Load Specifications
Load data in caliber .243 WSSM with .243 | 85gr | Sierra VarmintKing bullet and 95 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Hodgdon Superformance and Alliant Reloder-17.
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 2015 | <<locked>> | 82% | 54,882 psi | 86% | 3097 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 53,911 psi | 84% | 3117 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 55,332 psi | 87% | 3186 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 56,507 psi | 89% | 3173 fps | 97% |
| Accurate 3100ᴾ | <<locked>> | 100% | 45,049 psi | 71% | 3051 fps | 96.4% |
| Accurate 4064 | <<locked>> | 88% | 54,346 psi | 85% | 3173 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 54,346 psi | 85% | 3255 fps | 99.4% |
| ADI AR 2206H | <<locked>> | 86% | 57,493 psi | 90% | 3258 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 55,317 psi | 87% | 3202 fps | 99.7% |
| ADI Benchmark 8208 | <<locked>> | 84% | 56,434 psi | 88% | 3205 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 57,667 psi | 90% | 3179 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 54,070 psi | 85% | 3330 fps | 99.7% |
| Alliant Power Pro Varmint | <<locked>> | 84% | 54,824 psi | 86% | 3215 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 55,419 psi | 87% | 3225 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 56,086 psi | 88% | 3251 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 98% | 55,492 psi | 87% | 3323 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 94% | 56,695 psi | 89% | 3360 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 42,627 psi | 67% | 3081 fps | 99.1% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 48,211 psi | 76% | 3268 fps | 98.6% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 57,696 psi | 90% | 3274 fps | 99.7% |
| Bofors RP3 | <<locked>> | 90% | 56,449 psi | 88% | 3248 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 56,231 psi | 88% | 3209 fps | 97.2% |
| Hodgdon Benchmark | <<locked>> | 82% | 54,607 psi | 86% | 3133 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 56,376 psi | 88% | 3238 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 57,029 psi | 89% | 3255 fps | 99.4% |
| Hodgdon H414 | <<locked>> | 96% | 57,130 psi | 90% | 3310 fps | 98% |
| Hodgdon H4350 | <<locked>> | 94% | 57,522 psi | 90% | 3271 fps | 96.8% |
| Hodgdon H4895 | <<locked>> | 84% | 54,665 psi | 86% | 3215 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 55,506 psi | 87% | 3241 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 54,288 psi | 85% | 3245 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 54,012 psi | 85% | 3284 fps | 97.1% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,549 psi | 56% | 2018 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 55,811 psi | 87% | 3215 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 54,955 psi | 86% | 3199 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 54,795 psi | 86% | 3186 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 86% | 54,288 psi | 85% | 3153 fps | 97.3% |
| IMR 4350 | <<locked>> | 98% | 56,594 psi | 89% | 3235 fps | 97.3% |
| IMR 4451 Enduron | <<locked>> | 92% | 54,346 psi | 85% | 3182 fps | 97.3% |
| IMR 4831 | <<locked>> | 98% | 55,071 psi | 86% | 3251 fps | 99.5% |
| IMR 4895 | <<locked>> | 88% | 57,508 psi | 90% | 3287 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 56,434 psi | 88% | 3205 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 54,070 psi | 85% | 3176 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 56,623 psi | 89% | 3176 fps | 99.9% |
| Lovex S062 | <<locked>> | 88% | 54,462 psi | 85% | 3176 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 57,348 psi | 90% | 3235 fps | 98.9% |
| Lovex S070 | <<locked>> | 96% | 55,027 psi | 86% | 3215 fps | 97.8% |
| Norma 201 | <<locked>> | 86% | 56,072 psi | 88% | 3196 fps | 100% |
| Norma 202 | <<locked>> | 86% | 56,985 psi | 89% | 3199 fps | 100% |
| Norma 203B | <<locked>> | 88% | 55,303 psi | 87% | 3238 fps | 99.9% |
| Norma URP | <<locked>> | 98% | 57,116 psi | 90% | 3304 fps | 99.6% |
| Ramshot Big Game | <<locked>> | 88% | 56,086 psi | 88% | 3264 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 98% | 55,985 psi | 88% | 3297 fps | 98.5% |
| Ramshot TAC | <<locked>> | 84% | 56,855 psi | 89% | 3222 fps | 99% |
| Ramshot Wild Boar | <<locked>> | 84% | 56,608 psi | 89% | 3241 fps | 99.9% |
| Ramshot X-Terminator | <<locked>> | 82% | 57,029 psi | 89% | 3199 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,042 psi | 56% | 2067 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 57,261 psi | 90% | 3235 fps | 98.4% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 56,478 psi | 89% | 3320 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 56,637 psi | 89% | 3363 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 54,317 psi | 85% | 3278 fps | 99.3% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 57,508 psi | 90% | 3376 fps | 99.5% |
| Rottweil R 901 | <<locked>> | 84% | 56,985 psi | 89% | 3179 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 56,855 psi | 89% | 3199 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 56,304 psi | 88% | 3238 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 56,231 psi | 88% | 3209 fps | 97.2% |
| Shooters World Long Rifle | <<locked>> | 96% | 57,348 psi | 90% | 3235 fps | 98.9% |
| Shooters World Match Rifle | <<locked>> | 84% | 54,070 psi | 85% | 3176 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 54,462 psi | 85% | 3176 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 55,027 psi | 86% | 3215 fps | 97.8% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 54,389 psi | 85% | 3241 fps | 99.9% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 55,521 psi | 87% | 3199 fps | 99.1% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 55,898 psi | 88% | 3222 fps | 99.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 57,377 psi | 90% | 3130 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 54,549 psi | 85% | 3077 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 54,302 psi | 85% | 3127 fps | 97.4% |
| Somchem S335 | <<locked>> | 86% | 56,811 psi | 89% | 3123 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 55,042 psi | 86% | 3189 fps | 99.9% |
| Somchem S355 | <<locked>> | 92% | 56,275 psi | 88% | 3232 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 55,593 psi | 87% | 3307 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 51,155 psi | 80% | 3166 fps | 96.2% |
| Vihtavuori N130 | <<locked>> | 82% | 57,217 psi | 90% | 3094 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 57,667 psi | 90% | 3110 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 56,652 psi | 89% | 3156 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 57,435 psi | 90% | 3173 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 54,360 psi | 85% | 3153 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 55,666 psi | 87% | 3238 fps | 99.4% |
| Vihtavuori N530 | <<locked>> | 84% | 56,884 psi | 89% | 3202 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 55,869 psi | 88% | 3169 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 54,882 psi | 86% | 3241 fps | 99.3% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 47,253 psi | 74% | 3169 fps | 99% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 56,202 psi | 88% | 3212 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 57,130 psi | 90% | 3255 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 57,537 psi | 90% | 3317 fps | 98.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 38,203 psi | 60% | 3087 fps | 99.1% |
| Winchester StaBALL Match | <<locked>> | 86% | 56,043 psi | 88% | 3232 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 2015 | <<locked>> | 80% | 51,561 psi | 81% | 3045 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 44,411 psi | 70% | 2959 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 51,982 psi | 81% | 3133 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 49,385 psi | 77% | 3045 fps | 95.4% |
| Accurate 3100 | <<locked>> | 98% | 42,076 psi | 66% | 2989 fps | 95.5% |
| Accurate 4064 | <<locked>> | 80% | 41,959 psi | 66% | 2953 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 35,781 psi | 56% | 2871 fps | 95.3% |
| ADI AR 2206H | <<locked>> | 80% | 47,572 psi | 75% | 3081 fps | 99.3% |
| ADI AR 2208 | <<locked>> | 80% | 40,408 psi | 63% | 2907 fps | 97.4% |
| ADI Benchmark 8208 | <<locked>> | 80% | 49,647 psi | 78% | 3087 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 50,575 psi | 79% | 3074 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 43,758 psi | 69% | 3120 fps | 98.1% |
| Alliant Power Pro Varmint | <<locked>> | 80% | 48,167 psi | 75% | 3094 fps | 99.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 40,321 psi | 63% | 2936 fps | 98.7% |
| Alliant Reloder-15 | <<locked>> | 80% | 43,207 psi | 68% | 3005 fps | 98.2% |
| Alliant Reloder-16 | <<locked>> | 84% | 35,621 psi | 56% | 2884 fps | 95.3% |
| Alliant Reloder-17 | 39.4 gr | 80% | 34,896 psi | 55% | 2890 fps | 96.9% |
| Alliant Reloder-23 | <<locked>> | 90% | 31,053 psi | 49% | 2772 fps | 95% |
| Alliant Reloder-26 | <<locked>> | 94% | 38,841 psi | 61% | 3048 fps | 95.9% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 47,195 psi | 74% | 3084 fps | 98.5% |
| Bofors RP3 | <<locked>> | 80% | 40,176 psi | 63% | 2940 fps | 98.8% |
| Bofors RP7 | <<locked>> | 90% | 49,385 psi | 77% | 3087 fps | 95.7% |
| Hodgdon Benchmark | <<locked>> | 80% | 51,097 psi | 80% | 3074 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 49,182 psi | 77% | 3114 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 40,843 psi | 64% | 2940 fps | 96.4% |
| Hodgdon H414 | <<locked>> | 90% | 46,688 psi | 73% | 3117 fps | 95.7% |
| Hodgdon H4350 | <<locked>> | 90% | 50,575 psi | 79% | 3146 fps | 95.2% |
| Hodgdon H4895 | <<locked>> | 80% | 48,022 psi | 75% | 3094 fps | 99.6% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 30,676 psi | 48% | 2707 fps | 95.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 44,353 psi | 70% | 3061 fps | 99.4% |
| Hodgdon Superformance | 46.9 gr | 90% | 46,630 psi | 73% | 3136 fps | 95.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,643 psi | 42% | 1811 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 46,093 psi | 72% | 3038 fps | 99.4% |
| IMR 3031 | <<locked>> | 80% | 47,863 psi | 75% | 3087 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 42,453 psi | 67% | 2949 fps | 98.1% |
| IMR 4166 Enduron | <<locked>> | 80% | 44,976 psi | 70% | 2972 fps | 95.1% |
| IMR 4350 | <<locked>> | 92% | 46,833 psi | 73% | 3054 fps | 95% |
| IMR 4451 Enduron | <<locked>> | 86% | 45,092 psi | 71% | 3002 fps | 95% |
| IMR 4831 | <<locked>> | 86% | 37,043 psi | 58% | 2884 fps | 95.9% |
| IMR 4895 | <<locked>> | 80% | 44,266 psi | 69% | 3041 fps | 98.8% |
| IMR 8208 XBR | <<locked>> | 80% | 49,647 psi | 78% | 3087 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 47,369 psi | 74% | 3061 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 47,268 psi | 74% | 3012 fps | 99.3% |
| Lovex S062 | <<locked>> | 80% | 42,540 psi | 67% | 2956 fps | 99.3% |
| Lovex S065 | <<locked>> | 84% | 39,581 psi | 62% | 2884 fps | 95% |
| Lovex S070 | <<locked>> | 90% | 45,484 psi | 71% | 3031 fps | 95.6% |
| Norma 201 | <<locked>> | 80% | 46,615 psi | 73% | 3028 fps | 99.7% |
| Norma 202 | <<locked>> | 80% | 47,050 psi | 74% | 3035 fps | 100% |
| Norma 203B | <<locked>> | 80% | 42,569 psi | 67% | 2992 fps | 98.5% |
| Norma URP | <<locked>> | 84% | 35,955 psi | 56% | 2874 fps | 95.2% |
| Ramshot Big Game | <<locked>> | 80% | 42,554 psi | 67% | 3009 fps | 98.4% |
| Ramshot Hunter | <<locked>> | 90% | 42,772 psi | 67% | 3041 fps | 95.6% |
| Ramshot TAC | <<locked>> | 80% | 49,893 psi | 78% | 3097 fps | 97.9% |
| Ramshot Wild Boar | <<locked>> | 80% | 49,516 psi | 78% | 3117 fps | 99.5% |
| Ramshot X-Terminator | <<locked>> | 80% | 53,447 psi | 84% | 3140 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,890 psi | 42% | 1850 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 44,048 psi | 69% | 2986 fps | 95.6% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 45,876 psi | 72% | 3123 fps | 98.6% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 37,115 psi | 58% | 2969 fps | 99.5% |
| ReloadSwiss RS 62 | <<locked>> | 86% | 38,218 psi | 60% | 2953 fps | 95.8% |
| ReloadSwiss RS 70 | 44.1 gr | 88% | 40,611 psi | 64% | 3025 fps | 95.9% |
| Rottweil R 901 | <<locked>> | 80% | 50,473 psi | 79% | 3071 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 44,454 psi | 70% | 2976 fps | 99.5% |
| Rottweil R 903 | <<locked>> | 80% | 37,811 psi | 59% | 2874 fps | 98% |
| Rottweil R 907 | <<locked>> | 90% | 49,385 psi | 77% | 3087 fps | 95.7% |
| Shooters World Long Rifle | <<locked>> | 84% | 39,581 psi | 62% | 2884 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 47,369 psi | 74% | 3061 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 42,540 psi | 67% | 2956 fps | 99.3% |
| Shooters World SW4350 | <<locked>> | 90% | 45,484 psi | 71% | 3031 fps | 95.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 38,711 psi | 61% | 2927 fps | 97.5% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 48,080 psi | 75% | 3064 fps | 98% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 46,021 psi | 72% | 3041 fps | 99% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 47,834 psi | 75% | 2976 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 40,030 psi | 63% | 2825 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 44,672 psi | 70% | 2946 fps | 95.1% |
| Somchem S335 | <<locked>> | 80% | 47,427 psi | 74% | 2972 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 48,008 psi | 75% | 3064 fps | 99.3% |
| Somchem S355 | <<locked>> | 80% | 38,522 psi | 60% | 2884 fps | 98% |
| Somchem S365 | <<locked>> | 80% | 28,108 psi | 44% | 2684 fps | 95.4% |
| Somchem S385 | <<locked>> | 98% | 48,037 psi | 75% | 3107 fps | 95.4% |
| Vihtavuori N130 | <<locked>> | 80% | 53,809 psi | 84% | 3041 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 48,225 psi | 76% | 2969 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 44,121 psi | 69% | 2956 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 44,541 psi | 70% | 2963 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 36,637 psi | 57% | 2812 fps | 98.7% |
| Vihtavuori N160 | <<locked>> | 84% | 37,449 psi | 59% | 2874 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 80% | 49,835 psi | 78% | 3087 fps | 99.9% |
| Vihtavuori N540 | <<locked>> | 80% | 42,946 psi | 67% | 2946 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 36,782 psi | 58% | 2867 fps | 95.2% |
| Vihtavuori N555 | <<locked>> | 90% | 33,794 psi | 53% | 2858 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 32,590 psi | 51% | 2723 fps | 96.3% |
| Winchester 748 | <<locked>> | 80% | 50,096 psi | 79% | 3140 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 47,021 psi | 74% | 3123 fps | 95.8% |
| Winchester StaBALL HD | <<locked>> | 94% | 31,299 psi | 49% | 2858 fps | 95.8% |
| Winchester StaBALL Match | <<locked>> | 80% | 45,934 psi | 72% | 3051 fps | 99.4% |
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 95 powders for .243 WSSM loaded with the .243 | 85gr | Sierra VarmintKing. ReloadSwiss RS 70 delivers the highest muzzle velocity at 3,376 fps; across all powders the maximum-charge window runs from 2,018 fps to 3,376 fps. Accurate 3100 gives the best case fill at 100 %, and 95 of the 95 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 56–90 %, 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, Alliant Reloder-26 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 70, Hodgdon Superformance, Alliant Reloder-17 rank at the top here: for .243 WSSM 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.