Load Specifications
Bullet Manufacturer:Winchester
Bullet Weight:100 gr
Bullet Diameter:0.257"
Bullet Length:<<locked>>
Caliber:.25 WSSM load data
Case Length (l3):1.67"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:54.3 Grains of Water
Primer Size:Large Rifle (LR)
Barrel Length:24"
Max. allowed Pressure:63,817 psi
Recommended Twist Rate:1:11.5
Load data in caliber .25 WSSM with .257 | 100gr | Winchester Silvertip bullet and 102 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 60 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.
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>> | 86% | 55,651 psi | 87% | 2995 fps | 100% |
| Accurate 2460 | <<locked>> | 82% | 54,230 psi | 85% | 3022 fps | 100% |
| Accurate 2495 | <<locked>> | 90% | 54,172 psi | 85% | 3018 fps | 100% |
| Accurate 2520 | <<locked>> | 86% | 56,289 psi | 88% | 3087 fps | 100% |
| Accurate 4064 | <<locked>> | 94% | 57,624 psi | 90% | 3114 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 53,780 psi | 84% | 3133 fps | 98.9% |
| Accurate LT-30 | <<locked>> | 82% | 57,740 psi | 90% | 2982 fps | 100% |
| ADI AR 2206H | <<locked>> | 88% | 55,042 psi | 86% | 3097 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 94% | 56,086 psi | 88% | 3094 fps | 99.4% |
| ADI Benchmark 8208 | <<locked>> | 88% | 57,580 psi | 90% | 3100 fps | 100% |
| Alliant AR-Comp | <<locked>> | 86% | 54,578 psi | 86% | 3031 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 82% | 55,593 psi | 87% | 3159 fps | 99.9% |
| Alliant Power Pro 2000-MR | <<locked>> | 90% | 54,534 psi | 85% | 3212 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 94% | 55,637 psi | 87% | 3114 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 82% | 55,376 psi | 87% | 3005 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 92% | 56,376 psi | 88% | 3136 fps | 99.6% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 51,851 psi | 81% | 3136 fps | 98.9% |
| Alliant Reloder-17 | <<locked>> | 98% | 56,840 psi | 89% | 3245 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 36,956 psi | 58% | 2838 fps | 96.8% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 57,464 psi | 90% | 2979 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 88% | 55,013 psi | 86% | 3110 fps | 99.1% |
| Bofors RP3 | <<locked>> | 94% | 56,420 psi | 88% | 3133 fps | 100% |
| Bofors RP7 | <<locked>> | 98% | 56,579 psi | 89% | 3087 fps | 96.4% |
| Hodgdon Benchmark | <<locked>> | 86% | 56,028 psi | 88% | 3035 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 88% | 56,971 psi | 89% | 3133 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 84% | 55,027 psi | 86% | 3176 fps | 99.5% |
| Hodgdon H322 | <<locked>> | 82% | 54,607 psi | 86% | 3048 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 55,709 psi | 87% | 3071 fps | 100% |
| Hodgdon H380 | <<locked>> | 92% | 53,838 psi | 84% | 3084 fps | 98.5% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 56,956 psi | 89% | 3189 fps | 97.2% |
| Hodgdon H4895 | <<locked>> | 88% | 55,564 psi | 87% | 3110 fps | 99.9% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 48,051 psi | 75% | 3005 fps | 99.3% |
| Hodgdon LEVERevolution | <<locked>> | 90% | 54,592 psi | 86% | 3136 fps | 100% |
| Hodgdon Superformance | <<locked>> | 98% | 54,462 psi | 85% | 3166 fps | 96.2% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,273 psi | 55% | 1906 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 56,971 psi | 89% | 3114 fps | 99.9% |
| IMR 3031 | <<locked>> | 88% | 55,100 psi | 86% | 3094 fps | 100% |
| IMR 4064 | <<locked>> | 92% | 55,521 psi | 87% | 3077 fps | 99.5% |
| IMR 4166 Enduron | <<locked>> | 90% | 55,709 psi | 87% | 3051 fps | 96.8% |
| IMR 4198 | <<locked>> | 82% | 55,201 psi | 87% | 2959 fps | 100% |
| IMR 4350ᴾ | <<locked>> | 100% | 53,200 psi | 83% | 3054 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 96% | 55,158 psi | 86% | 3071 fps | 96.6% |
| IMR 4831ᴾ | <<locked>> | 100% | 50,879 psi | 80% | 3068 fps | 98.6% |
| IMR 4895 | <<locked>> | 90% | 54,331 psi | 85% | 3117 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 88% | 57,580 psi | 90% | 3100 fps | 100% |
| Lovex D073.5 | <<locked>> | 82% | 54,317 psi | 85% | 3035 fps | 100% |
| Lovex D073.6 | <<locked>> | 88% | 54,505 psi | 85% | 3071 fps | 100% |
| Lovex S060 | <<locked>> | 88% | 54,766 psi | 86% | 3022 fps | 99.6% |
| Lovex S062 | <<locked>> | 92% | 55,245 psi | 87% | 3074 fps | 100% |
| Lovex S065 | <<locked>> | 98% | 54,418 psi | 85% | 3064 fps | 97.9% |
| Lovex S070ᴾ | <<locked>> | 100% | 55,245 psi | 87% | 3097 fps | 97% |
| Norma 201 | <<locked>> | 90% | 57,174 psi | 90% | 3094 fps | 100% |
| Norma 202 | <<locked>> | 90% | 57,595 psi | 90% | 3097 fps | 100% |
| Norma 203B | <<locked>> | 92% | 55,535 psi | 87% | 3123 fps | 99.7% |
| Norma URPᴾ | <<locked>> | 100% | 52,924 psi | 83% | 3120 fps | 98.7% |
| Ramshot Big Game | <<locked>> | 92% | 56,434 psi | 88% | 3153 fps | 99.7% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 51,938 psi | 81% | 3110 fps | 97.1% |
| Ramshot TAC | <<locked>> | 86% | 54,665 psi | 86% | 3061 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 88% | 57,435 psi | 90% | 3136 fps | 99.8% |
| Ramshot X-Terminator | <<locked>> | 84% | 54,940 psi | 86% | 3045 fps | 99.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,694 psi | 56% | 1949 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 84% | 57,072 psi | 89% | 3084 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 54,360 psi | 85% | 3064 fps | 97.2% |
| ReloadSwiss RS 52 | <<locked>> | 90% | 56,724 psi | 89% | 3209 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 96% | 56,478 psi | 89% | 3245 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 53,490 psi | 84% | 3156 fps | 98.7% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 53,664 psi | 84% | 3182 fps | 98.4% |
| Rottweil R 901 | <<locked>> | 86% | 54,708 psi | 86% | 3028 fps | 100% |
| Rottweil R 902 | <<locked>> | 92% | 57,551 psi | 90% | 3091 fps | 100% |
| Rottweil R 903 | <<locked>> | 96% | 56,260 psi | 88% | 3120 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 98% | 56,579 psi | 89% | 3087 fps | 96.4% |
| Shooters World Long Rifle | <<locked>> | 98% | 54,418 psi | 85% | 3064 fps | 97.9% |
| Shooters World Match Rifle | <<locked>> | 88% | 54,505 psi | 85% | 3071 fps | 100% |
| Shooters World Precision | <<locked>> | 92% | 55,245 psi | 87% | 3074 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 55,245 psi | 87% | 3097 fps | 97% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 56,826 psi | 89% | 3054 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 94% | 54,288 psi | 85% | 3127 fps | 99.6% |
| SNPE Vectan SP 3 | <<locked>> | 82% | 56,347 psi | 88% | 3028 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 88% | 56,420 psi | 88% | 3091 fps | 98.7% |
| SNPE Vectan SP 9 | <<locked>> | 90% | 56,797 psi | 89% | 3117 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 88% | 55,463 psi | 87% | 2986 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 94% | 55,506 psi | 87% | 2979 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 55,027 psi | 86% | 3015 fps | 96.7% |
| Somchem S321 | <<locked>> | 84% | 55,405 psi | 87% | 3084 fps | 100% |
| Somchem S335 | <<locked>> | 88% | 54,679 psi | 86% | 2979 fps | 100% |
| Somchem S341 | <<locked>> | 88% | 56,173 psi | 88% | 3087 fps | 99.7% |
| Somchem S355 | <<locked>> | 96% | 56,550 psi | 89% | 3120 fps | 99.9% |
| Somchem S365ᴾ | <<locked>> | 100% | 47,152 psi | 74% | 3064 fps | 99.9% |
| Vihtavuori N130 | <<locked>> | 84% | 55,303 psi | 87% | 2949 fps | 100% |
| Vihtavuori N133 | <<locked>> | 88% | 55,564 psi | 87% | 2969 fps | 100% |
| Vihtavuori N135 | <<locked>> | 92% | 57,014 psi | 89% | 3054 fps | 100% |
| Vihtavuori N140 | <<locked>> | 90% | 54,897 psi | 86% | 3025 fps | 100% |
| Vihtavuori N150 | <<locked>> | 96% | 54,723 psi | 86% | 3048 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 55,666 psi | 87% | 3120 fps | 99% |
| Vihtavuori N530 | <<locked>> | 86% | 54,549 psi | 85% | 3048 fps | 100% |
| Vihtavuori N540 | <<locked>> | 92% | 56,347 psi | 88% | 3068 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 54,694 psi | 86% | 3127 fps | 98.8% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 39,914 psi | 63% | 2920 fps | 96.8% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 56,579 psi | 89% | 3104 fps | 100% |
| Winchester 748 | <<locked>> | 86% | 54,244 psi | 85% | 3097 fps | 100% |
| Winchester 760ᴾ | <<locked>> | 100% | 56,956 psi | 89% | 3189 fps | 97.2% |
| Winchester StaBALL Match | <<locked>> | 90% | 56,724 psi | 89% | 3127 fps | 99.9% |
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% | 46,282 psi | 73% | 2851 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 50,604 psi | 79% | 2966 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 38,972 psi | 61% | 2759 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 45,788 psi | 72% | 2917 fps | 100% |
| Accurate 4064 | <<locked>> | 80% | 36,825 psi | 58% | 2743 fps | 99.6% |
| Accurate 4350 | <<locked>> | 90% | 37,826 psi | 59% | 2825 fps | 95.3% |
| Accurate LT-30 | <<locked>> | 80% | 54,636 psi | 86% | 2940 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 42,627 psi | 67% | 2867 fps | 98% |
| ADI AR 2208 | <<locked>> | 80% | 36,187 psi | 57% | 2700 fps | 95.4% |
| ADI Benchmark 8208 | <<locked>> | 80% | 44,672 psi | 70% | 2881 fps | 99.2% |
| Alliant AR-Comp | <<locked>> | 80% | 44,556 psi | 70% | 2877 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 52,098 psi | 82% | 3100 fps | 99.7% |
| Alliant Power Pro 2000-MR | 39.1 gr | 80% | 38,624 psi | 61% | 2877 fps | 95.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 35,708 psi | 56% | 2723 fps | 97% |
| Alliant Reloder-10x | <<locked>> | 80% | 51,924 psi | 81% | 2953 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 38,421 psi | 60% | 2789 fps | 96.3% |
| Alliant Reloder-16 | <<locked>> | 90% | 37,956 psi | 59% | 2835 fps | 95.3% |
| Alliant Reloder-17 | 39.5 gr | 82% | 33,069 psi | 52% | 2733 fps | 95.3% |
| Alliant Reloder-23 | <<locked>> | 98% | 34,751 psi | 54% | 2779 fps | 95.9% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 53,867 psi | 84% | 2927 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 41,756 psi | 65% | 2861 fps | 96.7% |
| Bofors RP3 | <<locked>> | 80% | 35,259 psi | 55% | 2723 fps | 97% |
| Bofors RP7 | <<locked>> | 96% | 53,113 psi | 83% | 3031 fps | 95.7% |
| Hodgdon Benchmark | <<locked>> | 80% | 46,673 psi | 73% | 2877 fps | 99.7% |
| Hodgdon BL-C2 | <<locked>> | 80% | 43,352 psi | 68% | 2897 fps | 99.4% |
| Hodgdon CFE223 | <<locked>> | 80% | 47,688 psi | 75% | 3045 fps | 98.5% |
| Hodgdon H322 | <<locked>> | 80% | 51,227 psi | 80% | 2995 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 51,982 psi | 81% | 3015 fps | 100% |
| Hodgdon H380 | <<locked>> | 84% | 41,437 psi | 65% | 2848 fps | 95.8% |
| Hodgdon H414 | <<locked>> | 96% | 49,748 psi | 78% | 3064 fps | 95.7% |
| Hodgdon H4895 | <<locked>> | 80% | 42,975 psi | 67% | 2877 fps | 98.5% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 32,779 psi | 51% | 2667 fps | 95.3% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 38,798 psi | 61% | 2838 fps | 98% |
| Hodgdon Superformance | <<locked>> | 96% | 50,357 psi | 79% | 3091 fps | 95.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,223 psi | 41% | 1703 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 41,336 psi | 65% | 2828 fps | 98.1% |
| IMR 3031 | <<locked>> | 80% | 42,525 psi | 67% | 2884 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 37,971 psi | 60% | 2736 fps | 96.3% |
| IMR 4166 Enduron | <<locked>> | 86% | 49,298 psi | 77% | 2936 fps | 95.4% |
| IMR 4198 | <<locked>> | 80% | 52,141 psi | 82% | 2917 fps | 100% |
| IMR 4350 | <<locked>> | 98% | 49,980 psi | 78% | 2995 fps | 95% |
| IMR 4451 Enduron | <<locked>> | 92% | 48,805 psi | 76% | 2956 fps | 95.2% |
| IMR 4831 | <<locked>> | 92% | 38,943 psi | 61% | 2831 fps | 95.8% |
| IMR 4895 | <<locked>> | 80% | 39,305 psi | 62% | 2825 fps | 97.2% |
| IMR 8208 XBR | <<locked>> | 80% | 44,672 psi | 70% | 2881 fps | 99.2% |
| Lovex D073.5 | <<locked>> | 80% | 50,633 psi | 79% | 2976 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 41,495 psi | 65% | 2844 fps | 99.7% |
| Lovex S060 | <<locked>> | 80% | 42,844 psi | 67% | 2802 fps | 98% |
| Lovex S062 | <<locked>> | 80% | 37,884 psi | 59% | 2746 fps | 98% |
| Lovex S065 | <<locked>> | 90% | 42,511 psi | 67% | 2841 fps | 95.2% |
| Lovex S070 | <<locked>> | 96% | 48,776 psi | 76% | 2982 fps | 95.6% |
| Norma 201 | <<locked>> | 80% | 41,785 psi | 65% | 2818 fps | 98.8% |
| Norma 202 | <<locked>> | 80% | 41,974 psi | 66% | 2831 fps | 99.9% |
| Norma 203B | <<locked>> | 80% | 37,811 psi | 59% | 2779 fps | 96.8% |
| Norma URP | <<locked>> | 90% | 38,247 psi | 60% | 2828 fps | 95.3% |
| Ramshot Big Game | <<locked>> | 80% | 37,289 psi | 58% | 2785 fps | 96.3% |
| Ramshot Hunter | <<locked>> | 96% | 45,527 psi | 71% | 2989 fps | 95.5% |
| Ramshot TAC | <<locked>> | 80% | 44,701 psi | 70% | 2877 fps | 96% |
| Ramshot Wild Boar | <<locked>> | 80% | 43,976 psi | 69% | 2900 fps | 98.2% |
| Ramshot X-Terminator | <<locked>> | 80% | 48,385 psi | 76% | 2933 fps | 98.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,397 psi | 41% | 1742 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 50,038 psi | 78% | 2972 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 44,889 psi | 70% | 2887 fps | 95% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 40,059 psi | 63% | 2894 fps | 96.8% |
| ReloadSwiss RS 60 | 38.5 gr | 80% | 32,822 psi | 51% | 2743 fps | 97.8% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 40,248 psi | 63% | 2900 fps | 95.8% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 43,482 psi | 68% | 2976 fps | 95.9% |
| Rottweil R 901 | <<locked>> | 80% | 45,774 psi | 72% | 2874 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 39,798 psi | 62% | 2766 fps | 98.4% |
| Rottweil R 903 | <<locked>> | 80% | 33,098 psi | 52% | 2661 fps | 95.9% |
| Rottweil R 907 | <<locked>> | 96% | 53,113 psi | 83% | 3031 fps | 95.7% |
| Shooters World Long Rifle | <<locked>> | 90% | 42,511 psi | 67% | 2841 fps | 95.2% |
| Shooters World Match Rifle | <<locked>> | 80% | 41,495 psi | 65% | 2844 fps | 99.7% |
| Shooters World Precision | <<locked>> | 80% | 37,884 psi | 59% | 2746 fps | 98% |
| Shooters World SW4350 | <<locked>> | 96% | 48,776 psi | 76% | 2982 fps | 95.6% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 52,997 psi | 83% | 2992 fps | 99.8% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 34,142 psi | 54% | 2710 fps | 95.2% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 52,837 psi | 83% | 2979 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 42,917 psi | 67% | 2848 fps | 96.1% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 41,176 psi | 65% | 2831 fps | 97.6% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 43,178 psi | 68% | 2779 fps | 99.9% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 35,781 psi | 56% | 2631 fps | 99.7% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 48,008 psi | 75% | 2894 fps | 95.1% |
| Somchem S321 | <<locked>> | 80% | 48,298 psi | 76% | 2963 fps | 99.7% |
| Somchem S335 | <<locked>> | 80% | 42,786 psi | 67% | 2782 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 42,569 psi | 67% | 2848 fps | 97.9% |
| Somchem S355 | <<locked>> | 80% | 34,084 psi | 53% | 2674 fps | 96% |
| Somchem S365 | <<locked>> | 86% | 30,008 psi | 47% | 2651 fps | 95.7% |
| Vihtavuori N130 | <<locked>> | 80% | 48,791 psi | 76% | 2854 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 43,439 psi | 68% | 2776 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 38,972 psi | 61% | 2756 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 39,697 psi | 62% | 2762 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 80% | 32,372 psi | 51% | 2605 fps | 96.9% |
| Vihtavuori N160 | <<locked>> | 90% | 39,943 psi | 63% | 2831 fps | 95.8% |
| Vihtavuori N530 | <<locked>> | 80% | 44,715 psi | 70% | 2874 fps | 99.3% |
| Vihtavuori N540 | <<locked>> | 80% | 38,290 psi | 60% | 2746 fps | 99.6% |
| Vihtavuori N550 | <<locked>> | 90% | 39,291 psi | 62% | 2828 fps | 95.4% |
| Vihtavuori N555 | <<locked>> | 96% | 35,012 psi | 55% | 2802 fps | 95.1% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 33,040 psi | 52% | 2631 fps | 95.6% |
| Winchester 748 | <<locked>> | 80% | 44,121 psi | 69% | 2920 fps | 99.6% |
| Winchester 760 | <<locked>> | 96% | 50,125 psi | 79% | 3071 fps | 95.8% |
| Winchester StaBALL Match | <<locked>> | 80% | 40,538 psi | 64% | 2835 fps | 98% |
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 102 powders for .25 WSSM loaded with the .257 | 100gr | Winchester Silvertip. Alliant Reloder-17 delivers the highest muzzle velocity at 3,245 fps; across all powders the maximum-charge window runs from 1,906 fps to 3,245 fps. Accurate 4350 gives the best case fill at 100 %, and 102 of the 102 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 100.0 gr projectile in 0.257" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder-16, Alliant Reloder-23 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 60, Alliant Reloder-17 rank at the top here: for .25 WSSM with the .257 | 100gr | Winchester Silvertip 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.