Load Specifications
Load data in caliber .25 WSSM with .257 | 88gr | Osprey Virtus bullet and 94 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Power Pro 2000-MR, ReloadSwiss RS 52 and Hodgdon LEVERevolution.
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>> | 90% | 56,043 psi | 88% | 3192 fps | 100% |
| Accurate 2200 | <<locked>> | 82% | 56,246 psi | 88% | 3297 fps | 98.4% |
| Accurate 2230 | <<locked>> | 82% | 57,435 psi | 90% | 3307 fps | 98.9% |
| Accurate 2460 | <<locked>> | 86% | 54,563 psi | 86% | 3212 fps | 100% |
| Accurate 2495 | <<locked>> | 96% | 57,014 psi | 89% | 3251 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 54,476 psi | 85% | 3255 fps | 100% |
| Accurate 4064 | <<locked>> | 98% | 56,695 psi | 89% | 3294 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 45,701 psi | 72% | 3159 fps | 96.1% |
| Accurate LT-30 | <<locked>> | 84% | 55,898 psi | 88% | 3140 fps | 100% |
| Accurate LT-32 | <<locked>> | 84% | 56,304 psi | 88% | 3166 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 55,347 psi | 87% | 3281 fps | 99% |
| ADI AR 2207 | <<locked>> | 82% | 57,421 psi | 90% | 3166 fps | 100% |
| ADI AR 2208 | <<locked>> | 98% | 56,333 psi | 88% | 3271 fps | 98.6% |
| ADI AR 2219 | <<locked>> | 84% | 56,869 psi | 89% | 3271 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 54,665 psi | 86% | 3235 fps | 99.6% |
| Alliant AR-Comp | <<locked>> | 90% | 54,505 psi | 85% | 3228 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 56,188 psi | 88% | 3360 fps | 99.4% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 55,085 psi | 86% | 3392 fps | 98.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 98% | 55,564 psi | 87% | 3291 fps | 99.5% |
| Alliant Reloder-10x | <<locked>> | 86% | 56,086 psi | 88% | 3209 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 56,434 psi | 88% | 3317 fps | 98.8% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 45,701 psi | 72% | 3169 fps | 96.1% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 53,113 psi | 83% | 3353 fps | 99.2% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 55,506 psi | 87% | 3130 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 55,463 psi | 87% | 3291 fps | 98.2% |
| Bofors RP3 | <<locked>> | 98% | 55,985 psi | 88% | 3307 fps | 99.6% |
| Hodgdon Benchmark | <<locked>> | 90% | 56,971 psi | 89% | 3228 fps | 99.9% |
| Hodgdon BL-C2 | <<locked>> | 92% | 57,653 psi | 90% | 3327 fps | 99.9% |
| Hodgdon CFE223 | <<locked>> | 88% | 55,477 psi | 87% | 3366 fps | 98.7% |
| Hodgdon H322 | <<locked>> | 86% | 55,259 psi | 87% | 3245 fps | 100% |
| Hodgdon H335 | <<locked>> | 86% | 56,898 psi | 89% | 3274 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 54,201 psi | 85% | 3258 fps | 97.3% |
| Hodgdon H4895 | <<locked>> | 92% | 55,811 psi | 87% | 3291 fps | 99.4% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 41,684 psi | 65% | 3038 fps | 96.8% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 54,665 psi | 86% | 3320 fps | 99.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,316 psi | 54% | 2011 fps | 100% |
| Hodgdon VARGET | <<locked>> | 94% | 57,653 psi | 90% | 3301 fps | 99.5% |
| IMR 3031 | <<locked>> | 92% | 55,013 psi | 86% | 3287 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 56,086 psi | 88% | 3258 fps | 98.7% |
| IMR 4198 | <<locked>> | 86% | 56,289 psi | 88% | 3169 fps | 100% |
| IMR 4895 | <<locked>> | 94% | 54,288 psi | 85% | 3294 fps | 98.9% |
| IMR 8208 XBR | <<locked>> | 90% | 54,665 psi | 86% | 3235 fps | 99.6% |
| Lovex D073.5 | <<locked>> | 86% | 54,607 psi | 86% | 3219 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 92% | 54,476 psi | 85% | 3255 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 55,753 psi | 87% | 3209 fps | 99% |
| Lovex S062 | <<locked>> | 96% | 54,955 psi | 86% | 3248 fps | 99.6% |
| Lovex S065ᴾ | <<locked>> | 100% | 51,082 psi | 80% | 3169 fps | 95.8% |
| Norma 200 | <<locked>> | 82% | 55,405 psi | 87% | 3173 fps | 100% |
| Norma 201 | <<locked>> | 94% | 57,464 psi | 90% | 3281 fps | 99.8% |
| Norma 202 | <<locked>> | 92% | 54,288 psi | 85% | 3232 fps | 100% |
| Norma 203B | <<locked>> | 96% | 55,506 psi | 87% | 3301 fps | 99% |
| Norma URPᴾ | <<locked>> | 100% | 45,818 psi | 72% | 3156 fps | 96% |
| Ramshot Big Game | <<locked>> | 96% | 56,623 psi | 89% | 3333 fps | 99.1% |
| Ramshot TAC | <<locked>> | 90% | 55,492 psi | 87% | 3241 fps | 96.9% |
| Ramshot Wild Boar | <<locked>> | 90% | 54,505 psi | 85% | 3264 fps | 98.8% |
| Ramshot X-Terminator | <<locked>> | 88% | 56,275 psi | 88% | 3238 fps | 99% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,534 psi | 54% | 2057 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 54,230 psi | 85% | 3222 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 54,969 psi | 86% | 3235 fps | 95.8% |
| ReloadSwiss RS 52 | <<locked>> | 94% | 56,666 psi | 89% | 3389 fps | 98.8% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 56,811 psi | 89% | 3432 fps | 100% |
| Rottweil R 901 | <<locked>> | 90% | 54,447 psi | 85% | 3212 fps | 100% |
| Rottweil R 902 | <<locked>> | 94% | 54,288 psi | 85% | 3215 fps | 99.6% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 55,883 psi | 88% | 3294 fps | 99.5% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 51,082 psi | 80% | 3169 fps | 95.8% |
| Shooters World Match Rifle | <<locked>> | 92% | 54,476 psi | 85% | 3255 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 54,955 psi | 86% | 3248 fps | 99.6% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 54,505 psi | 85% | 3189 fps | 99.4% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 55,883 psi | 88% | 2874 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 84% | 57,377 psi | 90% | 3281 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 54,375 psi | 85% | 3304 fps | 98.9% |
| SNPE Vectan SP 3 | <<locked>> | 86% | 56,913 psi | 89% | 3228 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 92% | 57,392 psi | 90% | 3274 fps | 97.7% |
| SNPE Vectan SP 9 | <<locked>> | 94% | 57,479 psi | 90% | 3304 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 56,072 psi | 88% | 3173 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 55,927 psi | 88% | 3163 fps | 100% |
| Somchem S321 | <<locked>> | 88% | 55,999 psi | 88% | 3271 fps | 99.8% |
| Somchem S335 | <<locked>> | 92% | 55,143 psi | 86% | 3166 fps | 100% |
| Somchem S341 | <<locked>> | 92% | 56,681 psi | 89% | 3268 fps | 99.1% |
| Somchem S355ᴾ | <<locked>> | 100% | 56,478 psi | 89% | 3294 fps | 99.4% |
| Somchem S365ᴾ | <<locked>> | 100% | 40,524 psi | 64% | 3087 fps | 98% |
| Vihtavuori N120 | <<locked>> | 82% | 57,276 psi | 90% | 3104 fps | 100% |
| Vihtavuori N130 | <<locked>> | 88% | 55,912 psi | 88% | 3146 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 56,043 psi | 88% | 3159 fps | 100% |
| Vihtavuori N135 | <<locked>> | 96% | 57,058 psi | 89% | 3245 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 55,172 psi | 86% | 3212 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 54,795 psi | 86% | 3222 fps | 99.8% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 48,443 psi | 76% | 3163 fps | 96.5% |
| Vihtavuori N530 | <<locked>> | 90% | 55,158 psi | 86% | 3235 fps | 99.6% |
| Vihtavuori N540 | <<locked>> | 96% | 56,971 psi | 89% | 3258 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 47,529 psi | 74% | 3163 fps | 96.1% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 49,690 psi | 78% | 3146 fps | 98.7% |
| Winchester 748 | <<locked>> | 90% | 54,520 psi | 85% | 3284 fps | 99.9% |
| Winchester StaBALL Match | <<locked>> | 94% | 57,609 psi | 90% | 3317 fps | 99.5% |
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% | 40,524 psi | 64% | 2923 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 52,678 psi | 83% | 3232 fps | 97.9% |
| Accurate 2230 | <<locked>> | 80% | 53,301 psi | 84% | 3238 fps | 98.3% |
| Accurate 2460 | <<locked>> | 80% | 44,498 psi | 70% | 3031 fps | 99.6% |
| Accurate 2495 | <<locked>> | 80% | 32,692 psi | 51% | 2792 fps | 99.6% |
| Accurate 2520 | <<locked>> | 80% | 38,058 psi | 60% | 2940 fps | 98.3% |
| Accurate 4064 | <<locked>> | 80% | 30,922 psi | 48% | 2762 fps | 97.2% |
| Accurate 4350 | <<locked>> | 98% | 42,482 psi | 67% | 3091 fps | 95.1% |
| Accurate LT-30 | <<locked>> | 80% | 49,530 psi | 78% | 3035 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 49,908 psi | 78% | 3058 fps | 99.8% |
| ADI AR 2206H | <<locked>> | 82% | 39,885 psi | 63% | 2969 fps | 95.8% |
| ADI AR 2207 | <<locked>> | 80% | 53,809 psi | 84% | 3110 fps | 100% |
| ADI AR 2208 | <<locked>> | 88% | 41,234 psi | 65% | 2976 fps | 95.4% |
| ADI AR 2219 | <<locked>> | 80% | 49,458 psi | 78% | 3150 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 39,450 psi | 62% | 2933 fps | 97% |
| Alliant AR-Comp | <<locked>> | 80% | 38,261 psi | 60% | 2949 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 45,614 psi | 71% | 3159 fps | 97.9% |
| Alliant Power Pro 2000-MR | 42.8 gr | 88% | 44,701 psi | 70% | 3179 fps | 96% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 35,143 psi | 55% | 2871 fps | 95.3% |
| Alliant Reloder-10x | <<locked>> | 80% | 46,354 psi | 73% | 3048 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 40,857 psi | 64% | 3009 fps | 95.5% |
| Alliant Reloder-16 | <<locked>> | 98% | 42,844 psi | 67% | 3104 fps | 95.2% |
| Alliant Reloder-17 | <<locked>> | 90% | 37,565 psi | 59% | 3005 fps | 95.2% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 48,573 psi | 76% | 3022 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 42,090 psi | 66% | 3028 fps | 95.1% |
| Bofors RP3 | <<locked>> | 84% | 34,548 psi | 54% | 2867 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 41,698 psi | 65% | 2943 fps | 98.1% |
| Hodgdon BL-C2 | <<locked>> | 80% | 37,594 psi | 59% | 2940 fps | 97.2% |
| Hodgdon CFE223 | <<locked>> | 80% | 41,437 psi | 65% | 3084 fps | 95.6% |
| Hodgdon H322 | <<locked>> | 80% | 45,237 psi | 71% | 3071 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 45,948 psi | 72% | 3087 fps | 99.8% |
| Hodgdon H380 | <<locked>> | 92% | 47,123 psi | 74% | 3127 fps | 95.8% |
| Hodgdon H4895 | <<locked>> | 80% | 37,652 psi | 59% | 2920 fps | 95.7% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 36,550 psi | 57% | 2913 fps | 95% |
| Hodgdon LEVERevolution | 39.1 gr | 82% | 36,158 psi | 57% | 2933 fps | 95.7% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,295 psi | 40% | 1798 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 36,419 psi | 57% | 2871 fps | 95.2% |
| IMR 3031 | <<locked>> | 80% | 36,564 psi | 57% | 2940 fps | 99.6% |
| IMR 4064 | <<locked>> | 86% | 40,538 psi | 64% | 2956 fps | 95.4% |
| IMR 4198 | <<locked>> | 80% | 47,181 psi | 74% | 3025 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 39,204 psi | 61% | 2986 fps | 95.7% |
| IMR 8208 XBR | <<locked>> | 80% | 39,450 psi | 62% | 2933 fps | 97% |
| Lovex D073.5 | <<locked>> | 80% | 44,222 psi | 69% | 3031 fps | 98.9% |
| Lovex D073.6 | <<locked>> | 80% | 35,563 psi | 56% | 2881 fps | 97.6% |
| Lovex S060 | <<locked>> | 80% | 38,189 psi | 60% | 2858 fps | 95.3% |
| Lovex S062 | <<locked>> | 82% | 35,070 psi | 55% | 2838 fps | 95.8% |
| Lovex S065 | <<locked>> | 98% | 47,921 psi | 75% | 3107 fps | 95% |
| Norma 200 | <<locked>> | 80% | 51,909 psi | 81% | 3117 fps | 100% |
| Norma 201 | <<locked>> | 80% | 36,448 psi | 57% | 2861 fps | 96.2% |
| Norma 202 | <<locked>> | 80% | 36,608 psi | 57% | 2884 fps | 98.5% |
| Norma 203B | <<locked>> | 84% | 37,579 psi | 59% | 2933 fps | 95% |
| Norma URP | <<locked>> | 98% | 42,902 psi | 67% | 3094 fps | 95.1% |
| Ramshot Big Game | <<locked>> | 86% | 39,798 psi | 62% | 3002 fps | 95.5% |
| Ramshot TAC | <<locked>> | 86% | 48,356 psi | 76% | 3110 fps | 95.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 38,508 psi | 60% | 2940 fps | 95.3% |
| Ramshot X-Terminator | <<locked>> | 80% | 43,033 psi | 67% | 2989 fps | 96.5% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,338 psi | 40% | 1837 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 44,367 psi | 70% | 3038 fps | 99.2% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 51,561 psi | 81% | 3176 fps | 95% |
| ReloadSwiss RS 52 | 39.6 gr | 84% | 39,668 psi | 62% | 3051 fps | 95% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 32,634 psi | 51% | 2877 fps | 95.8% |
| Rottweil R 901 | <<locked>> | 80% | 40,030 psi | 63% | 2933 fps | 98.9% |
| Rottweil R 902 | <<locked>> | 80% | 34,650 psi | 54% | 2805 fps | 95.5% |
| Rottweil R 903 | <<locked>> | 88% | 36,898 psi | 58% | 2920 fps | 95.7% |
| Shooters World Long Rifle | <<locked>> | 98% | 47,921 psi | 75% | 3107 fps | 95% |
| Shooters World Match Rifle | <<locked>> | 80% | 35,563 psi | 56% | 2881 fps | 97.6% |
| Shooters World Precision | <<locked>> | 82% | 35,070 psi | 55% | 2838 fps | 95.8% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 47,166 psi | 74% | 3061 fps | 98.4% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 53,200 psi | 83% | 2838 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 49,879 psi | 78% | 3156 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 38,827 psi | 61% | 2986 fps | 95.3% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 46,891 psi | 73% | 3068 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 46,151 psi | 72% | 3074 fps | 95.3% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 38,725 psi | 61% | 2933 fps | 95.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 38,218 psi | 60% | 2841 fps | 98.8% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 31,270 psi | 49% | 2677 fps | 98% |
| Somchem S321 | <<locked>> | 80% | 42,453 psi | 67% | 3018 fps | 98.1% |
| Somchem S335 | <<locked>> | 80% | 37,681 psi | 59% | 2841 fps | 99.2% |
| Somchem S341 | <<locked>> | 82% | 39,958 psi | 63% | 2949 fps | 95.7% |
| Somchem S355 | <<locked>> | 86% | 35,708 psi | 56% | 2874 fps | 95% |
| Somchem S365 | <<locked>> | 94% | 33,272 psi | 52% | 2894 fps | 95.3% |
| Vihtavuori N120 | <<locked>> | 80% | 53,664 psi | 84% | 3054 fps | 100% |
| Vihtavuori N130 | <<locked>> | 80% | 43,439 psi | 68% | 2940 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 38,348 psi | 60% | 2848 fps | 99.9% |
| Vihtavuori N135 | <<locked>> | 80% | 33,475 psi | 52% | 2805 fps | 99.6% |
| Vihtavuori N140 | <<locked>> | 80% | 34,592 psi | 54% | 2812 fps | 98.3% |
| Vihtavuori N150 | <<locked>> | 84% | 31,749 psi | 50% | 2743 fps | 95.1% |
| Vihtavuori N160 | <<locked>> | 98% | 45,324 psi | 71% | 3100 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 80% | 39,334 psi | 62% | 2927 fps | 97.1% |
| Vihtavuori N540 | <<locked>> | 80% | 33,315 psi | 52% | 2789 fps | 97.5% |
| Vihtavuori N550 | <<locked>> | 98% | 44,179 psi | 69% | 3097 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 37,840 psi | 59% | 2897 fps | 95.6% |
| Winchester 748 | <<locked>> | 80% | 38,276 psi | 60% | 2963 fps | 97.6% |
| Winchester StaBALL Match | <<locked>> | 82% | 37,869 psi | 59% | 2933 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 94 powders for .25 WSSM loaded with the .257 | 88gr | Osprey Virtus. ReloadSwiss RS 60 delivers the highest muzzle velocity at 3,432 fps; across all powders the maximum-charge window runs from 2,011 fps to 3,432 fps. Accurate 4350 gives the best case fill at 100 %, and 94 of the 94 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 54–90 %, leaving at least 10 % headroom. The 88.0 gr projectile in 0.257" calls for a 1:10.5 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-17 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 Power Pro 2000-MR, ReloadSwiss RS 52, Hodgdon LEVERevolution rank at the top here: for .25 WSSM with the .257 | 88gr | Osprey Virtus 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.