Load Specifications
Load data in caliber .25 WSSM with .257 | 86gr | Winchester SPRN bullet and 88 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.
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 2015 | <<locked>> | 90% | 56,768 psi | 89% | 3228 fps | 100% |
| Accurate 2200 | <<locked>> | 82% | 56,768 psi | 89% | 3333 fps | 98.3% |
| Accurate 2460 | <<locked>> | 86% | 55,347 psi | 87% | 3251 fps | 100% |
| Accurate 2495 | <<locked>> | 94% | 54,360 psi | 85% | 3241 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 57,087 psi | 89% | 3314 fps | 100% |
| Accurate 4064 | <<locked>> | 98% | 57,696 psi | 90% | 3333 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 46,340 psi | 73% | 3196 fps | 96% |
| Accurate LT-30 | <<locked>> | 84% | 56,275 psi | 88% | 3173 fps | 100% |
| Accurate LT-32 | <<locked>> | 84% | 56,724 psi | 89% | 3199 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 55,869 psi | 88% | 3314 fps | 98.9% |
| ADI AR 2208 | <<locked>> | 98% | 57,116 psi | 90% | 3310 fps | 98.5% |
| ADI AR 2219 | <<locked>> | 84% | 57,348 psi | 90% | 3307 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 55,187 psi | 86% | 3271 fps | 99.5% |
| Alliant AR-Comp | <<locked>> | 90% | 54,984 psi | 86% | 3264 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 56,739 psi | 89% | 3399 fps | 99.4% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 55,434 psi | 87% | 3425 fps | 98.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 98% | 56,086 psi | 88% | 3327 fps | 99.5% |
| Alliant Reloder-10x | <<locked>> | 86% | 56,391 psi | 88% | 3241 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 57,348 psi | 90% | 3360 fps | 98.7% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 46,108 psi | 72% | 3202 fps | 96% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 53,447 psi | 84% | 3386 fps | 99.1% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 55,854 psi | 88% | 3163 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 55,796 psi | 87% | 3320 fps | 98.1% |
| Bofors RP3 | <<locked>> | 98% | 57,029 psi | 89% | 3350 fps | 99.6% |
| Hodgdon Benchmark | <<locked>> | 90% | 57,450 psi | 90% | 3261 fps | 99.9% |
| Hodgdon BL-C2 | <<locked>> | 90% | 54,201 psi | 85% | 3297 fps | 99.7% |
| Hodgdon CFE223 | <<locked>> | 88% | 55,825 psi | 87% | 3399 fps | 98.6% |
| Hodgdon H322 | <<locked>> | 86% | 55,738 psi | 87% | 3284 fps | 100% |
| Hodgdon H335 | <<locked>> | 86% | 57,348 psi | 90% | 3310 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 54,752 psi | 86% | 3294 fps | 97.2% |
| Hodgdon H4895 | <<locked>> | 92% | 56,333 psi | 88% | 3330 fps | 99.3% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 42,250 psi | 66% | 3074 fps | 96.7% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 55,448 psi | 87% | 3360 fps | 99.5% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,592 psi | 54% | 2037 fps | 100% |
| Hodgdon VARGET | <<locked>> | 92% | 54,476 psi | 85% | 3278 fps | 99.1% |
| IMR 3031 | <<locked>> | 92% | 55,550 psi | 87% | 3327 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 56,536 psi | 89% | 3294 fps | 98.6% |
| IMR 4198 | <<locked>> | 86% | 56,739 psi | 89% | 3205 fps | 100% |
| IMR 4895 | <<locked>> | 94% | 54,824 psi | 86% | 3330 fps | 98.9% |
| IMR 8208 XBR | <<locked>> | 90% | 55,187 psi | 86% | 3271 fps | 99.5% |
| Lovex D073.5 | <<locked>> | 86% | 55,332 psi | 87% | 3255 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 92% | 55,158 psi | 86% | 3294 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 56,173 psi | 88% | 3245 fps | 98.9% |
| Lovex S062 | <<locked>> | 96% | 55,970 psi | 88% | 3291 fps | 99.6% |
| Norma 200 | <<locked>> | 82% | 56,347 psi | 88% | 3212 fps | 100% |
| Norma 201 | <<locked>> | 92% | 54,621 psi | 86% | 3261 fps | 99.5% |
| Norma 202 | <<locked>> | 92% | 54,853 psi | 86% | 3271 fps | 100% |
| Norma 203B | <<locked>> | 96% | 56,434 psi | 88% | 3343 fps | 99% |
| Norma URPᴾ | <<locked>> | 100% | 46,340 psi | 73% | 3192 fps | 95.8% |
| Ramshot Big Game | <<locked>> | 96% | 56,884 psi | 89% | 3363 fps | 99% |
| Ramshot TAC | <<locked>> | 90% | 55,912 psi | 88% | 3274 fps | 96.8% |
| Ramshot Wild Boar | <<locked>> | 90% | 54,940 psi | 86% | 3297 fps | 98.8% |
| Ramshot X-Terminator | <<locked>> | 88% | 56,724 psi | 89% | 3271 fps | 98.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,867 psi | 55% | 2083 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 54,752 psi | 86% | 3258 fps | 99.9% |
| ReloadSwiss RS 52 | <<locked>> | 94% | 57,087 psi | 89% | 3425 fps | 98.7% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 57,072 psi | 89% | 3465 fps | 100% |
| Rottweil R 901 | <<locked>> | 90% | 55,405 psi | 87% | 3251 fps | 100% |
| Rottweil R 902 | <<locked>> | 94% | 55,013 psi | 86% | 3255 fps | 99.5% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 56,478 psi | 89% | 3330 fps | 99.4% |
| Shooters World Match Rifle | <<locked>> | 92% | 55,158 psi | 86% | 3294 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 55,970 psi | 88% | 3291 fps | 99.6% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 54,998 psi | 86% | 3225 fps | 99.3% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 56,478 psi | 89% | 2910 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 54,041 psi | 85% | 3255 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 54,708 psi | 86% | 3337 fps | 98.7% |
| SNPE Vectan SP 3 | <<locked>> | 86% | 57,363 psi | 90% | 3268 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 53,940 psi | 85% | 3245 fps | 96.9% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 54,433 psi | 85% | 3281 fps | 98.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 56,681 psi | 89% | 3209 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 56,347 psi | 88% | 3199 fps | 100% |
| Somchem S321 | <<locked>> | 88% | 56,913 psi | 89% | 3314 fps | 99.8% |
| Somchem S335 | <<locked>> | 92% | 55,738 psi | 87% | 3202 fps | 100% |
| Somchem S341 | <<locked>> | 92% | 57,072 psi | 89% | 3301 fps | 99% |
| Somchem S355ᴾ | <<locked>> | 100% | 57,014 psi | 89% | 3330 fps | 99.3% |
| Somchem S365ᴾ | <<locked>> | 100% | 41,104 psi | 64% | 3123 fps | 97.9% |
| Vihtavuori N130 | <<locked>> | 88% | 56,492 psi | 89% | 3182 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 56,536 psi | 89% | 3196 fps | 100% |
| Vihtavuori N135 | <<locked>> | 96% | 57,595 psi | 90% | 3284 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 55,651 psi | 87% | 3248 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 55,288 psi | 87% | 3258 fps | 99.8% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 48,907 psi | 77% | 3199 fps | 96.4% |
| Vihtavuori N530 | <<locked>> | 90% | 55,637 psi | 87% | 3268 fps | 99.6% |
| Vihtavuori N540 | <<locked>> | 96% | 57,421 psi | 90% | 3291 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 48,022 psi | 75% | 3199 fps | 96% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 50,430 psi | 79% | 3186 fps | 98.7% |
| Winchester 748 | <<locked>> | 90% | 54,955 psi | 86% | 3317 fps | 99.9% |
| Winchester StaBALL Match | <<locked>> | 92% | 54,027 psi | 85% | 3287 fps | 99.1% |
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% | 41,423 psi | 65% | 2966 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 53,200 psi | 83% | 3268 fps | 97.7% |
| Accurate 2460 | <<locked>> | 80% | 45,107 psi | 71% | 3071 fps | 99.5% |
| Accurate 2495 | <<locked>> | 80% | 33,997 psi | 53% | 2844 fps | 99.6% |
| Accurate 2520 | <<locked>> | 80% | 40,379 psi | 63% | 3005 fps | 98.6% |
| Accurate 4064 | <<locked>> | 80% | 32,126 psi | 50% | 2815 fps | 97.4% |
| Accurate 4350 | <<locked>> | 98% | 43,207 psi | 68% | 3130 fps | 95.1% |
| Accurate LT-30 | <<locked>> | 80% | 50,009 psi | 78% | 3071 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 50,372 psi | 79% | 3094 fps | 99.8% |
| ADI AR 2206H | <<locked>> | 82% | 40,611 psi | 64% | 3009 fps | 95.7% |
| ADI AR 2208 | <<locked>> | 88% | 41,756 psi | 65% | 3012 fps | 95.2% |
| ADI AR 2219 | <<locked>> | 80% | 50,024 psi | 78% | 3189 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 40,089 psi | 63% | 2972 fps | 97% |
| Alliant AR-Comp | <<locked>> | 80% | 38,986 psi | 61% | 2992 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 46,282 psi | 73% | 3199 fps | 97.8% |
| Alliant Power Pro 2000-MR | 43 gr | 88% | 45,165 psi | 71% | 3212 fps | 95.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 35,868 psi | 56% | 2910 fps | 95.2% |
| Alliant Reloder-10x | <<locked>> | 80% | 46,760 psi | 73% | 3084 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 41,524 psi | 65% | 3048 fps | 95.4% |
| Alliant Reloder-16 | <<locked>> | 98% | 43,366 psi | 68% | 3140 fps | 95% |
| Alliant Reloder-17 | <<locked>> | 90% | 38,116 psi | 60% | 3041 fps | 95.2% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 48,994 psi | 77% | 3054 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 42,627 psi | 67% | 3064 fps | 95% |
| Bofors RP3 | <<locked>> | 84% | 35,418 psi | 56% | 2910 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 42,322 psi | 66% | 2979 fps | 98.1% |
| Hodgdon BL-C2 | <<locked>> | 80% | 38,305 psi | 60% | 2976 fps | 97.1% |
| Hodgdon CFE223 | <<locked>> | 80% | 41,989 psi | 66% | 3120 fps | 95.5% |
| Hodgdon H322 | <<locked>> | 80% | 45,847 psi | 72% | 3110 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 46,514 psi | 73% | 3123 fps | 99.8% |
| Hodgdon H380 | <<locked>> | 92% | 47,761 psi | 75% | 3163 fps | 95.7% |
| Hodgdon H4895 | <<locked>> | 80% | 38,334 psi | 60% | 2963 fps | 95.7% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 39,581 psi | 62% | 3012 fps | 95.9% |
| Hodgdon LEVERevolution | 39.3 gr | 82% | 36,782 psi | 58% | 2969 fps | 95.6% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,643 psi | 40% | 1824 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 36,999 psi | 58% | 2910 fps | 95.1% |
| IMR 3031 | <<locked>> | 80% | 37,304 psi | 58% | 2979 fps | 99.6% |
| IMR 4064 | <<locked>> | 86% | 41,133 psi | 64% | 2992 fps | 95.3% |
| IMR 4198 | <<locked>> | 80% | 47,369 psi | 74% | 3054 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 39,595 psi | 62% | 3018 fps | 95.5% |
| IMR 8208 XBR | <<locked>> | 80% | 40,089 psi | 63% | 2972 fps | 97% |
| Lovex D073.5 | <<locked>> | 80% | 45,078 psi | 71% | 3074 fps | 98.9% |
| Lovex D073.6 | <<locked>> | 80% | 36,419 psi | 57% | 2923 fps | 97.7% |
| Lovex S060 | <<locked>> | 80% | 38,812 psi | 61% | 2894 fps | 95.2% |
| Lovex S062 | <<locked>> | 82% | 35,926 psi | 56% | 2881 fps | 95.8% |
| Norma 200 | <<locked>> | 80% | 52,910 psi | 83% | 3159 fps | 100% |
| Norma 201 | <<locked>> | 80% | 37,362 psi | 59% | 2904 fps | 96.3% |
| Norma 202 | <<locked>> | 80% | 37,362 psi | 59% | 2923 fps | 98.5% |
| Norma 203B | <<locked>> | 86% | 40,814 psi | 64% | 3035 fps | 95.9% |
| Norma URP | <<locked>> | 98% | 43,410 psi | 68% | 3130 fps | 95% |
| Ramshot Big Game | <<locked>> | 86% | 40,379 psi | 63% | 3038 fps | 95.4% |
| Ramshot TAC | <<locked>> | 86% | 49,240 psi | 77% | 3153 fps | 95.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 39,146 psi | 61% | 2976 fps | 95.2% |
| Ramshot X-Terminator | <<locked>> | 80% | 43,642 psi | 68% | 3025 fps | 96.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,715 psi | 40% | 1864 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 44,991 psi | 71% | 3077 fps | 99.1% |
| ReloadSwiss RS 52 | 40.8 gr | 86% | 43,381 psi | 68% | 3163 fps | 95.9% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 33,286 psi | 52% | 2920 fps | 95.8% |
| Rottweil R 901 | <<locked>> | 80% | 41,147 psi | 64% | 2979 fps | 99% |
| Rottweil R 902 | <<locked>> | 80% | 35,563 psi | 56% | 2848 fps | 95.6% |
| Rottweil R 903 | <<locked>> | 88% | 37,739 psi | 59% | 2959 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 36,419 psi | 57% | 2923 fps | 97.7% |
| Shooters World Precision | <<locked>> | 82% | 35,926 psi | 56% | 2881 fps | 95.8% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 47,732 psi | 75% | 3094 fps | 98.3% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 53,432 psi | 84% | 2867 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 50,430 psi | 79% | 3192 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 39,378 psi | 62% | 3022 fps | 95.2% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 47,529 psi | 74% | 3107 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 46,818 psi | 73% | 3110 fps | 95.3% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 39,363 psi | 62% | 2972 fps | 95.3% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 38,957 psi | 61% | 2881 fps | 98.8% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 31,966 psi | 50% | 2717 fps | 98% |
| Somchem S321 | <<locked>> | 80% | 43,134 psi | 68% | 3058 fps | 98% |
| Somchem S335 | <<locked>> | 80% | 38,493 psi | 60% | 2881 fps | 99.2% |
| Somchem S341 | <<locked>> | 82% | 40,538 psi | 64% | 2986 fps | 95.6% |
| Somchem S355 | <<locked>> | 86% | 36,506 psi | 57% | 2913 fps | 95% |
| Somchem S365 | <<locked>> | 94% | 33,953 psi | 53% | 2933 fps | 95.3% |
| Vihtavuori N130 | <<locked>> | 80% | 44,164 psi | 69% | 2979 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 39,044 psi | 61% | 2887 fps | 99.9% |
| Vihtavuori N135 | <<locked>> | 80% | 34,272 psi | 54% | 2851 fps | 99.6% |
| Vihtavuori N140 | <<locked>> | 80% | 35,288 psi | 55% | 2851 fps | 98.3% |
| Vihtavuori N150 | <<locked>> | 84% | 32,489 psi | 51% | 2785 fps | 95.1% |
| Vihtavuori N160 | <<locked>> | 98% | 45,818 psi | 72% | 3136 fps | 95.6% |
| Vihtavuori N530 | <<locked>> | 80% | 40,001 psi | 63% | 2963 fps | 97% |
| Vihtavuori N540 | <<locked>> | 80% | 34,040 psi | 53% | 2828 fps | 97.5% |
| Vihtavuori N550 | <<locked>> | 98% | 44,701 psi | 70% | 3130 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 38,348 psi | 60% | 2927 fps | 95.5% |
| Winchester 748 | <<locked>> | 80% | 38,914 psi | 61% | 3002 fps | 97.6% |
| Winchester StaBALL Match | <<locked>> | 82% | 38,493 psi | 60% | 2969 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 88 powders for .25 WSSM loaded with the .257 | 86gr | Winchester SPRN. ReloadSwiss RS 60 delivers the highest muzzle velocity at 3,465 fps; across all powders the maximum-charge window runs from 2,037 fps to 3,465 fps. Accurate 4350 gives the best case fill at 100 %, and 88 of the 88 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 86.0 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 | 86gr | Winchester SPRN 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.