071 psi | 65% | 2667 fps | 97.5% |
| Lovex S065 | <<locked>> | 80% | 40,466 psi | 73% | 2717 fps | 97.4% |
| Lovex S070 | <<locked>> | 80% | 38,653 psi | 70% | 2690 fps | 95.7% |
| Lovex S071 | <<locked>> | 92% | 34,911 psi | 63% | 2635 fps | 95.3% |
| Norma 204 | <<locked>> | 86% | 44,962 psi | 81% | 2864 fps | 95.4% |
| Norma MRP | 45.4 gr | 90% | 40,799 psi | 74% | 2871 fps | 96% |
| Norma URP | <<locked>> | 80% | 37,231 psi | 67% | 2710 fps | 97.7% |
| Ramshot Hunter | <<locked>> | 80% | 36,143 psi | 65% | 2694 fps | 95.6% |
| Ramshot Magnum | <<locked>> | 96% | 40,857 psi | 74% | 2822 fps | 95.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,760 psi | 50% | 1732 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 43,932 psi | 80% | 2913 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 37,275 psi | 67% | 2730 fps | 97.5% |
| ReloadSwiss RS 70 | 41.2 gr | 80% | 36,303 psi | 66% | 2736 fps | 96.8% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 40,553 psi | 73% | 2897 fps | 95.9% |
| Rottweil R 903 | <<locked>> | 80% | 44,411 psi | 80% | 2815 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 90% | 42,917 psi | 78% | 2844 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 80% | 41,466 psi | 75% | 2733 fps | 95.7% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,466 psi | 73% | 2717 fps | 97.4% |
| Shooters World SW4350 | <<locked>> | 80% | 38,653 psi | 70% | 2690 fps | 95.7% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 45,585 psi | 82% | 2871 fps | 99.8% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 45,571 psi | 82% | 2720 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 39,537 psi | 72% | 2654 fps | 95.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 42,511 psi | 77% | 2838 fps | 95.1% |
| Somchem S355 | <<locked>> | 80% | 44,744 psi | 81% | 2815 fps | 99.9% |
| Somchem S365 | <<locked>> | 80% | 33,692 psi | 61% | 2661 fps | 99.4% |
| Somchem S385 | <<locked>> | 88% | 41,031 psi | 74% | 2772 fps | 95.6% |
| Vihtavuori N150 | <<locked>> | 80% | 42,670 psi | 77% | 2740 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 38,566 psi | 70% | 2710 fps | 98% |
| Vihtavuori N165 | <<locked>> | 94% | 43,018 psi | 78% | 2802 fps | 95.8% |
| Vihtavuori N550 | <<locked>> | 80% | 38,218 psi | 69% | 2710 fps | 97.7% |
| Vihtavuori N555 | <<locked>> | 80% | 29,530 psi | 53% | 2546 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 37,913 psi | 69% | 2680 fps | 99.5% |
| Winchester 760 | <<locked>> | 80% | 39,581 psi | 72% | 2766 fps | 95.8% |
| Winchester StaBALL HD | <<locked>> | 84% | 26,992 psi | 49% | 2552 fps | 96.2% |
| Winchester Supreme 780 | <<locked>> | 92% | 43,033 psi | 78% | 2808 fps | 95% |
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 57 powders for .243 Ackley Improved loaded with the .2425 | 100gr | Prvi Partizan SP. Winchester StaBALL HD delivers the highest muzzle velocity at 3,097 fps; across all powders the maximum-charge window runs from 1,893 fps to 3,097 fps. Alliant Reloder-25 gives the best case fill at 100 %, and 57 of the 57 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 0.2425" calls for a 1:10.5 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 .2425 | 100gr | Prvi Partizan 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.