Load Specifications
Load data in caliber .243 Ackley Improved with .243 | 100gr | Hornady InterLock RN bullet and 60 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Norma MRP, Alliant Reloder-26 and Bofors RP5.
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.
A valid access license is required to use the Personalized Load Calculator.
You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 3100 | <<locked>> | 96% | 48,617 psi | 88% | 2923 fps | 98.9% |
| Accurate 4350 | <<locked>> | 86% | 47,123 psi | 85% | 2917 fps | 99.6% |
| Accurate High Country | <<locked>> | 94% | 49,458 psi | 90% | 3054 fps | 95.9% |
| ADI AR 2208 | <<locked>> | 82% | 49,835 psi | 90% | 2904 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 92% | 48,196 psi | 87% | 2956 fps | 96.5% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 48,211 psi | 87% | 2953 fps | 96.6% |
| Alliant Power Pro Varmint | <<locked>> | 92% | 48,211 psi | 87% | 2953 fps | 96.6% |
| Alliant Reloder-16 | <<locked>> | 88% | 47,935 psi | 87% | 2976 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 84% | 48,559 psi | 88% | 2999 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 92% | 47,630 psi | 86% | 2943 fps | 96.5% |
| Alliant Reloder-22 | <<locked>> | 96% | 48,356 psi | 88% | 3002 fps | 96.9% |
| Alliant Reloder-23 | <<locked>> | 98% | 48,849 psi | 88% | 2999 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 45,469 psi | 82% | 2976 fps | 99.2% |
| Alliant Reloder-26 | <<locked>> | 94% | 48,240 psi | 87% | 3068 fps | 99.8% |
| Bofors RP15 | <<locked>> | 98% | 47,326 psi | 86% | 2979 fps | 96.4% |
| Bofors RP5 | <<locked>> | 96% | 48,356 psi | 88% | 3002 fps | 96.9% |
| Bofors RP7 | <<locked>> | 84% | 47,703 psi | 86% | 2864 fps | 97.4% |
| Hodgdon H414 | <<locked>> | 86% | 49,197 psi | 89% | 2969 fps | 98.3% |
| Hodgdon H4350 | <<locked>> | 84% | 48,849 psi | 88% | 2923 fps | 97.1% |
| Hodgdon Hybrid 100V | <<locked>> | 90% | 48,312 psi | 87% | 2910 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 44,440 psi | 80% | 3002 fps | 96.3% |
| Hodgdon Superformance | <<locked>> | 86% | 48,776 psi | 88% | 2995 fps | 98% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,390 psi | 66% | 1896 fps | 100% |
| IMR 4350 | <<locked>> | 88% | 48,646 psi | 88% | 2904 fps | 97.7% |
| IMR 4451 Enduron | <<locked>> | 84% | 49,298 psi | 89% | 2897 fps | 98.2% |
| IMR 4831 | <<locked>> | 88% | 47,834 psi | 87% | 2917 fps | 99.7% |
| Lovex S065 | <<locked>> | 86% | 49,588 psi | 90% | 2900 fps | 99.2% |
| Lovex S070 | <<locked>> | 86% | 47,485 psi | 86% | 2881 fps | 98.1% |
| Lovex S071ᴾ | <<locked>> | 100% | 46,311 psi | 84% | 2881 fps | 98.5% |
| Norma 204 | <<locked>> | 88% | 49,023 psi | 89% | 2946 fps | 96.6% |
| Norma MRP | <<locked>> | 94% | 47,688 psi | 86% | 3022 fps | 98% |
| Norma URP | <<locked>> | 88% | 49,400 psi | 89% | 2963 fps | 99.8% |
| Ramshot Hunter | <<locked>> | 88% | 48,312 psi | 87% | 2959 fps | 98.8% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 48,515 psi | 88% | 2982 fps | 97.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,014 psi | 67% | 1939 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 82% | 48,167 psi | 87% | 2995 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 46,876 psi | 85% | 2936 fps | 99.4% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 48,747 psi | 88% | 3018 fps | 99.6% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 44,614 psi | 81% | 2999 fps | 97.6% |
| Rottweil R 903 | <<locked>> | 82% | 48,298 psi | 87% | 2887 fps | 100% |
| Rottweil R 905 | <<locked>> | 94% | 49,908 psi | 90% | 2986 fps | 97.2% |
| Rottweil R 907 | <<locked>> | 84% | 47,703 psi | 86% | 2864 fps | 97.4% |
| Shooters World Long Rifle | <<locked>> | 86% | 49,588 psi | 90% | 2900 fps | 99.2% |
| Shooters World SW4350 | <<locked>> | 86% | 47,485 psi | 86% | 2881 fps | 98.1% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 49,443 psi | 89% | 2943 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 82% | 49,182 psi | 89% | 2782 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 48,965 psi | 89% | 2848 fps | 98.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 49,472 psi | 90% | 2979 fps | 97.1% |
| Somchem S355 | <<locked>> | 82% | 48,269 psi | 87% | 2884 fps | 100% |
| Somchem S365 | <<locked>> | 90% | 48,631 psi | 88% | 2969 fps | 100% |
| Somchem S385 | <<locked>> | 92% | 47,485 psi | 86% | 2907 fps | 97.4% |
| Vihtavuori N150 | <<locked>> | 84% | 49,255 psi | 89% | 2861 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 48,080 psi | 87% | 2904 fps | 99.6% |
| Vihtavuori N165 | <<locked>> | 96% | 46,949 psi | 85% | 2881 fps | 96.9% |
| Vihtavuori N550 | <<locked>> | 86% | 47,355 psi | 86% | 2904 fps | 99.5% |
| Vihtavuori N555 | <<locked>> | 94% | 48,080 psi | 87% | 2969 fps | 99.9% |
| Winchester 6.5 StaBALL | <<locked>> | 86% | 47,355 psi | 86% | 2867 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 49,197 psi | 89% | 2969 fps | 98.3% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 47,297 psi | 86% | 3117 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 94% | 47,007 psi | 85% | 2890 fps | 96.3% |
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>> | 86% | 34,534 psi | 62% | 2628 fps | 95.2% |
| Accurate 4350 | <<locked>> | 80% | 38,116 psi | 69% | 2733 fps | 98.1% |
| Accurate High Country | <<locked>> | 92% | 46,137 psi | 83% | 2989 fps | 95% |
| ADI AR 2208 | <<locked>> | 80% | 47,007 psi | 85% | 2851 fps | 99.8% |
| ADI AR 2209 | <<locked>> | 90% | 45,063 psi | 82% | 2894 fps | 95.7% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 45,107 psi | 82% | 2890 fps | 95.7% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 45,107 psi | 82% | 2890 fps | 95.7% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,057 psi | 67% | 2743 fps | 98.2% |
| Alliant Reloder-17 | <<locked>> | 80% | 42,032 psi | 76% | 2874 fps | 99.9% |
| Alliant Reloder-19 | <<locked>> | 90% | 44,585 psi | 81% | 2881 fps | 95.6% |
| Alliant Reloder-22 | <<locked>> | 92% | 42,206 psi | 76% | 2874 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,296 psi | 49% | 2484 fps | 95.7% |
| Alliant Reloder-25 | <<locked>> | 92% | 35,201 psi | 64% | 2730 fps | 96.1% |
| Alliant Reloder-26 | 43.2 gr | 82% | 31,212 psi | 56% | 2657 fps | 95.1% |
| Bofors RP15 | <<locked>> | 96% | 44,527 psi | 81% | 2923 fps | 95.6% |
| Bofors RP5 | 45.6 gr | 92% | 42,206 psi | 76% | 2874 fps | 95% |
| Bofors RP7 | <<locked>> | 80% | 42,090 psi | 76% | 2749 fps | 96% |
| Hodgdon H414 | <<locked>> | 80% | 40,234 psi | 73% | 2782 fps | 96.1% |
| Hodgdon H4350 | <<locked>> | 80% | 43,120 psi | 78% | 2805 fps | 95.5% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 34,534 psi | 62% | 2631 fps | 98.7% |
| Hodgdon Retumbo | <<locked>> | 98% | 41,582 psi | 75% | 2933 fps | 95.2% |
| Hodgdon Superformance | <<locked>> | 80% | 39,131 psi | 71% | 2789 fps | 95.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,195 psi | 49% | 1696 fps | 100% |
| IMR 4350 | <<locked>> | 82% | 40,263 psi | 73% | 2730 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 80% | 43,613 psi | 79% | 2785 fps | 96.9% |
| IMR 4831 | <<locked>> | 80% | 36,753 psi | 67% | 2687 fps | 97.8% |
| Lovex S065 | <<locked>> | 80% | 41,104 psi | 74% | 2733 fps | 97.6% |
| Lovex S070 | <<locked>> | 80% | 39,291 psi | 71% | 2710 fps | 96% |
| Lovex S071 | <<locked>> | 92% | 35,781 psi | 65% | 2657 fps | 95.7% |
| Norma 204 | <<locked>> | 86% | 45,542 psi | 82% | 2881 fps | 95.7% |
| Norma MRP | 45 gr | 88% | 38,624 psi | 70% | 2822 fps | 95.4% |
| Norma URP | <<locked>> | 80% | 37,913 psi | 69% | 2726 fps | 97.9% |
| Ramshot Hunter | <<locked>> | 80% | 36,753 psi | 67% | 2710 fps | 95.9% |
| Ramshot Magnum | <<locked>> | 96% | 41,771 psi | 76% | 2848 fps | 95.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,818 psi | 50% | 1739 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 44,643 psi | 81% | 2930 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 37,927 psi | 69% | 2749 fps | 97.7% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 36,825 psi | 67% | 2756 fps | 97.1% |
| ReloadSwiss RS 76 | <<locked>> | 96% | 38,725 psi | 70% | 2851 fps | 95.3% |
| Rottweil R 903 | <<locked>> | 80% | 45,150 psi | 82% | 2831 fps | 100% |
| Rottweil R 905 | <<locked>> | 90% | 43,816 psi | 79% | 2867 fps | 95.6% |
| Rottweil R 907 | <<locked>> | 80% | 42,090 psi | 76% | 2749 fps | 96% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,104 psi | 74% | 2733 fps | 97.6% |
| Shooters World SW4350 | <<locked>> | 80% | 39,291 psi | 71% | 2710 fps | 96% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 46,267 psi | 84% | 2887 fps | 99.9% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 46,296 psi | 84% | 2736 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,132 psi | 73% | 2671 fps | 96.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 90% | 43,410 psi | 79% | 2858 fps | 95.4% |
| Somchem S355 | <<locked>> | 80% | 45,484 psi | 82% | 2831 fps | 100% |
| Somchem S365 | <<locked>> | 80% | 34,345 psi | 62% | 2680 fps | 99.5% |
| Somchem S385 | <<locked>> | 86% | 38,928 psi | 70% | 2726 fps | 95% |
| Vihtavuori N150 | <<locked>> | 80% | 43,337 psi | 78% | 2756 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 39,247 psi | 71% | 2726 fps | 98.2% |
| Vihtavuori N165 | <<locked>> | 92% | 40,988 psi | 74% | 2762 fps | 95.2% |
| Vihtavuori N550 | <<locked>> | 80% | 38,841 psi | 70% | 2726 fps | 97.9% |
| Vihtavuori N555 | <<locked>> | 80% | 30,168 psi | 55% | 2566 fps | 95.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 38,421 psi | 70% | 2694 fps | 99.6% |
| Winchester 760 | <<locked>> | 80% | 40,234 psi | 73% | 2782 fps | 96.1% |
| Winchester StaBALL HD | <<locked>> | 82% | 25,715 psi | 47% | 2507 fps | 95.3% |
| Winchester Supreme 780 | <<locked>> | 92% | 43,845 psi | 79% | 2828 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 60 powders for .243 Ackley Improved loaded with the .243 | 100gr | Hornady InterLock RN. Winchester StaBALL HD delivers the highest muzzle velocity at 3,117 fps; across all powders the maximum-charge window runs from 1,896 fps to 3,117 fps. Alliant Reloder-25 gives the best case fill at 100 %, and 60 of the 60 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 1:12.0 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. Norma MRP, Alliant Reloder-26, Bofors RP5 rank at the top here: for .243 Ackley Improved with the .243 | 100gr | Hornady InterLock RN 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.