Load Specifications
Load data in caliber .243 Ackley Improved with .243 | 85gr | Sierra VarmintKing 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, Alliant Reloder-16 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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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 3100ᴾ | <<locked>> | 100% | 48,646 psi | 88% | 3123 fps | 97.6% |
| Accurate 4064 | <<locked>> | 82% | 47,471 psi | 86% | 3064 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 47,195 psi | 85% | 3130 fps | 98.6% |
| ADI AR 2208 | <<locked>> | 84% | 48,080 psi | 87% | 3081 fps | 99.1% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 49,647 psi | 90% | 3251 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 48,515 psi | 88% | 3110 fps | 99.9% |
| Alliant Reloder-15 | <<locked>> | 82% | 48,762 psi | 88% | 3130 fps | 99.3% |
| Alliant Reloder-16 | <<locked>> | 92% | 48,457 psi | 88% | 3199 fps | 99.2% |
| Alliant Reloder-17 | <<locked>> | 88% | 49,313 psi | 89% | 3235 fps | 99.9% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 45,585 psi | 82% | 3153 fps | 99.7% |
| Alliant Reloder-26 | <<locked>> | 98% | 48,385 psi | 88% | 3274 fps | 98.9% |
| Bofors RP3 | <<locked>> | 84% | 48,849 psi | 88% | 3123 fps | 99.9% |
| Bofors RP7 | <<locked>> | 88% | 48,820 psi | 88% | 3087 fps | 96% |
| Hodgdon H380 | <<locked>> | 84% | 49,617 psi | 90% | 3133 fps | 98.6% |
| Hodgdon H414 | <<locked>> | 90% | 49,777 psi | 90% | 3189 fps | 96.9% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 48,573 psi | 88% | 3130 fps | 99.8% |
| Hodgdon Superformance | <<locked>> | 90% | 49,806 psi | 90% | 3212 fps | 96.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,998 psi | 65% | 2047 fps | 100% |
| IMR 4064 | <<locked>> | 82% | 47,645 psi | 86% | 3064 fps | 99.2% |
| IMR 4350 | <<locked>> | 92% | 49,661 psi | 90% | 3120 fps | 96.2% |
| IMR 4451 Enduron | <<locked>> | 86% | 47,442 psi | 86% | 3061 fps | 96.1% |
| IMR 4831 | <<locked>> | 92% | 48,051 psi | 87% | 3130 fps | 98.9% |
| Lovex S062 | <<locked>> | 82% | 47,819 psi | 87% | 3068 fps | 99.9% |
| Lovex S065 | <<locked>> | 88% | 47,442 psi | 86% | 3064 fps | 97.6% |
| Lovex S070 | <<locked>> | 90% | 48,182 psi | 87% | 3097 fps | 96.7% |
| Norma 203B | <<locked>> | 82% | 48,109 psi | 87% | 3114 fps | 99.5% |
| Norma MRP | <<locked>> | 98% | 47,935 psi | 87% | 3225 fps | 96.3% |
| Norma URP | <<locked>> | 92% | 49,777 psi | 90% | 3182 fps | 99% |
| Ramshot Big Game | <<locked>> | 82% | 48,240 psi | 87% | 3130 fps | 99.4% |
| Ramshot Hunter | <<locked>> | 92% | 48,689 psi | 88% | 3173 fps | 97.5% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,506 psi | 66% | 2093 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 49,530 psi | 90% | 3107 fps | 97.3% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 48,718 psi | 88% | 3232 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 46,920 psi | 85% | 3146 fps | 98.4% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 49,588 psi | 90% | 3238 fps | 98.7% |
| Rottweil R 902 | <<locked>> | 82% | 49,545 psi | 90% | 3081 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 49,023 psi | 89% | 3117 fps | 99.8% |
| Rottweil R 907 | <<locked>> | 88% | 48,820 psi | 88% | 3087 fps | 96% |
| Shooters World Long Rifle | <<locked>> | 88% | 47,442 psi | 86% | 3064 fps | 97.6% |
| Shooters World Precision | <<locked>> | 82% | 47,819 psi | 87% | 3068 fps | 99.9% |
| Shooters World SW4350 | <<locked>> | 90% | 48,182 psi | 87% | 3097 fps | 96.7% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 47,123 psi | 85% | 3114 fps | 99.4% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 47,572 psi | 86% | 2972 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 46,905 psi | 85% | 3002 fps | 96.2% |
| Somchem S355 | <<locked>> | 86% | 49,182 psi | 89% | 3117 fps | 99.8% |
| Somchem S365 | <<locked>> | 94% | 48,254 psi | 87% | 3186 fps | 100% |
| Vihtavuori N135 | <<locked>> | 82% | 49,661 psi | 90% | 3058 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 49,908 psi | 90% | 3061 fps | 100% |
| Vihtavuori N150 | <<locked>> | 86% | 47,282 psi | 86% | 3038 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 48,544 psi | 88% | 3120 fps | 98.8% |
| Vihtavuori N540 | <<locked>> | 82% | 48,225 psi | 87% | 3048 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 47,950 psi | 87% | 3123 fps | 98.5% |
| Vihtavuori N555 | <<locked>> | 98% | 47,529 psi | 86% | 3176 fps | 99.2% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 48,341 psi | 87% | 3091 fps | 99.9% |
| Winchester 760 | <<locked>> | 90% | 49,777 psi | 90% | 3189 fps | 96.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 41,162 psi | 74% | 3179 fps | 99.9% |
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>> | 94% | 39,363 psi | 71% | 2930 fps | 95% |
| Accurate 4064 | <<locked>> | 80% | 44,411 psi | 80% | 3005 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 35,795 psi | 65% | 2871 fps | 95.6% |
| ADI AR 2208 | <<locked>> | 80% | 42,424 psi | 77% | 2963 fps | 98.1% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 46,383 psi | 84% | 3182 fps | 98.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 42,496 psi | 77% | 2989 fps | 99.3% |
| Alliant Reloder-15 | <<locked>> | 80% | 45,672 psi | 83% | 3068 fps | 98.9% |
| Alliant Reloder-16 | 39.5 gr | 82% | 35,186 psi | 64% | 2881 fps | 95.5% |
| Alliant Reloder-17 | <<locked>> | 80% | 37,144 psi | 67% | 2959 fps | 98% |
| Alliant Reloder-23 | <<locked>> | 88% | 31,038 psi | 56% | 2776 fps | 95.4% |
| Alliant Reloder-26 | 47.9 gr | 90% | 36,245 psi | 66% | 2979 fps | 95.1% |
| Bofors RP3 | <<locked>> | 80% | 42,627 psi | 77% | 2999 fps | 99.3% |
| Bofors RP7 | <<locked>> | 86% | 46,050 psi | 83% | 3028 fps | 95.2% |
| Hodgdon H380 | <<locked>> | 80% | 43,134 psi | 78% | 2999 fps | 97.3% |
| Hodgdon H414 | <<locked>> | 86% | 43,308 psi | 78% | 3051 fps | 95.1% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 30,530 psi | 55% | 2707 fps | 95.4% |
| Hodgdon Superformance | <<locked>> | 88% | 46,325 psi | 84% | 3140 fps | 95.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,672 psi | 48% | 1827 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 44,585 psi | 81% | 3005 fps | 98.7% |
| IMR 4350 | <<locked>> | 90% | 46,586 psi | 84% | 3058 fps | 95.4% |
| IMR 4451 Enduron | <<locked>> | 84% | 44,773 psi | 81% | 3005 fps | 95.3% |
| IMR 4831 | <<locked>> | 82% | 34,432 psi | 62% | 2818 fps | 95.1% |
| Lovex S062 | <<locked>> | 80% | 44,773 psi | 81% | 3009 fps | 99.7% |
| Lovex S065 | <<locked>> | 82% | 39,334 psi | 71% | 2884 fps | 95.3% |
| Lovex S070 | <<locked>> | 86% | 42,569 psi | 77% | 2976 fps | 95.1% |
| Norma 203B | <<locked>> | 80% | 45,049 psi | 82% | 3051 fps | 99.1% |
| Norma MRP | <<locked>> | 96% | 44,788 psi | 81% | 3159 fps | 95.4% |
| Norma URP | <<locked>> | 82% | 35,650 psi | 65% | 2867 fps | 95.4% |
| Ramshot Big Game | <<locked>> | 80% | 45,165 psi | 82% | 3068 fps | 99% |
| Ramshot Hunter | <<locked>> | 88% | 42,380 psi | 77% | 3035 fps | 95.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,195 psi | 49% | 1877 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 43,540 psi | 79% | 2986 fps | 95.8% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 39,479 psi | 71% | 3035 fps | 99.9% |
| ReloadSwiss RS 62 | <<locked>> | 82% | 35,433 psi | 64% | 2884 fps | 95% |
| ReloadSwiss RS 70 | 44.3 gr | 84% | 37,565 psi | 68% | 2956 fps | 95.1% |
| Rottweil R 902 | <<locked>> | 80% | 46,702 psi | 85% | 3028 fps | 99.8% |
| Rottweil R 903 | <<locked>> | 80% | 39,987 psi | 72% | 2933 fps | 98.7% |
| Rottweil R 907 | <<locked>> | 86% | 46,050 psi | 83% | 3028 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 82% | 39,334 psi | 71% | 2884 fps | 95.3% |
| Shooters World Precision | <<locked>> | 80% | 44,773 psi | 81% | 3009 fps | 99.7% |
| Shooters World SW4350 | <<locked>> | 86% | 42,569 psi | 77% | 2976 fps | 95.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 41,249 psi | 75% | 2992 fps | 98.4% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 41,858 psi | 76% | 2867 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 43,888 psi | 79% | 2940 fps | 95.3% |
| Somchem S355 | <<locked>> | 80% | 40,640 psi | 74% | 2940 fps | 98.7% |
| Somchem S365 | <<locked>> | 80% | 30,052 psi | 54% | 2749 fps | 96.8% |
| Vihtavuori N135 | <<locked>> | 80% | 46,340 psi | 84% | 2999 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 46,746 psi | 85% | 3009 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 38,638 psi | 70% | 2861 fps | 99.2% |
| Vihtavuori N160 | <<locked>> | 80% | 34,809 psi | 63% | 2808 fps | 95% |
| Vihtavuori N540 | <<locked>> | 80% | 45,208 psi | 82% | 2995 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 36,622 psi | 66% | 2867 fps | 95.5% |
| Vihtavuori N555 | <<locked>> | 88% | 34,040 psi | 62% | 2864 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 34,374 psi | 62% | 2782 fps | 97.4% |
| Winchester 760 | <<locked>> | 86% | 43,584 psi | 79% | 3058 fps | 95.2% |
| Winchester StaBALL HD | <<locked>> | 90% | 29,428 psi | 53% | 2799 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 56 powders for .243 Ackley Improved loaded with the .243 | 85gr | Sierra VarmintKing. Alliant Reloder-26 delivers the highest muzzle velocity at 3,274 fps; across all powders the maximum-charge window runs from 2,047 fps to 3,274 fps. Accurate 3100 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 65–90 %, leaving at least 10 % headroom. The 85.0 gr projectile in 0.243" calls for a 1:11.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Reloder-23, 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, Alliant Reloder-16, ReloadSwiss RS 70 rank at the top here: for .243 Ackley Improved with the .243 | 85gr | Sierra VarmintKing 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.