Load Specifications
Bullet Manufacturer:Nosler
Bullet Weight:120 gr
Bullet Diameter:0.257"
Bullet Length:<<locked>>
Caliber:.25 Creedmoor load data
Case Length (l3):1.92"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:51.5 Grains of Water
Primer Size:Large Rifle (LR)
Barrel Length:24"
Max. allowed Pressure:62,001 psi
Recommended Twist Rate:1:10.0
Load data in caliber .25 Creedmoor with .257 | 120gr | Nosler Partition bullet and 98 powders. The key underlying parameters are shown in the table above.
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>> | 82% | 52,968 psi | 85% | 2654 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 55,085 psi | 89% | 2723 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 53,243 psi | 86% | 2740 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 54,360 psi | 88% | 2730 fps | 97.3% |
| Accurate 3100ᴾ | <<locked>> | 100% | 42,221 psi | 68% | 2628 fps | 96.6% |
| Accurate 4064 | <<locked>> | 90% | 55,434 psi | 89% | 2776 fps | 100% |
| Accurate 4350 | <<locked>> | 98% | 55,245 psi | 89% | 2861 fps | 99.8% |
| ADI AR 2206H | <<locked>> | 86% | 55,463 psi | 89% | 2802 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 53,243 psi | 86% | 2756 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 84% | 54,607 psi | 88% | 2756 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 55,434 psi | 89% | 2726 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 55,317 psi | 89% | 2923 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 53,272 psi | 86% | 2779 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 53,896 psi | 87% | 2799 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 98% | 52,779 psi | 85% | 2861 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 94% | 53,766 psi | 87% | 2897 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 40,292 psi | 65% | 2661 fps | 99.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 45,223 psi | 73% | 2822 fps | 98.7% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 55,434 psi | 89% | 2822 fps | 99.8% |
| Bofors RP3 | <<locked>> | 90% | 53,737 psi | 87% | 2792 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 53,650 psi | 87% | 2759 fps | 97.4% |
| Hodgdon Benchmark | <<locked>> | 84% | 55,999 psi | 90% | 2736 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 53,954 psi | 87% | 2785 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 82% | 55,651 psi | 90% | 2881 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 54,592 psi | 88% | 2805 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 96% | 54,331 psi | 88% | 2858 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 94% | 54,897 psi | 89% | 2818 fps | 97% |
| Hodgdon H4895 | <<locked>> | 86% | 56,043 psi | 90% | 2815 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 52,330 psi | 84% | 2789 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 55,564 psi | 90% | 2848 fps | 100% |
| Hodgdon Superformance | <<locked>> | 96% | 54,708 psi | 88% | 2890 fps | 97.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,679 psi | 58% | 1699 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 53,824 psi | 87% | 2766 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 52,779 psi | 85% | 2749 fps | 100% |
| IMR 4064 | <<locked>> | 90% | 56,101 psi | 90% | 2789 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 88% | 55,854 psi | 90% | 2766 fps | 98.2% |
| IMR 4350 | <<locked>> | 98% | 53,911 psi | 87% | 2785 fps | 97.5% |
| IMR 4451 Enduron | <<locked>> | 94% | 55,637 psi | 90% | 2792 fps | 98.2% |
| IMR 4831ᴾ | <<locked>> | 100% | 55,390 psi | 89% | 2848 fps | 99.8% |
| IMR 4895 | <<locked>> | 88% | 55,288 psi | 89% | 2831 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 54,607 psi | 88% | 2756 fps | 100% |
| Lovex D073.6 | <<locked>> | 86% | 55,317 psi | 89% | 2779 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 54,839 psi | 88% | 2730 fps | 100% |
| Lovex S062 | <<locked>> | 90% | 55,999 psi | 90% | 2782 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 54,897 psi | 89% | 2785 fps | 99.1% |
| Lovex S070 | <<locked>> | 98% | 55,970 psi | 90% | 2822 fps | 98.5% |
| Norma 201 | <<locked>> | 86% | 54,186 psi | 87% | 2749 fps | 100% |
| Norma 202 | <<locked>> | 86% | 54,723 psi | 88% | 2749 fps | 100% |
| Norma 203B | <<locked>> | 88% | 53,142 psi | 86% | 2789 fps | 100% |
| Norma 204 | <<locked>> | 98% | 54,621 psi | 88% | 2835 fps | 96.4% |
| Norma MRPᴾ | <<locked>> | 100% | 44,889 psi | 72% | 2776 fps | 96% |
| Norma URP | <<locked>> | 98% | 54,012 psi | 87% | 2844 fps | 99.7% |
| Ramshot Big Game | <<locked>> | 88% | 53,476 psi | 86% | 2808 fps | 100% |
| Ramshot Hunter | <<locked>> | 98% | 52,750 psi | 85% | 2841 fps | 98.6% |
| Ramshot TAC | <<locked>> | 84% | 54,505 psi | 88% | 2772 fps | 99.1% |
| Ramshot Wild Boar | <<locked>> | 84% | 54,360 psi | 88% | 2792 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 55,434 psi | 89% | 2759 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,274 psi | 59% | 1742 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 54,810 psi | 88% | 2785 fps | 98.6% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 54,172 psi | 87% | 2864 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 53,461 psi | 86% | 2894 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 98% | 54,549 psi | 88% | 2877 fps | 99.7% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 54,418 psi | 88% | 2913 fps | 99.6% |
| Rottweil R 901 | <<locked>> | 84% | 55,288 psi | 89% | 2730 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 54,694 psi | 88% | 2746 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 53,548 psi | 86% | 2782 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 53,650 psi | 87% | 2759 fps | 97.4% |
| Shooters World Long Rifle | <<locked>> | 96% | 54,897 psi | 89% | 2785 fps | 99.1% |
| Shooters World Match Rifle | <<locked>> | 86% | 55,317 psi | 89% | 2779 fps | 100% |
| Shooters World Precision | <<locked>> | 90% | 55,999 psi | 90% | 2782 fps | 100% |
| Shooters World SW4350 | <<locked>> | 98% | 55,970 psi | 90% | 2822 fps | 98.5% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 55,303 psi | 89% | 2844 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 52,924 psi | 85% | 2749 fps | 99.3% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 53,925 psi | 87% | 2776 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 55,521 psi | 90% | 2684 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 92% | 55,840 psi | 90% | 2684 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 55,347 psi | 89% | 2743 fps | 98.1% |
| Somchem S321 | <<locked>> | 82% | 55,869 psi | 90% | 2789 fps | 100% |
| Somchem S335 | <<locked>> | 86% | 55,013 psi | 89% | 2684 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 52,866 psi | 85% | 2746 fps | 99.9% |
| Somchem S355 | <<locked>> | 92% | 53,983 psi | 87% | 2782 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 52,112 psi | 84% | 2848 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 48,486 psi | 78% | 2733 fps | 96.4% |
| Vihtavuori N130 | <<locked>> | 82% | 55,593 psi | 90% | 2651 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 55,796 psi | 90% | 2667 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 54,462 psi | 88% | 2710 fps | 100% |
| Vihtavuori N140 | <<locked>> | 88% | 55,550 psi | 90% | 2730 fps | 100% |
| Vihtavuori N150 | <<locked>> | 94% | 55,143 psi | 89% | 2756 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 52,939 psi | 85% | 2792 fps | 99.6% |
| Vihtavuori N530 | <<locked>> | 84% | 55,129 psi | 89% | 2756 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 53,650 psi | 87% | 2730 fps | 100% |
| Vihtavuori N550 | <<locked>> | 98% | 55,753 psi | 90% | 2851 fps | 99.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 44,382 psi | 72% | 2736 fps | 99.1% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 53,127 psi | 86% | 2769 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 54,853 psi | 88% | 2799 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 54,331 psi | 88% | 2858 fps | 98.2% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 36,114 psi | 58% | 2667 fps | 99.3% |
| Winchester StaBALL Match | <<locked>> | 86% | 53,853 psi | 87% | 2785 fps | 100% |
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 49,821 psi | 80% | 2608 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 42,830 psi | 69% | 2546 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 49,705 psi | 80% | 2690 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 44,498 psi | 72% | 2566 fps | 95% |
| Accurate 3100 | <<locked>> | 98% | 39,523 psi | 64% | 2579 fps | 95.8% |
| Accurate 4064 | <<locked>> | 80% | 40,480 psi | 65% | 2543 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 34,113 psi | 55% | 2477 fps | 95.9% |
| ADI AR 2206H | <<locked>> | 80% | 46,064 psi | 74% | 2651 fps | 99.5% |
| ADI AR 2208 | <<locked>> | 80% | 39,146 psi | 63% | 2503 fps | 97.9% |
| ADI Benchmark 8208 | <<locked>> | 80% | 48,095 psi | 78% | 2654 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 48,718 psi | 79% | 2638 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 41,974 psi | 68% | 2687 fps | 98.5% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 38,754 psi | 63% | 2523 fps | 99.1% |
| Alliant Reloder-15 | <<locked>> | 80% | 41,713 psi | 67% | 2589 fps | 98.6% |
| Alliant Reloder-16 | <<locked>> | 82% | 32,068 psi | 52% | 2431 fps | 95% |
| Alliant Reloder-17 | <<locked>> | 80% | 33,446 psi | 54% | 2497 fps | 97.5% |
| Alliant Reloder-23 | <<locked>> | 90% | 29,675 psi | 48% | 2395 fps | 95.7% |
| Alliant Reloder-26 | <<locked>> | 92% | 33,968 psi | 55% | 2566 fps | 95% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 45,078 psi | 73% | 2651 fps | 98.8% |
| Bofors RP3 | <<locked>> | 80% | 38,740 psi | 62% | 2536 fps | 99.2% |
| Bofors RP7 | <<locked>> | 88% | 44,802 psi | 72% | 2608 fps | 95.4% |
| Hodgdon Benchmark | <<locked>> | 80% | 49,835 psi | 80% | 2644 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 47,123 psi | 76% | 2680 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 80% | 51,982 psi | 84% | 2825 fps | 99.8% |
| Hodgdon H380 | <<locked>> | 80% | 39,291 psi | 63% | 2533 fps | 96.9% |
| Hodgdon H414 | <<locked>> | 88% | 41,553 psi | 67% | 2631 fps | 95.3% |
| Hodgdon H4350 | <<locked>> | 90% | 48,356 psi | 78% | 2710 fps | 95.6% |
| Hodgdon H4895 | <<locked>> | 80% | 46,485 psi | 75% | 2661 fps | 99.8% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 27,717 psi | 45% | 2283 fps | 95% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 42,554 psi | 69% | 2638 fps | 99.7% |
| Hodgdon Superformance | <<locked>> | 90% | 44,179 psi | 71% | 2707 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,701 psi | 43% | 1522 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 44,585 psi | 72% | 2615 fps | 99.6% |
| IMR 3031 | <<locked>> | 80% | 46,093 psi | 74% | 2648 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 41,075 psi | 66% | 2536 fps | 98.5% |
| IMR 4166 Enduron | <<locked>> | 80% | 43,468 psi | 70% | 2556 fps | 95.7% |
| IMR 4350 | <<locked>> | 92% | 44,759 psi | 72% | 2631 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 86% | 43,714 psi | 71% | 2589 fps | 95.6% |
| IMR 4831 | <<locked>> | 84% | 32,895 psi | 53% | 2431 fps | 95.5% |
| IMR 4895 | <<locked>> | 80% | 42,743 psi | 69% | 2618 fps | 99.2% |
| IMR 8208 XBR | <<locked>> | 80% | 48,095 psi | 78% | 2654 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 45,295 psi | 73% | 2628 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 45,948 psi | 74% | 2589 fps | 99.5% |
| Lovex S062 | <<locked>> | 80% | 41,162 psi | 66% | 2543 fps | 99.6% |
| Lovex S065 | <<locked>> | 84% | 38,174 psi | 62% | 2487 fps | 95.7% |
| Lovex S070 | <<locked>> | 88% | 41,249 psi | 67% | 2569 fps | 95.4% |
| Norma 201 | <<locked>> | 80% | 45,223 psi | 73% | 2605 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 45,266 psi | 73% | 2605 fps | 100% |
| Norma 203B | <<locked>> | 80% | 41,089 psi | 66% | 2579 fps | 98.9% |
| Norma 204 | <<locked>> | 96% | 50,952 psi | 82% | 2776 fps | 95.6% |
| Norma MRP | <<locked>> | 98% | 42,250 psi | 68% | 2720 fps | 95.2% |
| Norma URP | <<locked>> | 82% | 32,256 psi | 52% | 2425 fps | 95% |
| Ramshot Big Game | <<locked>> | 80% | 40,727 psi | 66% | 2592 fps | 98.7% |
| Ramshot Hunter | <<locked>> | 88% | 38,261 psi | 62% | 2569 fps | 95.2% |
| Ramshot TAC | <<locked>> | 80% | 47,892 psi | 77% | 2664 fps | 98.2% |
| Ramshot Wild Boar | <<locked>> | 80% | 47,601 psi | 77% | 2684 fps | 99.7% |
| Ramshot X-Terminator | <<locked>> | 80% | 51,924 psi | 84% | 2707 fps | 99.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,021 psi | 44% | 1555 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 39,610 psi | 64% | 2516 fps | 95.3% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 44,135 psi | 71% | 2694 fps | 99% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 35,607 psi | 57% | 2562 fps | 99.8% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 33,823 psi | 55% | 2493 fps | 95.4% |
| ReloadSwiss RS 70 | <<locked>> | 86% | 36,216 psi | 58% | 2552 fps | 95.4% |
| Rottweil R 901 | <<locked>> | 80% | 49,095 psi | 79% | 2638 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 42,975 psi | 69% | 2556 fps | 99.8% |
| Rottweil R 903 | <<locked>> | 80% | 36,274 psi | 59% | 2477 fps | 98.5% |
| Rottweil R 907 | <<locked>> | 88% | 44,802 psi | 72% | 2608 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 84% | 38,174 psi | 62% | 2487 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 45,295 psi | 73% | 2628 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 41,162 psi | 66% | 2543 fps | 99.6% |
| Shooters World SW4350 | <<locked>> | 88% | 41,249 psi | 67% | 2569 fps | 95.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 37,275 psi | 60% | 2526 fps | 98% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 46,224 psi | 75% | 2638 fps | 98.4% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 44,512 psi | 72% | 2621 fps | 99.4% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 46,514 psi | 75% | 2556 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 38,783 psi | 63% | 2425 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 42,627 psi | 69% | 2533 fps | 95.5% |
| Somchem S321 | <<locked>> | 80% | 51,880 psi | 84% | 2733 fps | 100% |
| Somchem S335 | <<locked>> | 80% | 46,151 psi | 74% | 2556 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 45,905 psi | 74% | 2635 fps | 99.5% |
| Somchem S355 | <<locked>> | 80% | 37,231 psi | 60% | 2487 fps | 98.5% |
| Somchem S365 | <<locked>> | 80% | 26,992 psi | 44% | 2320 fps | 96.3% |
| Somchem S385 | <<locked>> | 98% | 45,208 psi | 73% | 2677 fps | 95.6% |
| Vihtavuori N130 | <<locked>> | 80% | 52,402 psi | 85% | 2608 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 46,833 psi | 76% | 2546 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 42,641 psi | 69% | 2536 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 42,960 psi | 69% | 2543 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 35,215 psi | 57% | 2418 fps | 99.1% |
| Vihtavuori N160 | <<locked>> | 82% | 33,489 psi | 54% | 2425 fps | 95.4% |
| Vihtavuori N530 | <<locked>> | 80% | 48,399 psi | 78% | 2654 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 41,394 psi | 67% | 2536 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 33,098 psi | 53% | 2428 fps | 95% |
| Vihtavuori N555 | <<locked>> | 90% | 32,010 psi | 52% | 2470 fps | 95.9% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 31,096 psi | 50% | 2346 fps | 96.8% |
| Winchester 748 | <<locked>> | 80% | 48,196 psi | 78% | 2700 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 41,872 psi | 68% | 2638 fps | 95.4% |
| Winchester StaBALL HD | <<locked>> | 92% | 27,920 psi | 45% | 2411 fps | 95% |
| Winchester StaBALL Match | <<locked>> | 80% | 43,976 psi | 71% | 2625 fps | 99.6% |
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 | Nosler Partition. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,923 fps; across all powders the maximum-charge window runs from 1,699 fps to 2,923 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 1:10.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Reloder-23, Alliant Reloder-26 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. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.