Load Specifications
Load data in caliber .243 Ackley Improved with .243 | 100gr | Norma SSP 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, 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% | 47,601 psi | 86% | 2904 fps | 98.7% |
| Accurate 4350 | <<locked>> | 88% | 49,371 psi | 89% | 2956 fps | 99.8% |
| ADI AR 2208 | <<locked>> | 82% | 49,400 psi | 89% | 2890 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 92% | 47,268 psi | 86% | 2933 fps | 96.1% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 47,616 psi | 86% | 2936 fps | 96.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 49,980 psi | 90% | 2917 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 88% | 47,195 psi | 85% | 2963 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 84% | 47,819 psi | 87% | 2982 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 49,937 psi | 90% | 2982 fps | 97% |
| Alliant Reloder-22 | <<locked>> | 96% | 47,384 psi | 86% | 2979 fps | 96.5% |
| Alliant Reloder-23 | <<locked>> | 98% | 47,863 psi | 87% | 2982 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 44,657 psi | 81% | 2956 fps | 98.9% |
| Alliant Reloder-26 | <<locked>> | 94% | 47,282 psi | 86% | 3045 fps | 99.7% |
| Bofors RP15ᴾ | <<locked>> | 100% | 49,690 psi | 90% | 3022 fps | 96.9% |
| Bofors RP5 | <<locked>> | 96% | 47,384 psi | 86% | 2979 fps | 96.5% |
| Bofors RP7 | <<locked>> | 84% | 47,021 psi | 85% | 2848 fps | 97.2% |
| Hodgdon H414 | <<locked>> | 86% | 48,457 psi | 88% | 2949 fps | 98.1% |
| Hodgdon H4350 | <<locked>> | 84% | 48,138 psi | 87% | 2904 fps | 96.8% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 47,572 psi | 86% | 2894 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 47,848 psi | 87% | 2976 fps | 97.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,448 psi | 66% | 1893 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 48,008 psi | 87% | 2887 fps | 97.5% |
| IMR 4451 Enduron | <<locked>> | 84% | 48,617 psi | 88% | 2881 fps | 98% |
| IMR 4831 | <<locked>> | 88% | 47,123 psi | 85% | 2900 fps | 99.6% |
| Lovex S065 | <<locked>> | 86% | 48,936 psi | 89% | 2884 fps | 99% |
| Lovex S070 | <<locked>> | 88% | 49,966 psi | 90% | 2923 fps | 98.5% |
| Lovex S071ᴾ | <<locked>> | 100% | 45,324 psi | 82% | 2861 fps | 98.3% |
| Norma 204 | <<locked>> | 88% | 48,051 psi | 87% | 2927 fps | 96.2% |
| Norma MRP | <<locked>> | 94% | 46,789 psi | 85% | 3002 fps | 97.8% |
| Norma URP | <<locked>> | 88% | 48,675 psi | 88% | 2946 fps | 99.7% |
| Ramshot Hunter | <<locked>> | 88% | 47,326 psi | 86% | 2936 fps | 98.6% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 47,427 psi | 86% | 2959 fps | 97.2% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,072 psi | 67% | 1936 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 47,384 psi | 86% | 2979 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 49,414 psi | 89% | 2979 fps | 99.7% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 47,819 psi | 87% | 2999 fps | 99.5% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 43,627 psi | 79% | 2969 fps | 97.1% |
| Rottweil R 903 | <<locked>> | 82% | 47,485 psi | 86% | 2871 fps | 100% |
| Rottweil R 905 | <<locked>> | 94% | 49,240 psi | 89% | 2969 fps | 96.9% |
| Rottweil R 907 | <<locked>> | 84% | 47,021 psi | 85% | 2848 fps | 97.2% |
| Shooters World Long Rifle | <<locked>> | 86% | 48,936 psi | 89% | 2884 fps | 99% |
| Shooters World SW4350 | <<locked>> | 88% | 49,966 psi | 90% | 2923 fps | 98.5% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 48,675 psi | 88% | 2927 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 48,747 psi | 88% | 2772 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 48,327 psi | 87% | 2831 fps | 98% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 48,805 psi | 88% | 2966 fps | 96.8% |
| Somchem S355 | <<locked>> | 82% | 47,776 psi | 86% | 2871 fps | 100% |
| Somchem S365 | <<locked>> | 90% | 47,819 psi | 87% | 2953 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 49,821 psi | 90% | 2946 fps | 97.8% |
| Vihtavuori N150 | <<locked>> | 84% | 48,805 psi | 88% | 2848 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 47,326 psi | 86% | 2887 fps | 99.5% |
| Vihtavuori N165 | <<locked>> | 98% | 49,298 psi | 89% | 2923 fps | 97.4% |
| Vihtavuori N550 | <<locked>> | 88% | 49,835 psi | 90% | 2946 fps | 99.7% |
| Vihtavuori N555 | <<locked>> | 94% | 46,992 psi | 85% | 2949 fps | 99.8% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 49,980 psi | 90% | 2910 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 48,457 psi | 88% | 2949 fps | 98.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 46,398 psi | 84% | 3097 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 49,879 psi | 90% | 2940 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% | 36,158 psi | 65% | 2664 fps | 95.7% |
| Accurate 4350 | <<locked>> | 80% | 37,594 psi | 68% | 2720 fps | 97.9% |
| ADI AR 2208 | <<locked>> | 80% | 46,238 psi | 84% | 2835 fps | 99.7% |
| ADI AR 2209 | <<locked>> | 90% | 44,469 psi | 80% | 2874 fps | 95.3% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 44,483 psi | 80% | 2871 fps | 95.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 46,775 psi | 85% | 2858 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,651 psi | 66% | 2730 fps | 98% |
| Alliant Reloder-17 | <<locked>> | 80% | 41,582 psi | 75% | 2861 fps | 99.8% |
| Alliant Reloder-19 | <<locked>> | 90% | 43,961 psi | 80% | 2864 fps | 95.3% |
| Alliant Reloder-22 | <<locked>> | 94% | 44,251 psi | 80% | 2917 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 80% | 26,789 psi | 48% | 2461 fps | 95.3% |
| Alliant Reloder-25 | <<locked>> | 92% | 34,476 psi | 62% | 2703 fps | 95.6% |
| Alliant Reloder-26 | 43.6 gr | 84% | 32,851 psi | 59% | 2703 fps | 95.8% |
| Bofors RP15 | <<locked>> | 96% | 43,642 psi | 79% | 2900 fps | 95.3% |
| Bofors RP5 | <<locked>> | 94% | 44,251 psi | 80% | 2917 fps | 95.6% |
| Bofors RP7 | <<locked>> | 80% | 41,684 psi | 75% | 2740 fps | 95.8% |
| Hodgdon H414 | <<locked>> | 80% | 39,537 psi | 72% | 2766 fps | 95.8% |
| Hodgdon H4350 | <<locked>> | 80% | 42,409 psi | 77% | 2789 fps | 95.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 34,069 psi | 62% | 2615 fps | 98.5% |
| Hodgdon Superformance | <<locked>> | 82% | 41,205 psi | 75% | 2835 fps | 95.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,122 psi | 49% | 1690 fps | 100% |
| IMR 4350 | <<locked>> | 82% | 39,624 psi | 72% | 2713 fps | 95.2% |
| IMR 4451 Enduron | <<locked>> | 80% | 42,946 psi | 78% | 2766 fps | 96.7% |
| IMR 4831 | <<locked>> | 80% | 36,042 psi | 65% | 2667 fps | 97.5% |
| Lovex S065 | <<locked>> | 80% | 40,422 psi | 73% | 2713 fps | 97.4% |
| Lovex S070 | <<locked>> | 80% | 38,609 psi | 70% | 2690 fps | 95.7% |
| Lovex S071 | <<locked>> | 92% | 34,882 psi | 63% | 2631 fps | 95.3% |
| Norma 204 | <<locked>> | 86% | 44,875 psi | 81% | 2861 fps | 95.4% |
| Norma MRP | 44.4 gr | 88% | 38,043 psi | 69% | 2805 fps | 95% |
| Norma URP | <<locked>> | 80% | 37,188 psi | 67% | 2707 fps | 97.7% |
| Ramshot Hunter | <<locked>> | 80% | 36,129 psi | 65% | 2690 fps | 95.5% |
| Ramshot Magnum | <<locked>> | 96% | 41,060 psi | 74% | 2828 fps | 95.3% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,746 psi | 50% | 1732 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 44,150 psi | 80% | 2920 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 37,260 psi | 67% | 2730 fps | 97.5% |
| ReloadSwiss RS 70 | 41.2 gr | 80% | 36,230 psi | 66% | 2736 fps | 96.7% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 40,727 psi | 74% | 2900 fps | 96% |
| Rottweil R 903 | <<locked>> | 80% | 44,338 psi | 80% | 2812 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 90% | 43,134 psi | 78% | 2848 fps | 95.3% |
| Rottweil R 907 | <<locked>> | 80% | 41,684 psi | 75% | 2740 fps | 95.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,422 psi | 73% | 2713 fps | 97.4% |
| Shooters World SW4350 | <<locked>> | 80% | 38,609 psi | 70% | 2690 fps | 95.7% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 45,542 psi | 82% | 2871 fps | 99.8% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 45,832 psi | 83% | 2723 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 39,523 psi | 72% | 2654 fps | 95.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 42,728 psi | 77% | 2841 fps | 95.1% |
| Somchem S355 | <<locked>> | 80% | 44,686 psi | 81% | 2812 fps | 99.9% |
| Somchem S365 | <<locked>> | 80% | 33,881 psi | 61% | 2667 fps | 99.4% |
| Somchem S385 | <<locked>> | 88% | 41,002 psi | 74% | 2769 fps | 95.6% |
| Vihtavuori N150 | <<locked>> | 80% | 42,598 psi | 77% | 2740 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 38,798 psi | 70% | 2713 fps | 98.1% |
| Vihtavuori N165 | <<locked>> | 94% | 42,960 psi | 78% | 2802 fps | 95.7% |
| Vihtavuori N550 | <<locked>> | 80% | 38,174 psi | 69% | 2710 fps | 97.7% |
| Vihtavuori N555 | <<locked>> | 80% | 29,472 psi | 53% | 2543 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 37,855 psi | 69% | 2677 fps | 99.5% |
| Winchester 760 | <<locked>> | 80% | 39,537 psi | 72% | 2766 fps | 95.8% |
| Winchester StaBALL HD | <<locked>> | 84% | 26,963 psi | 49% | 2552 fps | 96.2% |
| Winchester Supreme 780 | <<locked>> | 92% | 43,294 psi | 78% | 2815 fps | 95.1% |
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 | 100gr | Norma SSP. 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 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 100.0 gr projectile in 0.243" 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 .243 | 100gr | Norma SSP 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.