Load Specifications
Load data in caliber .25 Creedmoor with .257 | 120gr | Speer Boat-Tail bullet and 98 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Alliant Reloder-17 and Hodgdon Superformance.
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>> | 82% | 54,578 psi | 88% | 2684 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 53,272 psi | 86% | 2707 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 54,679 psi | 88% | 2769 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 55,825 psi | 90% | 2766 fps | 97.7% |
| Accurate 3100ᴾ | <<locked>> | 100% | 43,888 psi | 71% | 2671 fps | 97.2% |
| Accurate 4064 | <<locked>> | 88% | 53,635 psi | 87% | 2759 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 53,447 psi | 86% | 2844 fps | 99.7% |
| ADI AR 2206H | <<locked>> | 84% | 53,621 psi | 86% | 2789 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 54,462 psi | 88% | 2785 fps | 99.9% |
| ADI AR 2209ᴾ | <<locked>> | 100% | 51,677 psi | 83% | 2822 fps | 96.1% |
| ADI Benchmark 8208 | <<locked>> | 84% | 55,970 psi | 90% | 2785 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 53,272 psi | 86% | 2707 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 53,243 psi | 86% | 2904 fps | 99.9% |
| Alliant Power Pro Varmintᴾ | <<locked>> | 100% | 51,242 psi | 83% | 2815 fps | 96.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 54,592 psi | 88% | 2808 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 55,230 psi | 89% | 2831 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 98% | 54,273 psi | 88% | 2897 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 94% | 55,695 psi | 90% | 2936 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 50,517 psi | 81% | 2808 fps | 96% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 41,481 psi | 67% | 2694 fps | 99.5% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 46,673 psi | 75% | 2861 fps | 99.1% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 53,069 psi | 86% | 2799 fps | 99.8% |
| Bofors RP3 | <<locked>> | 90% | 55,448 psi | 89% | 2828 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 55,100 psi | 89% | 2795 fps | 97.9% |
| Hodgdon Benchmark | <<locked>> | 82% | 54,201 psi | 87% | 2720 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 55,230 psi | 89% | 2815 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 52,547 psi | 85% | 2785 fps | 99.4% |
| Hodgdon H414 | <<locked>> | 96% | 55,811 psi | 90% | 2890 fps | 98.6% |
| Hodgdon H4350 | <<locked>> | 92% | 53,113 psi | 86% | 2802 fps | 96.9% |
| Hodgdon H4895 | <<locked>> | 84% | 54,215 psi | 87% | 2799 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 54,331 psi | 88% | 2825 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 53,635 psi | 87% | 2828 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 52,547 psi | 85% | 2871 fps | 97.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,810 psi | 58% | 1716 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 55,172 psi | 89% | 2799 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 54,027 psi | 87% | 2772 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 54,128 psi | 87% | 2772 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 86% | 53,780 psi | 87% | 2749 fps | 98.1% |
| IMR 4350 | <<locked>> | 98% | 55,622 psi | 90% | 2825 fps | 98% |
| IMR 4451 Enduron | <<locked>> | 92% | 53,911 psi | 87% | 2782 fps | 98.1% |
| IMR 4831 | <<locked>> | 98% | 53,621 psi | 86% | 2831 fps | 99.8% |
| IMR 4895 | <<locked>> | 86% | 53,040 psi | 86% | 2808 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 55,970 psi | 90% | 2785 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 53,461 psi | 86% | 2762 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 53,026 psi | 86% | 2713 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 54,128 psi | 87% | 2769 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 53,243 psi | 86% | 2772 fps | 99% |
| Lovex S070 | <<locked>> | 96% | 54,143 psi | 87% | 2808 fps | 98.4% |
| Norma 201 | <<locked>> | 86% | 55,550 psi | 90% | 2779 fps | 100% |
| Norma 202 | <<locked>> | 84% | 52,968 psi | 85% | 2733 fps | 100% |
| Norma 203B | <<locked>> | 88% | 54,476 psi | 88% | 2818 fps | 100% |
| Norma 204 | <<locked>> | 96% | 52,605 psi | 85% | 2818 fps | 96.2% |
| Norma MRPᴾ | <<locked>> | 100% | 46,673 psi | 75% | 2822 fps | 96.8% |
| Norma URP | <<locked>> | 98% | 55,970 psi | 90% | 2884 fps | 99.9% |
| Ramshot Big Game | <<locked>> | 88% | 55,071 psi | 89% | 2844 fps | 100% |
| Ramshot Hunter | <<locked>> | 98% | 54,491 psi | 88% | 2881 fps | 99% |
| Ramshot TAC | <<locked>> | 84% | 55,956 psi | 90% | 2805 fps | 99.4% |
| Ramshot Wild Boar | <<locked>> | 84% | 55,999 psi | 90% | 2825 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,390 psi | 59% | 1755 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 52,736 psi | 85% | 2766 fps | 98.5% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 55,637 psi | 90% | 2894 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 55,419 psi | 89% | 2930 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 52,721 psi | 85% | 2861 fps | 99.6% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 56,014 psi | 90% | 2949 fps | 99.8% |
| Rottweil R 901 | <<locked>> | 82% | 53,243 psi | 86% | 2710 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 56,057 psi | 90% | 2776 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 55,288 psi | 89% | 2818 fps | 100% |
| Rottweil R 905ᴾ | <<locked>> | 100% | 49,342 psi | 80% | 2792 fps | 96% |
| Rottweil R 907 | <<locked>> | 94% | 55,100 psi | 89% | 2795 fps | 97.9% |
| Shooters World Long Rifle | <<locked>> | 94% | 53,243 psi | 86% | 2772 fps | 99% |
| Shooters World Match Rifle | <<locked>> | 84% | 53,461 psi | 86% | 2762 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 54,128 psi | 87% | 2769 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 54,143 psi | 87% | 2808 fps | 98.4% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 53,243 psi | 86% | 2825 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 54,549 psi | 88% | 2785 fps | 99.5% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 55,158 psi | 89% | 2805 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 53,664 psi | 87% | 2671 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 53,809 psi | 87% | 2667 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 53,417 psi | 86% | 2726 fps | 98% |
| Somchem S335 | <<locked>> | 84% | 53,229 psi | 86% | 2671 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 54,099 psi | 87% | 2776 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 55,608 psi | 90% | 2815 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 54,157 psi | 87% | 2887 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 50,154 psi | 81% | 2772 fps | 97% |
| Vihtavuori N133 | <<locked>> | 84% | 54,012 psi | 87% | 2654 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 55,985 psi | 90% | 2740 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 53,243 psi | 86% | 2710 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 53,476 psi | 86% | 2746 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 54,882 psi | 89% | 2828 fps | 99.8% |
| Vihtavuori N530 | <<locked>> | 82% | 52,837 psi | 85% | 2733 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 54,839 psi | 88% | 2756 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 53,896 psi | 87% | 2835 fps | 99.6% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 45,905 psi | 74% | 2769 fps | 99.4% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 54,665 psi | 88% | 2802 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 53,026 psi | 86% | 2785 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 52,562 psi | 85% | 2841 fps | 98.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 37,289 psi | 60% | 2713 fps | 99.7% |
| Winchester StaBALL Match | <<locked>> | 86% | 55,492 psi | 90% | 2818 fps | 100% |
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% | 51,024 psi | 82% | 2635 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 44,048 psi | 71% | 2572 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 51,097 psi | 82% | 2720 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 45,585 psi | 74% | 2598 fps | 95.6% |
| Accurate 3100 | <<locked>> | 96% | 38,334 psi | 62% | 2562 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 41,640 psi | 67% | 2572 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 32,895 psi | 53% | 2454 fps | 95.7% |
| ADI AR 2206H | <<locked>> | 80% | 47,079 psi | 76% | 2680 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 80% | 40,059 psi | 65% | 2533 fps | 98.3% |
| ADI AR 2209 | <<locked>> | 98% | 48,298 psi | 78% | 2762 fps | 95.2% |
| ADI Benchmark 8208 | <<locked>> | 80% | 49,124 psi | 79% | 2684 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 50,038 psi | 81% | 2664 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 43,149 psi | 70% | 2723 fps | 98.9% |
| Alliant Power Pro Varmint | <<locked>> | 98% | 47,979 psi | 77% | 2759 fps | 95.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 40,074 psi | 65% | 2559 fps | 99.4% |
| Alliant Reloder-15 | <<locked>> | 80% | 42,714 psi | 69% | 2618 fps | 98.9% |
| Alliant Reloder-16 | <<locked>> | 82% | 33,112 psi | 53% | 2467 fps | 95.8% |
| Alliant Reloder-17 | 36.3 gr | 80% | 34,490 psi | 56% | 2533 fps | 98.1% |
| Alliant Reloder-19 | <<locked>> | 98% | 47,297 psi | 76% | 2749 fps | 95.2% |
| Alliant Reloder-23 | <<locked>> | 88% | 28,805 psi | 46% | 2379 fps | 95.5% |
| Alliant Reloder-26 | <<locked>> | 92% | 35,230 psi | 57% | 2608 fps | 95.9% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 46,630 psi | 75% | 2690 fps | 99.1% |
| Bofors RP3 | <<locked>> | 80% | 39,769 psi | 64% | 2566 fps | 99.4% |
| Bofors RP7 | <<locked>> | 86% | 42,975 psi | 69% | 2585 fps | 95.2% |
| Hodgdon Benchmark | <<locked>> | 80% | 50,807 psi | 82% | 2671 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 48,443 psi | 78% | 2710 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 40,524 psi | 65% | 2569 fps | 97.5% |
| Hodgdon H414 | <<locked>> | 86% | 40,205 psi | 65% | 2615 fps | 95.1% |
| Hodgdon H4350 | <<locked>> | 88% | 46,659 psi | 75% | 2690 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 47,529 psi | 77% | 2690 fps | 99.9% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 28,514 psi | 46% | 2316 fps | 95.7% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 43,859 psi | 71% | 2671 fps | 99.8% |
| Hodgdon Superformance | 42.2 gr | 88% | 42,395 psi | 68% | 2680 fps | 95.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,745 psi | 43% | 1532 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 45,585 psi | 74% | 2644 fps | 99.8% |
| IMR 3031 | <<locked>> | 80% | 47,732 psi | 77% | 2684 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 42,090 psi | 68% | 2566 fps | 98.9% |
| IMR 4166 Enduron | <<locked>> | 80% | 44,628 psi | 72% | 2592 fps | 96.3% |
| IMR 4350 | <<locked>> | 90% | 43,192 psi | 70% | 2615 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 84% | 41,959 psi | 68% | 2566 fps | 95.4% |
| IMR 4831 | <<locked>> | 82% | 32,010 psi | 52% | 2418 fps | 95.4% |
| IMR 4895 | <<locked>> | 80% | 43,787 psi | 71% | 2648 fps | 99.4% |
| IMR 8208 XBR | <<locked>> | 80% | 49,124 psi | 79% | 2684 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 46,702 psi | 75% | 2661 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 46,934 psi | 76% | 2615 fps | 99.7% |
| Lovex S062 | <<locked>> | 80% | 42,177 psi | 68% | 2572 fps | 99.8% |
| Lovex S065 | <<locked>> | 82% | 36,825 psi | 59% | 2464 fps | 95.4% |
| Lovex S070 | <<locked>> | 86% | 39,624 psi | 64% | 2546 fps | 95.1% |
| Norma 201 | <<locked>> | 80% | 46,282 psi | 75% | 2635 fps | 100% |
| Norma 202 | <<locked>> | 80% | 46,702 psi | 75% | 2638 fps | 100% |
| Norma 203B | <<locked>> | 80% | 42,119 psi | 68% | 2608 fps | 99.2% |
| Norma 204 | <<locked>> | 94% | 49,153 psi | 79% | 2759 fps | 95.4% |
| Norma MRP | <<locked>> | 98% | 43,642 psi | 70% | 2759 fps | 95.9% |
| Norma URP | <<locked>> | 82% | 33,127 psi | 53% | 2457 fps | 95.6% |
| Ramshot Big Game | <<locked>> | 80% | 41,930 psi | 68% | 2625 fps | 99% |
| Ramshot Hunter | <<locked>> | 88% | 39,204 psi | 63% | 2602 fps | 95.8% |
| Ramshot TAC | <<locked>> | 80% | 48,994 psi | 79% | 2697 fps | 98.6% |
| Ramshot Wild Boar | <<locked>> | 80% | 48,820 psi | 79% | 2717 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,064 psi | 44% | 1568 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 40,698 psi | 66% | 2549 fps | 95.9% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 45,585 psi | 74% | 2730 fps | 99.3% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 36,709 psi | 59% | 2595 fps | 99.9% |
| ReloadSwiss RS 62 | <<locked>> | 82% | 32,605 psi | 53% | 2467 fps | 95.1% |
| ReloadSwiss RS 70 | 38.7 gr | 84% | 34,722 psi | 56% | 2526 fps | 95% |
| Rottweil R 901 | <<locked>> | 80% | 50,270 psi | 81% | 2667 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 44,063 psi | 71% | 2585 fps | 99.9% |
| Rottweil R 903 | <<locked>> | 80% | 37,550 psi | 61% | 2513 fps | 98.9% |
| Rottweil R 905 | <<locked>> | 98% | 46,064 psi | 74% | 2733 fps | 95.1% |
| Rottweil R 907 | <<locked>> | 86% | 42,975 psi | 69% | 2585 fps | 95.2% |
| Shooters World Long Rifle | <<locked>> | 82% | 36,825 psi | 59% | 2464 fps | 95.4% |
| Shooters World Match Rifle | <<locked>> | 80% | 46,702 psi | 75% | 2661 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 42,177 psi | 68% | 2572 fps | 99.8% |
| Shooters World SW4350 | <<locked>> | 86% | 39,624 psi | 64% | 2546 fps | 95.1% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 38,450 psi | 62% | 2562 fps | 98.5% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 47,805 psi | 77% | 2677 fps | 98.8% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 45,774 psi | 74% | 2654 fps | 99.6% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 47,239 psi | 76% | 2575 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 39,465 psi | 64% | 2448 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 86% | 41,147 psi | 66% | 2516 fps | 95.3% |
| Somchem S335 | <<locked>> | 80% | 47,137 psi | 76% | 2582 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 47,442 psi | 77% | 2671 fps | 99.7% |
| Somchem S355 | <<locked>> | 80% | 38,218 psi | 62% | 2516 fps | 98.8% |
| Somchem S365 | <<locked>> | 80% | 27,760 psi | 45% | 2352 fps | 96.9% |
| Somchem S385 | <<locked>> | 96% | 43,830 psi | 71% | 2661 fps | 95.4% |
| Vihtavuori N133 | <<locked>> | 80% | 47,616 psi | 77% | 2566 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 43,526 psi | 70% | 2559 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 44,280 psi | 71% | 2575 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 36,419 psi | 59% | 2451 fps | 99.4% |
| Vihtavuori N160 | <<locked>> | 80% | 32,285 psi | 52% | 2402 fps | 95.1% |
| Vihtavuori N530 | <<locked>> | 80% | 49,400 psi | 80% | 2680 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 42,583 psi | 69% | 2566 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 34,127 psi | 55% | 2461 fps | 95.7% |
| Vihtavuori N555 | <<locked>> | 88% | 30,908 psi | 50% | 2451 fps | 95.6% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 32,140 psi | 52% | 2382 fps | 97.4% |
| Winchester 748 | <<locked>> | 80% | 49,574 psi | 80% | 2730 fps | 100% |
| Winchester 760 | <<locked>> | 86% | 40,205 psi | 65% | 2615 fps | 95.1% |
| Winchester StaBALL HD | <<locked>> | 92% | 28,761 psi | 46% | 2454 fps | 96.1% |
| Winchester StaBALL Match | <<locked>> | 80% | 45,237 psi | 73% | 2657 fps | 99.8% |
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 98 powders for .25 Creedmoor loaded with the .257 | 120gr | Speer Boat-Tail. ReloadSwiss RS 70 delivers the highest muzzle velocity at 2,949 fps; across all powders the maximum-charge window runs from 1,716 fps to 2,949 fps. Accurate 3100 gives the best case fill at 100 %, and 98 of the 98 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (427 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 120.0 gr projectile in 0.257" calls for a 1:10.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, ADI AR 2209, Alliant Power Pro Varmint 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. ReloadSwiss RS 70, Alliant Reloder-17, Hodgdon Superformance rank at the top here: for .25 Creedmoor with the .257 | 120gr | Speer Boat-Tail 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.