Load Specifications
Load data in caliber .25 WSSM with .257 | 80gr | Impala LW CFN bullet and 82 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 ReloadSwiss RS 60.
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>> | 88% | 55,259 psi | 87% | 3297 fps | 100% |
| Accurate 2460 | <<locked>> | 86% | 57,667 psi | 90% | 3373 fps | 100% |
| Accurate 2495 | <<locked>> | 94% | 57,696 psi | 90% | 3376 fps | 100% |
| Accurate 2520 | <<locked>> | 88% | 55,637 psi | 87% | 3379 fps | 99.9% |
| Accurate 4064 | <<locked>> | 96% | 56,942 psi | 89% | 3409 fps | 100% |
| Accurate LT-30 | <<locked>> | 84% | 57,334 psi | 90% | 3284 fps | 100% |
| Accurate LT-32 | <<locked>> | 84% | 57,711 psi | 90% | 3310 fps | 100% |
| ADI AR 2206H | <<locked>> | 92% | 57,522 psi | 90% | 3432 fps | 98.7% |
| ADI AR 2208 | <<locked>> | 96% | 54,650 psi | 86% | 3353 fps | 97.6% |
| ADI AR 2219 | <<locked>> | 82% | 55,042 psi | 86% | 3366 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 90% | 56,739 psi | 89% | 3386 fps | 99.3% |
| Alliant AR-Comp | <<locked>> | 90% | 56,362 psi | 88% | 3383 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 84% | 54,752 psi | 86% | 3451 fps | 98.7% |
| Alliant Power Pro 2000-MR | <<locked>> | 94% | 56,927 psi | 89% | 3540 fps | 97.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 96% | 54,302 psi | 85% | 3386 fps | 98.9% |
| Alliant Reloder-10x | <<locked>> | 84% | 54,752 psi | 86% | 3314 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 94% | 55,100 psi | 86% | 3409 fps | 97.9% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 54,926 psi | 86% | 3497 fps | 98.8% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 56,724 psi | 89% | 3268 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 92% | 57,305 psi | 90% | 3435 fps | 97.7% |
| Bofors RP3 | <<locked>> | 96% | 55,405 psi | 87% | 3409 fps | 99.1% |
| Hodgdon Benchmark | <<locked>> | 88% | 55,376 psi | 87% | 3317 fps | 99.5% |
| Hodgdon BL-C2 | <<locked>> | 90% | 55,927 psi | 88% | 3415 fps | 99.6% |
| Hodgdon CFE223 | <<locked>> | 88% | 57,029 psi | 89% | 3510 fps | 98.2% |
| Hodgdon H322 | <<locked>> | 86% | 56,985 psi | 89% | 3396 fps | 100% |
| Hodgdon H335 | <<locked>> | 84% | 54,810 psi | 86% | 3363 fps | 100% |
| Hodgdon H380 | <<locked>> | 96% | 56,434 psi | 88% | 3406 fps | 96.9% |
| Hodgdon H4895 | <<locked>> | 90% | 54,708 psi | 86% | 3389 fps | 98.7% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 43,918 psi | 69% | 3186 fps | 96.4% |
| Hodgdon LEVERevolution | <<locked>> | 94% | 56,579 psi | 89% | 3468 fps | 99.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,824 psi | 55% | 2113 fps | 100% |
| Hodgdon VARGET | <<locked>> | 92% | 55,840 psi | 88% | 3389 fps | 98.8% |
| IMR 3031 | <<locked>> | 92% | 56,811 psi | 89% | 3442 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 57,479 psi | 90% | 3396 fps | 98.3% |
| IMR 4198 | <<locked>> | 86% | 57,479 psi | 90% | 3317 fps | 100% |
| IMR 4895 | <<locked>> | 94% | 56,420 psi | 88% | 3448 fps | 98.6% |
| IMR 8208 XBR | <<locked>> | 90% | 56,739 psi | 89% | 3386 fps | 99.3% |
| Lovex D073.5 | <<locked>> | 86% | 57,638 psi | 90% | 3379 fps | 99.8% |
| Lovex D073.6 | <<locked>> | 92% | 57,217 psi | 90% | 3415 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 57,217 psi | 90% | 3350 fps | 98.6% |
| Lovex S062 | <<locked>> | 96% | 57,363 psi | 90% | 3402 fps | 99.5% |
| Norma 201 | <<locked>> | 92% | 56,855 psi | 89% | 3383 fps | 99.4% |
| Norma 202 | <<locked>> | 92% | 56,637 psi | 89% | 3389 fps | 100% |
| Norma 203B | <<locked>> | 94% | 54,244 psi | 85% | 3392 fps | 98.2% |
| Ramshot Big Game | <<locked>> | 94% | 54,621 psi | 86% | 3412 fps | 98.1% |
| Ramshot TAC | <<locked>> | 90% | 57,566 psi | 90% | 3386 fps | 96.4% |
| Ramshot Wild Boar | <<locked>> | 90% | 56,333 psi | 88% | 3409 fps | 98.5% |
| Ramshot X-Terminator | <<locked>> | 86% | 54,607 psi | 86% | 3320 fps | 98.1% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,505 psi | 56% | 2169 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 86% | 56,376 psi | 88% | 3376 fps | 99.9% |
| ReloadSwiss RS 52 | <<locked>> | 92% | 54,694 psi | 86% | 3478 fps | 97.8% |
| ReloadSwiss RS 60 | <<locked>> | 98% | 54,708 psi | 86% | 3514 fps | 100% |
| Rottweil R 901 | <<locked>> | 88% | 55,042 psi | 86% | 3330 fps | 99.9% |
| Rottweil R 902 | <<locked>> | 94% | 57,130 psi | 90% | 3379 fps | 99.4% |
| Rottweil R 903 | <<locked>> | 98% | 54,897 psi | 86% | 3392 fps | 98.8% |
| Shooters World Match Rifle | <<locked>> | 92% | 57,217 psi | 90% | 3415 fps | 100% |
| Shooters World Precision | <<locked>> | 96% | 57,363 psi | 90% | 3402 fps | 99.5% |
| Shooters World Tactical Rifle | <<locked>> | 84% | 56,202 psi | 88% | 3333 fps | 99.1% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 57,276 psi | 90% | 3015 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 82% | 55,419 psi | 87% | 3369 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 98% | 56,202 psi | 88% | 3448 fps | 98.5% |
| SNPE Vectan SP 3 | <<locked>> | 84% | 55,187 psi | 86% | 3330 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 90% | 55,666 psi | 87% | 3356 fps | 96.6% |
| SNPE Vectan SP 9 | <<locked>> | 92% | 55,825 psi | 87% | 3392 fps | 98.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 90% | 54,940 psi | 86% | 3271 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 57,740 psi | 90% | 3310 fps | 100% |
| Somchem S321 | <<locked>> | 86% | 54,578 psi | 86% | 3363 fps | 99.3% |
| Somchem S335 | <<locked>> | 92% | 57,653 psi | 90% | 3323 fps | 100% |
| Somchem S341 | <<locked>> | 90% | 54,984 psi | 86% | 3353 fps | 98.2% |
| Somchem S355 | <<locked>> | 98% | 55,274 psi | 87% | 3389 fps | 98.7% |
| Somchem S365ᴾ | <<locked>> | 100% | 43,105 psi | 68% | 3245 fps | 97.8% |
| Vihtavuori N130 | <<locked>> | 86% | 54,636 psi | 86% | 3248 fps | 100% |
| Vihtavuori N133 | <<locked>> | 90% | 54,694 psi | 86% | 3261 fps | 100% |
| Vihtavuori N135 | <<locked>> | 94% | 55,492 psi | 87% | 3346 fps | 100% |
| Vihtavuori N140 | <<locked>> | 94% | 57,203 psi | 90% | 3363 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 56,768 psi | 89% | 3369 fps | 99.6% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 50,241 psi | 79% | 3304 fps | 95.9% |
| Vihtavuori N530 | <<locked>> | 90% | 57,232 psi | 90% | 3386 fps | 99.4% |
| Vihtavuori N540 | <<locked>> | 94% | 55,477 psi | 87% | 3350 fps | 100% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 51,822 psi | 81% | 3291 fps | 98.4% |
| Winchester 748 | <<locked>> | 90% | 56,362 psi | 88% | 3435 fps | 99.8% |
| Winchester StaBALL Match | <<locked>> | 92% | 55,434 psi | 87% | 3399 fps | 98.8% |
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% | 43,816 psi | 69% | 3094 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 47,747 psi | 75% | 3199 fps | 99.5% |
| Accurate 2495 | <<locked>> | 80% | 37,434 psi | 59% | 2995 fps | 99.8% |
| Accurate 2520 | <<locked>> | 80% | 42,583 psi | 67% | 3130 fps | 98.6% |
| Accurate 4064 | <<locked>> | 80% | 35,331 psi | 55% | 2966 fps | 97.8% |
| Accurate LT-30 | <<locked>> | 80% | 50,966 psi | 80% | 3176 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 51,300 psi | 80% | 3199 fps | 99.6% |
| ADI AR 2206H | <<locked>> | 82% | 42,453 psi | 67% | 3127 fps | 95.5% |
| ADI AR 2208 | <<locked>> | 90% | 45,847 psi | 72% | 3179 fps | 95.7% |
| ADI AR 2219 | <<locked>> | 80% | 51,416 psi | 81% | 3304 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 41,829 psi | 66% | 3087 fps | 96.7% |
| Alliant AR-Comp | <<locked>> | 80% | 40,901 psi | 64% | 3117 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 48,051 psi | 75% | 3317 fps | 97.6% |
| Alliant Power Pro 2000-MR | 43.8 gr | 88% | 46,702 psi | 73% | 3323 fps | 95.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 37,811 psi | 59% | 3031 fps | 95.1% |
| Alliant Reloder-10x | <<locked>> | 80% | 48,892 psi | 77% | 3212 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 43,279 psi | 68% | 3166 fps | 95.1% |
| Alliant Reloder-17 | <<locked>> | 92% | 42,540 psi | 67% | 3225 fps | 95.9% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 50,169 psi | 79% | 3163 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 46,905 psi | 74% | 3238 fps | 95.5% |
| Bofors RP3 | <<locked>> | 84% | 37,724 psi | 59% | 3038 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 43,743 psi | 69% | 3087 fps | 97.8% |
| Hodgdon BL-C2 | <<locked>> | 80% | 40,292 psi | 63% | 3100 fps | 97% |
| Hodgdon CFE223 | <<locked>> | 80% | 43,714 psi | 69% | 3238 fps | 95.2% |
| Hodgdon H322 | <<locked>> | 80% | 47,094 psi | 74% | 3222 fps | 99.9% |
| Hodgdon H335 | <<locked>> | 80% | 48,080 psi | 75% | 3241 fps | 99.7% |
| Hodgdon H380 | <<locked>> | 92% | 49,705 psi | 78% | 3281 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 40,335 psi | 63% | 3084 fps | 95.5% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 41,307 psi | 65% | 3123 fps | 95.6% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 38,450 psi | 60% | 3087 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,136 psi | 41% | 1896 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 41,017 psi | 64% | 3084 fps | 95.7% |
| IMR 3031 | <<locked>> | 80% | 38,957 psi | 61% | 3100 fps | 99.5% |
| IMR 4064 | <<locked>> | 86% | 42,772 psi | 67% | 3104 fps | 95% |
| IMR 4198 | <<locked>> | 80% | 48,515 psi | 76% | 3169 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 41,756 psi | 65% | 3146 fps | 95.4% |
| IMR 8208 XBR | <<locked>> | 80% | 41,829 psi | 66% | 3087 fps | 96.7% |
| Lovex D073.5 | <<locked>> | 80% | 47,413 psi | 74% | 3196 fps | 98.8% |
| Lovex D073.6 | <<locked>> | 80% | 38,769 psi | 61% | 3051 fps | 97.7% |
| Lovex S060 | <<locked>> | 80% | 40,553 psi | 64% | 3009 fps | 95% |
| Lovex S062 | <<locked>> | 80% | 35,940 psi | 56% | 2946 fps | 95% |
| Norma 201 | <<locked>> | 80% | 39,784 psi | 62% | 3035 fps | 96.3% |
| Norma 202 | <<locked>> | 80% | 39,407 psi | 62% | 3048 fps | 98.4% |
| Norma 203B | <<locked>> | 86% | 42,670 psi | 67% | 3153 fps | 95.6% |
| Ramshot Big Game | <<locked>> | 86% | 42,105 psi | 66% | 3156 fps | 95.1% |
| Ramshot TAC | <<locked>> | 88% | 53,751 psi | 84% | 3317 fps | 95.6% |
| Ramshot Wild Boar | <<locked>> | 82% | 43,497 psi | 68% | 3153 fps | 95.8% |
| Ramshot X-Terminator | <<locked>> | 80% | 45,252 psi | 71% | 3136 fps | 96.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,295 psi | 41% | 1939 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 46,630 psi | 73% | 3196 fps | 98.9% |
| ReloadSwiss RS 52 | 41.5 gr | 86% | 44,860 psi | 70% | 3278 fps | 95.5% |
| ReloadSwiss RS 60 | 41.2 gr | 84% | 35,201 psi | 55% | 3041 fps | 95.7% |
| Rottweil R 901 | <<locked>> | 80% | 43,729 psi | 69% | 3107 fps | 99% |
| Rottweil R 902 | <<locked>> | 80% | 37,826 psi | 59% | 2972 fps | 95.6% |
| Rottweil R 903 | <<locked>> | 88% | 40,234 psi | 63% | 3091 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 38,769 psi | 61% | 3051 fps | 97.7% |
| Shooters World Precision | <<locked>> | 80% | 35,940 psi | 56% | 2946 fps | 95% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 49,269 psi | 77% | 3205 fps | 98.1% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 54,737 psi | 86% | 2979 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 51,909 psi | 81% | 3307 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 43,627 psi | 68% | 3199 fps | 95.7% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 49,110 psi | 77% | 3225 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 48,805 psi | 76% | 3228 fps | 95% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 41,002 psi | 64% | 3087 fps | 95% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 40,959 psi | 64% | 3002 fps | 98.7% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 33,852 psi | 53% | 2838 fps | 98% |
| Somchem S321 | <<locked>> | 80% | 44,933 psi | 70% | 3176 fps | 97.8% |
| Somchem S335 | <<locked>> | 80% | 40,640 psi | 64% | 3005 fps | 99.2% |
| Somchem S341 | <<locked>> | 82% | 42,076 psi | 66% | 3097 fps | 95.3% |
| Somchem S355 | <<locked>> | 88% | 40,930 psi | 64% | 3097 fps | 95.7% |
| Somchem S365 | <<locked>> | 94% | 35,940 psi | 56% | 3054 fps | 95.2% |
| Vihtavuori N130 | <<locked>> | 80% | 46,079 psi | 72% | 3100 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 40,814 psi | 64% | 3005 fps | 99.9% |
| Vihtavuori N135 | <<locked>> | 80% | 36,535 psi | 57% | 2979 fps | 99.6% |
| Vihtavuori N140 | <<locked>> | 80% | 37,231 psi | 58% | 2969 fps | 98.2% |
| Vihtavuori N150 | <<locked>> | 84% | 34,505 psi | 54% | 2904 fps | 95.1% |
| Vihtavuori N160 | <<locked>> | 98% | 47,340 psi | 74% | 3245 fps | 95.1% |
| Vihtavuori N530 | <<locked>> | 80% | 41,829 psi | 66% | 3081 fps | 96.8% |
| Vihtavuori N540 | <<locked>> | 80% | 35,998 psi | 56% | 2949 fps | 97.4% |
| Winchester 6.5 StaBALL | <<locked>> | 92% | 40,176 psi | 63% | 3038 fps | 95.3% |
| Winchester 748 | <<locked>> | 80% | 40,596 psi | 64% | 3120 fps | 97.4% |
| Winchester StaBALL Match | <<locked>> | 82% | 40,190 psi | 63% | 3084 fps | 95.5% |
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 82 powders for .25 WSSM loaded with the .257 | 80gr | Impala LW CFN. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,540 fps; across all powders the maximum-charge window runs from 2,113 fps to 3,540 fps. Alliant Reloder-17 gives the best case fill at 100 %, and 82 of the 82 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 55–90 %, leaving at least 10 % headroom. The 80.0 gr projectile in 0.257" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. Alliant Reloder-17, Hodgdon Hybrid 100V, 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 Power Pro 2000-MR, ReloadSwiss RS 52, ReloadSwiss RS 60 rank at the top here: for .25 WSSM with the .257 | 80gr | Impala LW CFN 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.