Load Specifications
Load data in caliber .243 WSSM with .243 | 90gr | Barnes X S bullet and 97 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 60, ReloadSwiss RS 70 and Alliant Reloder-16.
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 2495 | <<locked>> | 84% | 55,999 psi | 88% | 3035 fps | 100% |
| Accurate 2700 | <<locked>> | 86% | 56,144 psi | 88% | 3061 fps | 97.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 49,371 psi | 77% | 3035 fps | 97.7% |
| Accurate 4064 | <<locked>> | 86% | 55,985 psi | 88% | 3084 fps | 100% |
| Accurate 4350 | <<locked>> | 94% | 55,100 psi | 86% | 3166 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 84% | 57,479 psi | 90% | 3150 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 54,781 psi | 86% | 3091 fps | 99.8% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 55,840 psi | 88% | 3186 fps | 96.3% |
| ADI Benchmark 8208 | <<locked>> | 82% | 56,101 psi | 88% | 3094 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 57,101 psi | 89% | 3274 fps | 99.9% |
| Alliant Power Pro Varmint | <<locked>> | 82% | 54,839 psi | 86% | 3107 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 88% | 55,796 psi | 87% | 3127 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 56,057 psi | 88% | 3143 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 96% | 55,187 psi | 86% | 3215 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 92% | 56,347 psi | 88% | 3248 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 54,723 psi | 86% | 3169 fps | 96.3% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 45,963 psi | 72% | 3058 fps | 99.7% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 40,872 psi | 64% | 2953 fps | 96.1% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 52,214 psi | 82% | 3248 fps | 99.4% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 57,276 psi | 90% | 3163 fps | 99.8% |
| Bofors RP3 | <<locked>> | 88% | 56,753 psi | 89% | 3143 fps | 100% |
| Bofors RP7 | <<locked>> | 92% | 55,970 psi | 88% | 3104 fps | 97.4% |
| Hodgdon Benchmark | <<locked>> | 82% | 57,319 psi | 90% | 3068 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 82% | 56,130 psi | 88% | 3127 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 57,319 psi | 90% | 3156 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 94% | 56,913 psi | 89% | 3209 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 92% | 57,116 psi | 90% | 3166 fps | 97% |
| Hodgdon H4895 | <<locked>> | 82% | 54,679 psi | 86% | 3104 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 55,521 psi | 87% | 3140 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 84% | 54,302 psi | 85% | 3140 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 57,188 psi | 90% | 3241 fps | 98% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,172 psi | 57% | 1952 fps | 100% |
| Hodgdon VARGET | <<locked>> | 84% | 55,506 psi | 87% | 3104 fps | 100% |
| IMR 3031 | <<locked>> | 82% | 54,824 psi | 86% | 3087 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 57,740 psi | 90% | 3130 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 57,421 psi | 90% | 3107 fps | 98.1% |
| IMR 4350 | <<locked>> | 96% | 56,434 psi | 88% | 3133 fps | 97.6% |
| IMR 4451 Enduron | <<locked>> | 92% | 57,334 psi | 90% | 3133 fps | 98.1% |
| IMR 4831 | <<locked>> | 96% | 55,172 psi | 86% | 3150 fps | 99.7% |
| IMR 4895 | <<locked>> | 86% | 57,421 psi | 90% | 3176 fps | 100% |
| IMR 8208 XBR | <<locked>> | 82% | 56,101 psi | 88% | 3094 fps | 100% |
| Lovex D073.6 | <<locked>> | 82% | 54,578 psi | 86% | 3074 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 56,420 psi | 88% | 3068 fps | 100% |
| Lovex S062 | <<locked>> | 86% | 54,868 psi | 86% | 3077 fps | 100% |
| Lovex S065 | <<locked>> | 92% | 54,389 psi | 85% | 3081 fps | 98.7% |
| Lovex S070 | <<locked>> | 94% | 55,651 psi | 87% | 3123 fps | 98.1% |
| Lovex S071ᴾ | <<locked>> | 100% | 41,626 psi | 65% | 2881 fps | 95.8% |
| Norma 201 | <<locked>> | 84% | 56,768 psi | 89% | 3097 fps | 100% |
| Norma 202 | <<locked>> | 84% | 57,029 psi | 89% | 3094 fps | 100% |
| Norma 203B | <<locked>> | 86% | 55,332 psi | 87% | 3133 fps | 100% |
| Norma 204 | <<locked>> | 96% | 56,956 psi | 89% | 3182 fps | 96.4% |
| Norma MRPᴾ | <<locked>> | 100% | 51,547 psi | 81% | 3196 fps | 97.2% |
| Norma URP | <<locked>> | 96% | 56,797 psi | 89% | 3196 fps | 99.7% |
| Ramshot Big Game | <<locked>> | 86% | 55,579 psi | 87% | 3153 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 96% | 55,579 psi | 87% | 3189 fps | 98.7% |
| Ramshot TAC | <<locked>> | 82% | 56,289 psi | 88% | 3110 fps | 99.1% |
| Ramshot Wild Boar | <<locked>> | 82% | 56,115 psi | 88% | 3130 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,854 psi | 58% | 1998 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 57,029 psi | 89% | 3130 fps | 98.6% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 56,449 psi | 88% | 3215 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 56,086 psi | 88% | 3248 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 94% | 54,360 psi | 85% | 3179 fps | 99.4% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 57,000 psi | 89% | 3268 fps | 99.6% |
| Rottweil R 902 | <<locked>> | 86% | 57,246 psi | 90% | 3094 fps | 100% |
| Rottweil R 903 | <<locked>> | 90% | 56,913 psi | 89% | 3136 fps | 100% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 54,027 psi | 85% | 3156 fps | 96.3% |
| Rottweil R 907 | <<locked>> | 92% | 55,970 psi | 88% | 3104 fps | 97.4% |
| Shooters World Long Rifle | <<locked>> | 92% | 54,389 psi | 85% | 3081 fps | 98.7% |
| Shooters World Match Rifle | <<locked>> | 82% | 54,578 psi | 86% | 3074 fps | 100% |
| Shooters World Precision | <<locked>> | 86% | 54,868 psi | 86% | 3077 fps | 100% |
| Shooters World SW4350 | <<locked>> | 94% | 55,651 psi | 87% | 3123 fps | 98.1% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 57,638 psi | 90% | 3192 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 82% | 55,347 psi | 87% | 3094 fps | 99.3% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 55,666 psi | 87% | 3114 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 57,145 psi | 90% | 3018 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 57,740 psi | 90% | 3018 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 92% | 54,302 psi | 85% | 3025 fps | 97.6% |
| SNPE Vectan Tubal 8000ᴾ | <<locked>> | 100% | 53,519 psi | 84% | 3153 fps | 96.1% |
| Somchem S335 | <<locked>> | 84% | 57,159 psi | 90% | 3022 fps | 100% |
| Somchem S341 | <<locked>> | 82% | 54,636 psi | 86% | 3077 fps | 99.9% |
| Somchem S355 | <<locked>> | 90% | 56,536 psi | 89% | 3130 fps | 100% |
| Somchem S365 | <<locked>> | 98% | 55,637 psi | 87% | 3205 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 54,998 psi | 86% | 3136 fps | 97.3% |
| Vihtavuori N133 | <<locked>> | 84% | 57,348 psi | 90% | 2999 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 57,159 psi | 90% | 3054 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 57,435 psi | 90% | 3068 fps | 100% |
| Vihtavuori N150 | <<locked>> | 90% | 54,607 psi | 86% | 3051 fps | 100% |
| Vihtavuori N160 | <<locked>> | 94% | 55,680 psi | 87% | 3136 fps | 99.6% |
| Vihtavuori N530 | <<locked>> | 82% | 56,637 psi | 89% | 3091 fps | 100% |
| Vihtavuori N540 | <<locked>> | 86% | 55,535 psi | 87% | 3061 fps | 100% |
| Vihtavuori N550 | <<locked>> | 94% | 54,897 psi | 86% | 3143 fps | 99.4% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 51,372 psi | 81% | 3143 fps | 99.6% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 55,317 psi | 87% | 3104 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 56,855 psi | 89% | 3143 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 57,261 psi | 90% | 3212 fps | 98.3% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 41,916 psi | 66% | 3094 fps | 99.9% |
| Winchester StaBALL Match | <<locked>> | 84% | 56,043 psi | 88% | 3127 fps | 100% |
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 2495 | <<locked>> | 80% | 49,516 psi | 78% | 2933 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 46,586 psi | 73% | 2890 fps | 95.1% |
| Accurate 3100 | <<locked>> | 94% | 40,828 psi | 64% | 2864 fps | 95.5% |
| Accurate 4064 | <<locked>> | 80% | 46,702 psi | 73% | 2933 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 35,186 psi | 55% | 2756 fps | 95.5% |
| ADI AR 2206H | <<locked>> | 80% | 50,981 psi | 80% | 3038 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 80% | 43,279 psi | 68% | 2871 fps | 98.4% |
| ADI AR 2209 | <<locked>> | 98% | 52,431 psi | 82% | 3123 fps | 95.5% |
| ADI Benchmark 8208 | <<locked>> | 80% | 52,866 psi | 83% | 3041 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 46,702 psi | 73% | 3081 fps | 99% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 51,692 psi | 81% | 3054 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 43,801 psi | 69% | 2907 fps | 99.5% |
| Alliant Reloder-15 | <<locked>> | 80% | 46,717 psi | 73% | 2976 fps | 99% |
| Alliant Reloder-16 | 35.2 gr | 80% | 34,200 psi | 54% | 2749 fps | 95.2% |
| Alliant Reloder-17 | <<locked>> | 80% | 38,406 psi | 60% | 2890 fps | 98.5% |
| Alliant Reloder-19 | <<locked>> | 98% | 51,547 psi | 81% | 3110 fps | 95.5% |
| Alliant Reloder-23 | <<locked>> | 86% | 30,705 psi | 48% | 2667 fps | 95.4% |
| Alliant Reloder-25 | <<locked>> | 98% | 38,566 psi | 60% | 2890 fps | 95.1% |
| Alliant Reloder-26 | <<locked>> | 90% | 37,463 psi | 59% | 2920 fps | 95.8% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 50,169 psi | 79% | 3041 fps | 99.2% |
| Bofors RP3 | <<locked>> | 80% | 44,295 psi | 69% | 2923 fps | 99.6% |
| Bofors RP7 | <<locked>> | 86% | 47,036 psi | 74% | 2936 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 80% | 54,041 psi | 85% | 3018 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 52,518 psi | 82% | 3068 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 44,570 psi | 70% | 2923 fps | 97.7% |
| Hodgdon H414 | <<locked>> | 86% | 44,208 psi | 69% | 2969 fps | 95.4% |
| Hodgdon H4350 | <<locked>> | 88% | 50,299 psi | 79% | 3045 fps | 95.5% |
| Hodgdon H4895 | <<locked>> | 80% | 51,547 psi | 81% | 3051 fps | 99.9% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 31,952 psi | 50% | 2648 fps | 96.3% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 47,732 psi | 75% | 3025 fps | 99.9% |
| Hodgdon Superformance | <<locked>> | 88% | 46,615 psi | 73% | 3045 fps | 95.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,253 psi | 43% | 1749 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 49,139 psi | 77% | 2995 fps | 99.8% |
| IMR 3031 | <<locked>> | 80% | 51,808 psi | 81% | 3041 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 45,498 psi | 71% | 2910 fps | 98.9% |
| IMR 4166 Enduron | <<locked>> | 80% | 47,688 psi | 75% | 2930 fps | 96.3% |
| IMR 4350 | <<locked>> | 90% | 47,152 psi | 74% | 2963 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 84% | 45,266 psi | 71% | 2907 fps | 95.5% |
| IMR 4831 | <<locked>> | 80% | 33,663 psi | 53% | 2700 fps | 95% |
| IMR 4895 | <<locked>> | 80% | 47,892 psi | 75% | 3009 fps | 99.5% |
| IMR 8208 XBR | <<locked>> | 80% | 52,866 psi | 83% | 3041 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 51,285 psi | 80% | 3022 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 50,082 psi | 78% | 2959 fps | 99.7% |
| Lovex S062 | <<locked>> | 80% | 46,122 psi | 72% | 2923 fps | 99.8% |
| Lovex S065 | <<locked>> | 80% | 38,392 psi | 60% | 2756 fps | 95.1% |
| Lovex S070 | <<locked>> | 86% | 43,903 psi | 69% | 2897 fps | 95.5% |
| Lovex S071 | <<locked>> | 98% | 39,117 psi | 61% | 2828 fps | 95% |
| Norma 201 | <<locked>> | 80% | 50,372 psi | 79% | 2992 fps | 100% |
| Norma 202 | <<locked>> | 80% | 50,488 psi | 79% | 2989 fps | 100% |
| Norma 203B | <<locked>> | 80% | 46,151 psi | 72% | 2966 fps | 99.3% |
| Norma 204 | <<locked>> | 94% | 53,432 psi | 84% | 3123 fps | 95.7% |
| Norma MRP | <<locked>> | 96% | 45,179 psi | 71% | 3064 fps | 95.5% |
| Norma URP | <<locked>> | 80% | 34,737 psi | 54% | 2743 fps | 95.2% |
| Ramshot Big Game | <<locked>> | 80% | 45,658 psi | 72% | 2972 fps | 99.2% |
| Ramshot Hunter | <<locked>> | 86% | 40,785 psi | 64% | 2897 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 52,779 psi | 83% | 3051 fps | 98.6% |
| Ramshot Wild Boar | <<locked>> | 80% | 52,852 psi | 83% | 3077 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,630 psi | 43% | 1788 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 44,396 psi | 70% | 2894 fps | 96.1% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 49,734 psi | 78% | 3097 fps | 99.4% |
| ReloadSwiss RS 60 | 38 gr | 80% | 40,625 psi | 64% | 2956 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 82% | 36,811 psi | 58% | 2822 fps | 95.7% |
| ReloadSwiss RS 70 | 40.5 gr | 84% | 38,580 psi | 60% | 2881 fps | 95.6% |
| Rottweil R 902 | <<locked>> | 80% | 48,124 psi | 75% | 2940 fps | 99.9% |
| Rottweil R 903 | <<locked>> | 80% | 41,800 psi | 66% | 2864 fps | 99.1% |
| Rottweil R 905 | <<locked>> | 98% | 50,662 psi | 79% | 3097 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 86% | 47,036 psi | 74% | 2936 fps | 95.5% |
| Shooters World Long Rifle | <<locked>> | 80% | 38,392 psi | 60% | 2756 fps | 95.1% |
| Shooters World Match Rifle | <<locked>> | 80% | 51,285 psi | 80% | 3022 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 46,122 psi | 72% | 2923 fps | 99.8% |
| Shooters World SW4350 | <<locked>> | 86% | 43,903 psi | 69% | 2897 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 42,235 psi | 66% | 2910 fps | 98.6% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 51,764 psi | 81% | 3031 fps | 98.9% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 49,443 psi | 77% | 3005 fps | 99.6% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 50,792 psi | 80% | 2920 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 42,902 psi | 67% | 2779 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 45,266 psi | 71% | 2861 fps | 95.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 50,183 psi | 79% | 3091 fps | 95.3% |
| Somchem S335 | <<locked>> | 80% | 50,836 psi | 80% | 2923 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 51,053 psi | 80% | 3018 fps | 99.7% |
| Somchem S355 | <<locked>> | 80% | 42,105 psi | 66% | 2864 fps | 99% |
| Somchem S365 | <<locked>> | 80% | 31,589 psi | 50% | 2700 fps | 97.6% |
| Somchem S385 | <<locked>> | 94% | 45,730 psi | 72% | 2966 fps | 95.1% |
| Vihtavuori N133 | <<locked>> | 80% | 51,053 psi | 80% | 2907 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 47,674 psi | 75% | 2910 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 47,921 psi | 75% | 2917 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 40,103 psi | 63% | 2789 fps | 99.5% |
| Vihtavuori N160 | <<locked>> | 80% | 36,056 psi | 56% | 2743 fps | 95.6% |
| Vihtavuori N530 | <<locked>> | 80% | 53,258 psi | 83% | 3038 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 46,470 psi | 73% | 2910 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 35,810 psi | 56% | 2746 fps | 95.3% |
| Vihtavuori N555 | <<locked>> | 86% | 33,330 psi | 52% | 2753 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 35,389 psi | 55% | 2710 fps | 97.8% |
| Winchester 748 | <<locked>> | 80% | 53,490 psi | 84% | 3091 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 44,483 psi | 70% | 2972 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 90% | 30,850 psi | 48% | 2756 fps | 96.2% |
| Winchester StaBALL Match | <<locked>> | 80% | 49,023 psi | 77% | 3009 fps | 99.8% |
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 115 powders for .243 WSSM loaded with the .243 | 90gr | Barnes X S. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,274 fps; across all powders the maximum-charge window runs from 1,952 fps to 3,274 fps. Accurate 3100 gives the best case fill at 100 %, and 115 of the 115 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 90.0 gr projectile in 0.243" calls for a 1:9.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate High Country, Accurate MAGPRO 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. ReloadSwiss RS 60, ReloadSwiss RS 70, Alliant Reloder-16 rank at the top here: for .243 WSSM with the .243 | 90gr | Barnes X S they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate High Country, Accurate MAGPRO, ADI AR 2213 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.