Load Specifications
Load data in caliber .243 Ackley Improved with .243 | 100gr | Sellier & Bellot SP bullet and 59 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% | 47,224 psi | 85% | 2894 fps | 98.6% |
| Accurate 4350 | <<locked>> | 88% | 49,211 psi | 89% | 2953 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 82% | 48,936 psi | 89% | 2881 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 92% | 46,876 psi | 85% | 2923 fps | 96% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 47,181 psi | 85% | 2927 fps | 96.2% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 47,181 psi | 85% | 2927 fps | 96.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 49,487 psi | 90% | 2907 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 88% | 47,065 psi | 85% | 2956 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 84% | 47,326 psi | 86% | 2972 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 49,559 psi | 90% | 2976 fps | 96.8% |
| Alliant Reloder-22 | <<locked>> | 96% | 47,036 psi | 85% | 2972 fps | 96.4% |
| Alliant Reloder-23 | <<locked>> | 98% | 47,413 psi | 86% | 2972 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 44,324 psi | 80% | 2946 fps | 98.8% |
| Alliant Reloder-26 | <<locked>> | 94% | 46,876 psi | 85% | 3038 fps | 99.6% |
| Bofors RP15ᴾ | <<locked>> | 100% | 49,284 psi | 89% | 3012 fps | 96.8% |
| Bofors RP5 | <<locked>> | 96% | 47,036 psi | 85% | 2972 fps | 96.4% |
| Bofors RP7 | <<locked>> | 86% | 49,763 psi | 90% | 2897 fps | 97.7% |
| Hodgdon H414 | <<locked>> | 86% | 48,022 psi | 87% | 2943 fps | 98% |
| Hodgdon H4350 | <<locked>> | 84% | 48,022 psi | 87% | 2900 fps | 96.7% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 47,079 psi | 85% | 2884 fps | 100% |
| Hodgdon Superformance | <<locked>> | 86% | 47,471 psi | 86% | 2966 fps | 97.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,434 psi | 66% | 1890 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 47,587 psi | 86% | 2874 fps | 97.3% |
| IMR 4451 Enduron | <<locked>> | 84% | 48,501 psi | 88% | 2877 fps | 97.9% |
| IMR 4831 | <<locked>> | 90% | 49,632 psi | 90% | 2943 fps | 99.8% |
| Lovex S065 | <<locked>> | 86% | 48,472 psi | 88% | 2877 fps | 99% |
| Lovex S070 | <<locked>> | 88% | 49,530 psi | 90% | 2913 fps | 98.4% |
| Lovex S071ᴾ | <<locked>> | 100% | 44,904 psi | 81% | 2851 fps | 98.2% |
| Norma 204 | <<locked>> | 88% | 47,659 psi | 86% | 2917 fps | 96.1% |
| Norma MRP | <<locked>> | 96% | 49,719 psi | 90% | 3054 fps | 98.3% |
| Norma URP | <<locked>> | 88% | 48,182 psi | 87% | 2936 fps | 99.6% |
| Ramshot Hunter | <<locked>> | 88% | 46,891 psi | 85% | 2927 fps | 98.5% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 47,065 psi | 85% | 2953 fps | 97.1% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,057 psi | 67% | 1932 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 46,862 psi | 85% | 2969 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 48,965 psi | 89% | 2972 fps | 99.6% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 47,456 psi | 86% | 2989 fps | 99.4% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 43,323 psi | 78% | 2963 fps | 97% |
| Rottweil R 903 | <<locked>> | 82% | 47,326 psi | 86% | 2867 fps | 100% |
| Rottweil R 905 | <<locked>> | 94% | 48,849 psi | 88% | 2963 fps | 96.8% |
| Rottweil R 907 | <<locked>> | 86% | 49,763 psi | 90% | 2897 fps | 97.7% |
| Shooters World Long Rifle | <<locked>> | 86% | 48,472 psi | 88% | 2877 fps | 99% |
| Shooters World SW4350 | <<locked>> | 88% | 49,530 psi | 90% | 2913 fps | 98.4% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 48,544 psi | 88% | 2923 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 48,240 psi | 87% | 2762 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 47,921 psi | 87% | 2822 fps | 97.9% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 48,399 psi | 88% | 2956 fps | 96.7% |
| Somchem S355 | <<locked>> | 82% | 47,340 psi | 86% | 2861 fps | 100% |
| Somchem S365 | <<locked>> | 90% | 47,340 psi | 86% | 2946 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 49,400 psi | 89% | 2936 fps | 97.7% |
| Vihtavuori N150 | <<locked>> | 84% | 48,356 psi | 88% | 2841 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 46,905 psi | 85% | 2877 fps | 99.4% |
| Vihtavuori N165 | <<locked>> | 98% | 48,907 psi | 89% | 2913 fps | 97.2% |
| Vihtavuori N550 | <<locked>> | 88% | 49,414 psi | 89% | 2936 fps | 99.6% |
| Vihtavuori N555 | <<locked>> | 96% | 49,922 psi | 90% | 2999 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 49,574 psi | 90% | 2900 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 48,022 psi | 87% | 2943 fps | 98% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 45,992 psi | 83% | 3087 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 96% | 49,487 psi | 90% | 2930 fps | 96.7% |
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% | 36,013 psi | 65% | 2661 fps | 95.7% |
| Accurate 4350 | <<locked>> | 80% | 37,159 psi | 67% | 2707 fps | 97.7% |
| ADI AR 2208 | <<locked>> | 80% | 46,122 psi | 83% | 2828 fps | 99.7% |
| ADI AR 2209 | <<locked>> | 90% | 44,063 psi | 80% | 2864 fps | 95.2% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 44,092 psi | 80% | 2864 fps | 95.3% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 44,092 psi | 80% | 2864 fps | 95.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 46,601 psi | 84% | 2854 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,230 psi | 66% | 2717 fps | 97.8% |
| Alliant Reloder-17 | <<locked>> | 80% | 41,147 psi | 74% | 2851 fps | 99.8% |
| Alliant Reloder-19 | <<locked>> | 90% | 43,584 psi | 79% | 2854 fps | 95.2% |
| Alliant Reloder-22 | <<locked>> | 94% | 43,874 psi | 79% | 2907 fps | 95.4% |
| Alliant Reloder-23 | <<locked>> | 80% | 26,658 psi | 48% | 2457 fps | 95.2% |
| Alliant Reloder-25 | <<locked>> | 92% | 34,171 psi | 62% | 2694 fps | 95.4% |
| Alliant Reloder-26 | 43.4 gr | 84% | 32,735 psi | 59% | 2700 fps | 95.7% |
| Bofors RP15 | <<locked>> | 96% | 43,265 psi | 78% | 2890 fps | 95.1% |
| Bofors RP5 | <<locked>> | 94% | 43,874 psi | 79% | 2907 fps | 95.4% |
| Bofors RP7 | <<locked>> | 80% | 41,249 psi | 75% | 2726 fps | 95.6% |
| Hodgdon H414 | <<locked>> | 80% | 39,117 psi | 71% | 2753 fps | 95.6% |
| Hodgdon H4350 | <<locked>> | 80% | 42,032 psi | 76% | 2776 fps | 95% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 33,895 psi | 61% | 2612 fps | 98.4% |
| Hodgdon Superformance | <<locked>> | 82% | 41,133 psi | 74% | 2831 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,050 psi | 49% | 1686 fps | 100% |
| IMR 4350 | <<locked>> | 82% | 39,508 psi | 71% | 2707 fps | 95.1% |
| IMR 4451 Enduron | <<locked>> | 80% | 42,815 psi | 77% | 2762 fps | 96.6% |
| IMR 4831 | <<locked>> | 80% | 35,897 psi | 65% | 2661 fps | 97.4% |
| Lovex S065 | <<locked>> | 80% | 40,277 psi | 73% | 2710 fps | 97.3% |
| Lovex S070 | <<locked>> | 80% | 38,479 psi | 70% | 2684 fps | 95.6% |
| Lovex S071 | <<locked>> | 92% | 34,780 psi | 63% | 2628 fps | 95.2% |
| Norma 204 | <<locked>> | 86% | 44,802 psi | 81% | 2858 fps | 95.3% |
| Norma MRP | 45.1 gr | 90% | 40,379 psi | 73% | 2861 fps | 95.9% |
| Norma URP | <<locked>> | 80% | 37,028 psi | 67% | 2703 fps | 97.6% |
| Ramshot Hunter | <<locked>> | 80% | 35,984 psi | 65% | 2687 fps | 95.4% |
| Ramshot Magnum | <<locked>> | 96% | 40,756 psi | 74% | 2818 fps | 95.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,673 psi | 50% | 1729 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 43,700 psi | 79% | 2910 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 37,072 psi | 67% | 2726 fps | 97.4% |
| ReloadSwiss RS 70 | 40.9 gr | 80% | 35,882 psi | 65% | 2723 fps | 96.6% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 40,480 psi | 73% | 2894 fps | 95.9% |
| Rottweil R 903 | <<locked>> | 80% | 44,164 psi | 80% | 2808 fps | 99.9% |
| Rottweil R 905 | <<locked>> | 90% | 42,728 psi | 77% | 2838 fps | 95.1% |
| Rottweil R 907 | <<locked>> | 80% | 41,249 psi | 75% | 2726 fps | 95.6% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,277 psi | 73% | 2710 fps | 97.3% |
| Shooters World SW4350 | <<locked>> | 80% | 38,479 psi | 70% | 2684 fps | 95.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 45,382 psi | 82% | 2864 fps | 99.8% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 45,368 psi | 82% | 2717 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 39,392 psi | 71% | 2651 fps | 95.8% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 45,397 psi | 82% | 2897 fps | 95.9% |
| Somchem S355 | <<locked>> | 80% | 44,541 psi | 81% | 2808 fps | 99.9% |
| Somchem S365 | <<locked>> | 80% | 33,460 psi | 61% | 2657 fps | 99.3% |
| Somchem S385 | <<locked>> | 88% | 40,582 psi | 73% | 2759 fps | 95.4% |
| Vihtavuori N150 | <<locked>> | 80% | 42,496 psi | 77% | 2736 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 38,363 psi | 69% | 2703 fps | 97.9% |
| Vihtavuori N165 | <<locked>> | 94% | 42,583 psi | 77% | 2792 fps | 95.6% |
| Vihtavuori N550 | <<locked>> | 80% | 38,029 psi | 69% | 2707 fps | 97.6% |
| Vihtavuori N555 | <<locked>> | 80% | 29,312 psi | 53% | 2539 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 37,521 psi | 68% | 2671 fps | 99.4% |
| Winchester 760 | <<locked>> | 80% | 39,392 psi | 71% | 2762 fps | 95.7% |
| Winchester StaBALL HD | <<locked>> | 84% | 26,890 psi | 49% | 2549 fps | 96.1% |
| Winchester Supreme 780 | <<locked>> | 94% | 46,064 psi | 83% | 2867 fps | 95.8% |
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 59 powders for .243 Ackley Improved loaded with the .243 | 100gr | Sellier & Bellot SP. Winchester StaBALL HD delivers the highest muzzle velocity at 3,087 fps; across all powders the maximum-charge window runs from 1,890 fps to 3,087 fps. Alliant Reloder-25 gives the best case fill at 100 %, and 59 of the 59 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 | Sellier & Bellot 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.