Load Specifications
Load data in caliber .25-06 Ackley Improved with .257 | 100gr | Barnes TSX BT bullet and 97 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Reloder-26, Accurate High Country 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 2495 | <<locked>> | 82% | 55,767 psi | 85% | 3071 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 57,479 psi | 88% | 3150 fps | 98.6% |
| Accurate 3100ᴾ | <<locked>> | 100% | 56,478 psi | 87% | 3189 fps | 99.6% |
| Accurate 4064 | <<locked>> | 84% | 56,376 psi | 86% | 3130 fps | 100% |
| Accurate 4350 | <<locked>> | 92% | 58,218 psi | 89% | 3248 fps | 100% |
| Accurate High Country | <<locked>> | 98% | 58,233 psi | 89% | 3346 fps | 97.4% |
| ADI AR 2206H | <<locked>> | 82% | 59,045 psi | 90% | 3222 fps | 100% |
| ADI AR 2208 | <<locked>> | 86% | 56,840 psi | 87% | 3173 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 55,622 psi | 85% | 3232 fps | 97.7% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 57,130 psi | 88% | 3284 fps | 96.9% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 56,463 psi | 87% | 3297 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 55,695 psi | 85% | 3225 fps | 97.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 57,740 psi | 88% | 3196 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 84% | 57,870 psi | 89% | 3222 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 94% | 59,030 psi | 90% | 3314 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 56,826 psi | 87% | 3278 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 98% | 58,958 psi | 90% | 3281 fps | 98.4% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 56,246 psi | 86% | 3278 fps | 98.1% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 53,011 psi | 81% | 3202 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 45,919 psi | 70% | 3114 fps | 98.9% |
| Alliant Reloder-26 | <<locked>> | 98% | 57,740 psi | 88% | 3356 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 51,416 psi | 79% | 3189 fps | 97% |
| Bofors RP3 | <<locked>> | 86% | 58,726 psi | 90% | 3212 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 56,246 psi | 86% | 3278 fps | 98.1% |
| Bofors RP7 | <<locked>> | 90% | 58,117 psi | 89% | 3199 fps | 98.9% |
| Hodgdon H380 | <<locked>> | 84% | 55,245 psi | 85% | 3169 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 90% | 56,666 psi | 87% | 3245 fps | 99.1% |
| Hodgdon H4350 | <<locked>> | 88% | 56,028 psi | 86% | 3199 fps | 98.1% |
| Hodgdon H4831 | <<locked>> | 98% | 57,421 psi | 88% | 3225 fps | 96.2% |
| Hodgdon H4831 SC | <<locked>> | 98% | 56,115 psi | 86% | 3205 fps | 96% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 55,448 psi | 85% | 3169 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 56,710 psi | 87% | 3209 fps | 100% |
| Hodgdon Superformance | <<locked>> | 90% | 57,392 psi | 88% | 3281 fps | 99.1% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,303 psi | 56% | 2041 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 57,058 psi | 87% | 3176 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 56,115 psi | 86% | 3153 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 58,842 psi | 90% | 3192 fps | 99.3% |
| IMR 4350 | <<locked>> | 92% | 55,753 psi | 85% | 3173 fps | 98.6% |
| IMR 4451 Enduron | <<locked>> | 88% | 56,101 psi | 86% | 3169 fps | 98.9% |
| IMR 4831 | <<locked>> | 94% | 58,494 psi | 90% | 3235 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 55,680 psi | 85% | 3192 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 98% | 58,552 psi | 90% | 3212 fps | 96.7% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 54,433 psi | 83% | 3248 fps | 96.4% |
| Lovex S060 | <<locked>> | 82% | 57,435 psi | 88% | 3136 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 56,202 psi | 86% | 3143 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 56,260 psi | 86% | 3163 fps | 99.7% |
| Lovex S070 | <<locked>> | 92% | 57,783 psi | 89% | 3205 fps | 99.3% |
| Lovex S071ᴾ | <<locked>> | 100% | 46,572 psi | 71% | 3018 fps | 98.2% |
| Norma 201 | <<locked>> | 82% | 57,406 psi | 88% | 3156 fps | 100% |
| Norma 202 | <<locked>> | 82% | 58,436 psi | 90% | 3156 fps | 100% |
| Norma 203B | <<locked>> | 84% | 57,116 psi | 88% | 3205 fps | 100% |
| Norma 204 | <<locked>> | 92% | 56,724 psi | 87% | 3225 fps | 97.8% |
| Norma MRP | <<locked>> | 98% | 56,318 psi | 86% | 3307 fps | 99.1% |
| Norma URP | <<locked>> | 92% | 56,797 psi | 87% | 3232 fps | 100% |
| Ramshot Big Game | <<locked>> | 84% | 58,305 psi | 89% | 3228 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 55,201 psi | 85% | 3271 fps | 97% |
| Ramshot Hunter | <<locked>> | 92% | 55,651 psi | 85% | 3225 fps | 99.5% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 49,501 psi | 76% | 3130 fps | 97.5% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,941 psi | 57% | 2087 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 59,001 psi | 90% | 3212 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 56,115 psi | 86% | 3271 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 58,494 psi | 90% | 3271 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 57,174 psi | 88% | 3307 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 45,295 psi | 69% | 3140 fps | 97.4% |
| Rottweil R 902 | <<locked>> | 84% | 58,233 psi | 89% | 3159 fps | 100% |
| Rottweil R 903 | <<locked>> | 88% | 58,929 psi | 90% | 3209 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 57,246 psi | 88% | 3202 fps | 97% |
| Rottweil R 905 | <<locked>> | 98% | 58,059 psi | 89% | 3264 fps | 98.3% |
| Rottweil R 907 | <<locked>> | 90% | 58,117 psi | 89% | 3199 fps | 98.9% |
| Shooters World Long Rifle | <<locked>> | 90% | 56,260 psi | 86% | 3163 fps | 99.7% |
| Shooters World Precision | <<locked>> | 84% | 56,202 psi | 86% | 3143 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 57,783 psi | 89% | 3205 fps | 99.3% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 56,811 psi | 87% | 3212 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 57,551 psi | 88% | 3186 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 82% | 58,291 psi | 89% | 3087 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 55,985 psi | 86% | 3038 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 55,999 psi | 86% | 3110 fps | 99% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 57,566 psi | 88% | 3261 fps | 98.2% |
| Somchem S335 | <<locked>> | 82% | 57,899 psi | 89% | 3077 fps | 100% |
| Somchem S355 | <<locked>> | 88% | 58,653 psi | 90% | 3202 fps | 100% |
| Somchem S365 | <<locked>> | 94% | 56,420 psi | 86% | 3232 fps | 100% |
| Somchem S385 | <<locked>> | 98% | 58,668 psi | 90% | 3235 fps | 99% |
| Vihtavuori N133 | <<locked>> | 82% | 58,856 psi | 90% | 3068 fps | 100% |
| Vihtavuori N135 | <<locked>> | 84% | 58,595 psi | 90% | 3114 fps | 100% |
| Vihtavuori N140 | <<locked>> | 84% | 58,958 psi | 90% | 3127 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 56,536 psi | 87% | 3120 fps | 100% |
| Vihtavuori N160 | <<locked>> | 92% | 59,016 psi | 90% | 3228 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 54,447 psi | 83% | 3150 fps | 98.1% |
| Vihtavuori N540 | <<locked>> | 84% | 57,276 psi | 88% | 3123 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 58,030 psi | 89% | 3228 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 55,506 psi | 85% | 3232 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 56,420 psi | 86% | 3297 fps | 96.4% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 54,955 psi | 84% | 3127 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 56,942 psi | 87% | 3248 fps | 99.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 49,052 psi | 75% | 3268 fps | 100% |
| Winchester StaBALL Match | <<locked>> | 82% | 57,957 psi | 89% | 3196 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 55,143 psi | 84% | 3169 fps | 97.7% |
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 2495 | <<locked>> | 80% | 52,156 psi | 80% | 3018 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 50,328 psi | 77% | 3025 fps | 97.4% |
| Accurate 3100 | <<locked>> | 88% | 36,637 psi | 56% | 2802 fps | 95.4% |
| Accurate 4064 | <<locked>> | 80% | 49,429 psi | 76% | 3025 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 37,942 psi | 58% | 2861 fps | 97.5% |
| Accurate High Country | 59.9 gr | 94% | 50,169 psi | 77% | 3199 fps | 95.6% |
| ADI AR 2206H | <<locked>> | 80% | 55,405 psi | 85% | 3166 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 46,862 psi | 72% | 2995 fps | 99.6% |
| ADI AR 2209 | <<locked>> | 90% | 45,440 psi | 70% | 3038 fps | 95.2% |
| ADI AR 2213 | <<locked>> | 96% | 49,864 psi | 76% | 3150 fps | 95% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 52,402 psi | 80% | 3228 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 90% | 45,614 psi | 70% | 3035 fps | 95.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 47,543 psi | 73% | 3025 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 50,836 psi | 78% | 3104 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 80% | 36,970 psi | 57% | 2877 fps | 97.6% |
| Alliant Reloder-17 | 51.2 gr | 80% | 42,148 psi | 65% | 3015 fps | 99.7% |
| Alliant Reloder-19 | <<locked>> | 90% | 45,078 psi | 69% | 3025 fps | 95.2% |
| Alliant Reloder-22 | <<locked>> | 94% | 45,571 psi | 70% | 3077 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 82% | 28,761 psi | 44% | 2651 fps | 95.7% |
| Alliant Reloder-25 | <<locked>> | 92% | 35,230 psi | 54% | 2851 fps | 95.4% |
| Alliant Reloder-26 | 55.1 gr | 84% | 33,475 psi | 51% | 2838 fps | 95.4% |
| Bofors RP15 | <<locked>> | 96% | 44,933 psi | 69% | 3058 fps | 95.2% |
| Bofors RP3 | <<locked>> | 80% | 47,848 psi | 73% | 3035 fps | 100% |
| Bofors RP5 | <<locked>> | 94% | 45,571 psi | 70% | 3077 fps | 95.6% |
| Bofors RP7 | <<locked>> | 80% | 42,003 psi | 64% | 2890 fps | 95.4% |
| Hodgdon H380 | <<locked>> | 80% | 48,167 psi | 74% | 3041 fps | 99.2% |
| Hodgdon H414 | <<locked>> | 80% | 39,972 psi | 61% | 2913 fps | 95.4% |
| Hodgdon H4350 | <<locked>> | 82% | 45,934 psi | 70% | 3009 fps | 95.8% |
| Hodgdon H4831 | <<locked>> | 96% | 53,592 psi | 82% | 3163 fps | 95.4% |
| Hodgdon H4831 SC | <<locked>> | 96% | 52,388 psi | 80% | 3140 fps | 95% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 34,476 psi | 53% | 2759 fps | 98.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 52,852 psi | 81% | 3150 fps | 100% |
| Hodgdon Superformance | <<locked>> | 82% | 42,250 psi | 65% | 2992 fps | 95.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,093 psi | 42% | 1831 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 53,505 psi | 82% | 3120 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 49,284 psi | 76% | 3035 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 80% | 51,590 psi | 79% | 3068 fps | 98.3% |
| IMR 4350 | <<locked>> | 84% | 42,888 psi | 66% | 2923 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 80% | 43,526 psi | 67% | 2927 fps | 96.4% |
| IMR 4831 | <<locked>> | 80% | 36,332 psi | 56% | 2808 fps | 97.1% |
| IMR 4895 | <<locked>> | 80% | 52,156 psi | 80% | 3133 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 51,576 psi | 79% | 3091 fps | 95.1% |
| IMR 7828 SSC | <<locked>> | 98% | 50,821 psi | 78% | 3182 fps | 95.4% |
| Lovex S060 | <<locked>> | 80% | 53,925 psi | 83% | 3084 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 49,400 psi | 76% | 3031 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 40,799 psi | 63% | 2864 fps | 97.1% |
| Lovex S070 | <<locked>> | 80% | 38,957 psi | 60% | 2838 fps | 95.3% |
| Lovex S071 | <<locked>> | 94% | 37,956 psi | 58% | 2835 fps | 95.9% |
| Norma 201 | <<locked>> | 80% | 53,838 psi | 82% | 3100 fps | 100% |
| Norma 202 | <<locked>> | 80% | 54,766 psi | 84% | 3100 fps | 100% |
| Norma 203B | <<locked>> | 80% | 50,183 psi | 77% | 3087 fps | 100% |
| Norma 204 | <<locked>> | 86% | 45,876 psi | 70% | 3022 fps | 95.2% |
| Norma MRP | <<locked>> | 90% | 41,945 psi | 64% | 3025 fps | 96% |
| Norma URP | <<locked>> | 80% | 37,681 psi | 58% | 2858 fps | 97.3% |
| Ramshot Big Game | <<locked>> | 80% | 50,662 psi | 78% | 3104 fps | 100% |
| Ramshot Grand | <<locked>> | 98% | 51,082 psi | 78% | 3196 fps | 95.9% |
| Ramshot Hunter | <<locked>> | 80% | 36,825 psi | 56% | 2841 fps | 95.2% |
| Ramshot Magnum | <<locked>> | 96% | 42,366 psi | 65% | 2982 fps | 95.4% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,514 psi | 42% | 1873 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 48,225 psi | 74% | 3025 fps | 98.2% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 44,860 psi | 69% | 3077 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 37,855 psi | 58% | 2874 fps | 97.2% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 36,680 psi | 56% | 2881 fps | 96.4% |
| ReloadSwiss RS 76 | <<locked>> | 98% | 42,061 psi | 64% | 3058 fps | 96.2% |
| Rottweil R 902 | <<locked>> | 80% | 51,169 psi | 78% | 3048 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 44,802 psi | 69% | 2972 fps | 99.9% |
| Rottweil R 904 | <<locked>> | 92% | 50,154 psi | 77% | 3077 fps | 95.3% |
| Rottweil R 905 | <<locked>> | 90% | 43,918 psi | 67% | 3002 fps | 95.1% |
| Rottweil R 907 | <<locked>> | 80% | 42,003 psi | 64% | 2890 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 40,799 psi | 63% | 2864 fps | 97.1% |
| Shooters World Precision | <<locked>> | 80% | 49,400 psi | 76% | 3031 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 38,957 psi | 60% | 2838 fps | 95.3% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 46,514 psi | 71% | 3035 fps | 99.8% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 54,027 psi | 83% | 3130 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 54,563 psi | 84% | 3035 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 46,180 psi | 71% | 2884 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,059 psi | 61% | 2805 fps | 95.6% |
| SNPE Vectan Tubal 8000 | <<locked>> | 92% | 46,905 psi | 72% | 3064 fps | 95.9% |
| Somchem S335 | <<locked>> | 80% | 54,389 psi | 83% | 3028 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 45,194 psi | 69% | 2972 fps | 99.8% |
| Somchem S365 | <<locked>> | 80% | 34,185 psi | 52% | 2805 fps | 99.2% |
| Somchem S385 | <<locked>> | 88% | 41,669 psi | 64% | 2917 fps | 95.3% |
| Vihtavuori N133 | <<locked>> | 80% | 55,187 psi | 85% | 3018 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 51,561 psi | 79% | 3012 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 51,837 psi | 79% | 3025 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 43,163 psi | 66% | 2894 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 39,291 psi | 60% | 2861 fps | 97.8% |
| Vihtavuori N165 | <<locked>> | 94% | 44,179 psi | 68% | 2959 fps | 95.7% |
| Vihtavuori N540 | <<locked>> | 80% | 50,183 psi | 77% | 3015 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 38,624 psi | 59% | 2858 fps | 97.4% |
| Vihtavuori N555 | <<locked>> | 82% | 31,850 psi | 49% | 2733 fps | 95.9% |
| Vihtavuori N560 | <<locked>> | 96% | 52,431 psi | 80% | 3225 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 38,580 psi | 59% | 2828 fps | 99.4% |
| Winchester 760 | <<locked>> | 80% | 40,190 psi | 62% | 2917 fps | 95.4% |
| Winchester StaBALL HD | <<locked>> | 84% | 27,224 psi | 42% | 2674 fps | 95.5% |
| Winchester StaBALL Match | <<locked>> | 80% | 54,070 psi | 83% | 3136 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 44,469 psi | 68% | 2972 fps | 95% |
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 97 powders for .25-06 Ackley Improved loaded with the .257 | 100gr | Barnes TSX BT. Alliant Reloder-26 delivers the highest muzzle velocity at 3,356 fps; across all powders the maximum-charge window runs from 2,041 fps to 3,356 fps. Accurate 3100 gives the best case fill at 100 %, and 97 of the 97 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (450 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 100.0 gr projectile in 0.257" calls for a 1:10.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2213, Alliant Reloder-22 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 Reloder-26, Accurate High Country, Alliant Reloder-17 rank at the top here: for .25-06 Ackley Improved with the .257 | 100gr | Barnes TSX BT 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.