Load Specifications
Bullet Manufacturer:Sierra
Bullet Weight:117 gr
Bullet Diameter:0.257"
Bullet Length:<<locked>>
Caliber:.25 GT load data
Case Length (l3):1.725"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:43.5 Grains of Water
Primer Size:Small Rifle (SR)
Barrel Length:24"
Max. allowed Pressure:62,001 psi
Recommended Twist Rate:1:11.5
Load data in caliber .25 GT with .257 | 117gr | Sierra SPT Pro-Hunter bullet and 103 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 60, Alliant Power Pro 2000-MR and ReloadSwiss RS 52.
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% | 52,910 psi | 85% | 2608 fps | 100% |
| Accurate 2460 | <<locked>> | 84% | 54,882 psi | 89% | 2684 fps | 100% |
| Accurate 2495 | <<locked>> | 92% | 53,925 psi | 87% | 2671 fps | 100% |
| Accurate 2520 | <<locked>> | 86% | 52,953 psi | 85% | 2694 fps | 100% |
| Accurate 2700 | <<locked>> | 92% | 54,317 psi | 88% | 2664 fps | 96% |
| Accurate 4064 | <<locked>> | 94% | 54,157 psi | 87% | 2717 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 49,661 psi | 80% | 2730 fps | 98.6% |
| Accurate LT-30 | <<locked>> | 82% | 55,390 psi | 89% | 2595 fps | 100% |
| Accurate LT-32 | <<locked>> | 82% | 55,869 psi | 90% | 2621 fps | 100% |
| ADI AR 2206H | <<locked>> | 90% | 55,187 psi | 89% | 2746 fps | 99.8% |
| ADI AR 2208 | <<locked>> | 94% | 52,968 psi | 85% | 2697 fps | 99.3% |
| ADI Benchmark 8208 | <<locked>> | 88% | 54,505 psi | 88% | 2703 fps | 100% |
| Alliant AR-Comp | <<locked>> | 88% | 54,897 psi | 89% | 2684 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 82% | 52,591 psi | 85% | 2753 fps | 99.9% |
| Alliant Power Pro 2000-MR | <<locked>> | 92% | 54,549 psi | 88% | 2854 fps | 99.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 96% | 55,535 psi | 90% | 2762 fps | 100% |
| Alliant Reloder-10x | <<locked>> | 84% | 55,941 psi | 90% | 2654 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 92% | 53,330 psi | 86% | 2740 fps | 99.5% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 48,515 psi | 78% | 2730 fps | 98.7% |
| Alliant Reloder-17 | <<locked>> | 98% | 52,808 psi | 85% | 2828 fps | 99.9% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 34,519 psi | 56% | 2474 fps | 96.5% |
| Baschieri & Pellagri 106 | <<locked>> | 82% | 54,766 psi | 88% | 2598 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 90% | 54,940 psi | 89% | 2762 fps | 99.3% |
| Bofors RP3 | <<locked>> | 94% | 52,924 psi | 85% | 2733 fps | 100% |
| Bofors RP7 | <<locked>> | 98% | 53,505 psi | 86% | 2694 fps | 96.1% |
| Hodgdon Benchmark | <<locked>> | 86% | 53,243 psi | 86% | 2641 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 88% | 53,505 psi | 86% | 2733 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 86% | 55,376 psi | 89% | 2825 fps | 99.7% |
| Hodgdon H322 | <<locked>> | 84% | 55,114 psi | 89% | 2697 fps | 100% |
| Hodgdon H335 | <<locked>> | 82% | 52,837 psi | 85% | 2680 fps | 100% |
| Hodgdon H380 | <<locked>> | 94% | 53,940 psi | 87% | 2740 fps | 98.8% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 52,808 psi | 85% | 2776 fps | 96.8% |
| Hodgdon H4895 | <<locked>> | 90% | 55,666 psi | 90% | 2756 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 44,802 psi | 72% | 2621 fps | 99.1% |
| Hodgdon LEVERevolution | <<locked>> | 92% | 54,940 psi | 89% | 2792 fps | 100% |
| Hodgdon Superformanceᴾ | <<locked>> | 100% | 54,157 psi | 87% | 2812 fps | 96.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,925 psi | 56% | 1634 fps | 100% |
| Hodgdon VARGET | <<locked>> | 90% | 53,635 psi | 87% | 2710 fps | 99.9% |
| IMR 3031 | <<locked>> | 90% | 55,187 psi | 89% | 2740 fps | 100% |
| IMR 4064 | <<locked>> | 94% | 55,796 psi | 90% | 2730 fps | 99.7% |
| IMR 4166 Enduron | <<locked>> | 90% | 53,098 psi | 86% | 2661 fps | 96.6% |
| IMR 4198 | <<locked>> | 82% | 53,316 psi | 86% | 2579 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 98% | 55,361 psi | 89% | 2723 fps | 97% |
| IMR 4831ᴾ | <<locked>> | 100% | 46,978 psi | 76% | 2671 fps | 98.3% |
| IMR 4895 | <<locked>> | 92% | 54,650 psi | 88% | 2769 fps | 99.8% |
| IMR 8208 XBR | <<locked>> | 88% | 54,505 psi | 88% | 2703 fps | 100% |
| Lovex D073.5 | <<locked>> | 84% | 54,824 psi | 88% | 2694 fps | 100% |
| Lovex D073.6 | <<locked>> | 90% | 54,549 psi | 88% | 2726 fps | 100% |
| Lovex S060 | <<locked>> | 90% | 55,579 psi | 90% | 2684 fps | 99.8% |
| Lovex S062 | <<locked>> | 94% | 55,521 psi | 90% | 2726 fps | 100% |
| Lovex S065ᴾ | <<locked>> | 100% | 54,418 psi | 88% | 2720 fps | 98.2% |
| Lovex S070ᴾ | <<locked>> | 100% | 51,822 psi | 84% | 2700 fps | 96.7% |
| Norma 201 | <<locked>> | 90% | 53,969 psi | 87% | 2694 fps | 100% |
| Norma 202 | <<locked>> | 90% | 54,447 psi | 88% | 2700 fps | 100% |
| Norma 203B | <<locked>> | 94% | 55,782 psi | 90% | 2776 fps | 99.9% |
| Norma URPᴾ | <<locked>> | 100% | 49,182 psi | 79% | 2723 fps | 98.5% |
| Ramshot Big Game | <<locked>> | 92% | 52,359 psi | 84% | 2746 fps | 99.6% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 48,080 psi | 78% | 2707 fps | 96.6% |
| Ramshot TAC | <<locked>> | 88% | 54,940 psi | 89% | 2720 fps | 98.4% |
| Ramshot Wild Boar | <<locked>> | 88% | 54,230 psi | 87% | 2740 fps | 99.7% |
| Ramshot X-Terminator | <<locked>> | 86% | 55,796 psi | 90% | 2710 fps | 99.8% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,534 psi | 57% | 1677 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 84% | 54,375 psi | 88% | 2690 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 94% | 54,795 psi | 88% | 2723 fps | 97.6% |
| ReloadSwiss RS 52 | <<locked>> | 90% | 53,040 psi | 86% | 2799 fps | 99.5% |
| ReloadSwiss RS 60 | <<locked>> | 96% | 52,533 psi | 85% | 2831 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 49,052 psi | 79% | 2746 fps | 98.3% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 49,734 psi | 80% | 2766 fps | 97.9% |
| Rottweil R 901 | <<locked>> | 88% | 55,129 psi | 89% | 2680 fps | 100% |
| Rottweil R 902 | <<locked>> | 92% | 54,665 psi | 88% | 2697 fps | 100% |
| Rottweil R 903 | <<locked>> | 96% | 52,286 psi | 84% | 2717 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 98% | 53,505 psi | 86% | 2694 fps | 96.1% |
| Shooters World Long Rifleᴾ | <<locked>> | 100% | 54,418 psi | 88% | 2720 fps | 98.2% |
| Shooters World Match Rifle | <<locked>> | 90% | 54,549 psi | 88% | 2726 fps | 100% |
| Shooters World Precision | <<locked>> | 94% | 55,521 psi | 90% | 2726 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 51,822 psi | 84% | 2700 fps | 96.7% |
| Shooters World Tactical Rifle | <<locked>> | 82% | 54,012 psi | 87% | 2661 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 96% | 54,491 psi | 88% | 2782 fps | 99.8% |
| SNPE Vectan SP 3 | <<locked>> | 82% | 53,635 psi | 87% | 2635 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 88% | 52,953 psi | 85% | 2694 fps | 98.5% |
| SNPE Vectan SP 9 | <<locked>> | 90% | 53,722 psi | 87% | 2720 fps | 99.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 88% | 52,895 psi | 85% | 2598 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 96% | 55,724 psi | 90% | 2635 fps | 100% |
| SNPE Vectan Tubal 7000ᴾ | <<locked>> | 100% | 54,766 psi | 88% | 2671 fps | 96.9% |
| Somchem S321 | <<locked>> | 86% | 56,043 psi | 90% | 2743 fps | 100% |
| Somchem S335 | <<locked>> | 90% | 55,056 psi | 89% | 2638 fps | 100% |
| Somchem S341 | <<locked>> | 88% | 52,446 psi | 85% | 2687 fps | 99.6% |
| Somchem S355 | <<locked>> | 96% | 53,272 psi | 86% | 2723 fps | 99.9% |
| Somchem S365ᴾ | <<locked>> | 100% | 43,918 psi | 71% | 2674 fps | 99.8% |
| Vihtavuori N130 | <<locked>> | 86% | 55,927 psi | 90% | 2608 fps | 100% |
| Vihtavuori N133 | <<locked>> | 88% | 52,953 psi | 85% | 2585 fps | 100% |
| Vihtavuori N135 | <<locked>> | 92% | 54,056 psi | 87% | 2664 fps | 100% |
| Vihtavuori N140 | <<locked>> | 92% | 54,969 psi | 89% | 2680 fps | 100% |
| Vihtavuori N150 | <<locked>> | 98% | 54,752 psi | 88% | 2703 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 51,880 psi | 84% | 2723 fps | 98.8% |
| Vihtavuori N530 | <<locked>> | 88% | 55,347 psi | 89% | 2707 fps | 100% |
| Vihtavuori N540 | <<locked>> | 92% | 53,185 psi | 86% | 2677 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 50,937 psi | 82% | 2726 fps | 98.5% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 36,840 psi | 59% | 2546 fps | 96.5% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 52,518 psi | 85% | 2703 fps | 99.9% |
| Winchester 748 | <<locked>> | 88% | 54,520 psi | 88% | 2749 fps | 100% |
| Winchester 760ᴾ | <<locked>> | 100% | 53,287 psi | 86% | 2785 fps | 96.9% |
| Winchester StaBALL Match | <<locked>> | 90% | 53,330 psi | 86% | 2726 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% | 44,280 psi | 71% | 2487 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 48,167 psi | 78% | 2589 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 36,724 psi | 59% | 2405 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 43,163 psi | 70% | 2543 fps | 99.9% |
| Accurate 2700 | <<locked>> | 90% | 51,169 psi | 83% | 2615 fps | 95.3% |
| Accurate 4064 | <<locked>> | 80% | 34,708 psi | 56% | 2392 fps | 99.6% |
| Accurate 4350 | <<locked>> | 90% | 34,853 psi | 56% | 2454 fps | 95% |
| Accurate LT-30 | <<locked>> | 80% | 52,170 psi | 84% | 2552 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 52,576 psi | 85% | 2579 fps | 100% |
| ADI AR 2206H | <<locked>> | 80% | 40,437 psi | 65% | 2497 fps | 97.9% |
| ADI AR 2208 | <<locked>> | 80% | 34,621 psi | 56% | 2356 fps | 95.4% |
| ADI Benchmark 8208 | <<locked>> | 80% | 42,467 psi | 68% | 2510 fps | 99.2% |
| Alliant AR-Comp | <<locked>> | 80% | 42,163 psi | 68% | 2510 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 49,327 psi | 80% | 2700 fps | 99.7% |
| Alliant Power Pro 2000-MR | 30.9 gr | 80% | 36,492 psi | 59% | 2507 fps | 95.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 33,649 psi | 54% | 2372 fps | 97% |
| Alliant Reloder-10x | <<locked>> | 80% | 49,850 psi | 80% | 2575 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 36,303 psi | 59% | 2431 fps | 96.3% |
| Alliant Reloder-16 | <<locked>> | 90% | 35,940 psi | 58% | 2474 fps | 95.2% |
| Alliant Reloder-17 | <<locked>> | 82% | 31,125 psi | 50% | 2382 fps | 95.1% |
| Alliant Reloder-23 | <<locked>> | 98% | 32,503 psi | 52% | 2421 fps | 95.5% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 51,329 psi | 83% | 2552 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 39,334 psi | 63% | 2493 fps | 96.5% |
| Bofors RP3 | <<locked>> | 80% | 33,011 psi | 53% | 2369 fps | 96.9% |
| Bofors RP7 | <<locked>> | 96% | 50,343 psi | 81% | 2644 fps | 95.4% |
| Hodgdon Benchmark | <<locked>> | 80% | 44,570 psi | 72% | 2507 fps | 99.7% |
| Hodgdon BL-C2 | <<locked>> | 80% | 40,799 psi | 66% | 2526 fps | 99.3% |
| Hodgdon CFE223 | <<locked>> | 80% | 44,715 psi | 72% | 2654 fps | 98.4% |
| Hodgdon H322 | <<locked>> | 80% | 48,631 psi | 78% | 2608 fps | 100% |
| Hodgdon H335 | <<locked>> | 80% | 49,313 psi | 80% | 2628 fps | 100% |
| Hodgdon H380 | <<locked>> | 84% | 38,885 psi | 63% | 2477 fps | 95.6% |
| Hodgdon H414 | <<locked>> | 96% | 46,267 psi | 75% | 2667 fps | 95.3% |
| Hodgdon H4895 | <<locked>> | 80% | 40,785 psi | 66% | 2510 fps | 98.5% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 30,850 psi | 50% | 2323 fps | 95.2% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 36,608 psi | 59% | 2474 fps | 98% |
| Hodgdon Superformance | <<locked>> | 98% | 50,459 psi | 81% | 2753 fps | 95.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,107 psi | 42% | 1463 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 39,189 psi | 63% | 2461 fps | 98.1% |
| IMR 3031 | <<locked>> | 80% | 39,871 psi | 64% | 2510 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 36,303 psi | 59% | 2388 fps | 96.3% |
| IMR 4166 Enduron | <<locked>> | 86% | 46,746 psi | 75% | 2556 fps | 95.2% |
| IMR 4198 | <<locked>> | 80% | 50,067 psi | 81% | 2536 fps | 100% |
| IMR 4451 Enduron | <<locked>> | 92% | 46,354 psi | 75% | 2579 fps | 95% |
| IMR 4831 | <<locked>> | 92% | 36,158 psi | 58% | 2467 fps | 95.5% |
| IMR 4895 | <<locked>> | 80% | 37,159 psi | 60% | 2461 fps | 97.2% |
| IMR 8208 XBR | <<locked>> | 80% | 42,467 psi | 68% | 2510 fps | 99.2% |
| Lovex D073.5 | <<locked>> | 80% | 47,674 psi | 77% | 2589 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 39,088 psi | 63% | 2480 fps | 99.7% |
| Lovex S060 | <<locked>> | 80% | 40,944 psi | 66% | 2441 fps | 98% |
| Lovex S062 | <<locked>> | 80% | 35,853 psi | 58% | 2392 fps | 98% |
| Lovex S065 | <<locked>> | 92% | 42,453 psi | 68% | 2520 fps | 95.7% |
| Lovex S070 | <<locked>> | 96% | 45,498 psi | 73% | 2595 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 39,784 psi | 64% | 2457 fps | 98.8% |
| Norma 202 | <<locked>> | 80% | 39,697 psi | 64% | 2467 fps | 99.9% |
| Norma 203B | <<locked>> | 80% | 35,708 psi | 58% | 2421 fps | 96.7% |
| Norma URP | <<locked>> | 90% | 35,708 psi | 58% | 2464 fps | 95% |
| Ramshot Big Game | <<locked>> | 80% | 35,099 psi | 57% | 2428 fps | 96.2% |
| Ramshot Hunter | <<locked>> | 96% | 42,656 psi | 69% | 2608 fps | 95.2% |
| Ramshot TAC | <<locked>> | 80% | 42,438 psi | 68% | 2510 fps | 95.9% |
| Ramshot Wild Boar | <<locked>> | 80% | 41,582 psi | 67% | 2530 fps | 98.1% |
| Ramshot X-Terminator | <<locked>> | 80% | 46,108 psi | 74% | 2559 fps | 98.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,397 psi | 43% | 1499 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 47,761 psi | 77% | 2592 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 45,020 psi | 73% | 2566 fps | 95.5% |
| ReloadSwiss RS 52 | 30 gr | 80% | 37,724 psi | 61% | 2523 fps | 96.7% |
| ReloadSwiss RS 60 | 30.4 gr | 80% | 30,937 psi | 50% | 2388 fps | 97.7% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 37,565 psi | 61% | 2533 fps | 95.5% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 40,756 psi | 66% | 2595 fps | 95.4% |
| Rottweil R 901 | <<locked>> | 80% | 43,729 psi | 71% | 2507 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 37,898 psi | 61% | 2411 fps | 98.4% |
| Rottweil R 903 | <<locked>> | 80% | 31,169 psi | 50% | 2320 fps | 95.9% |
| Rottweil R 907 | <<locked>> | 96% | 50,343 psi | 81% | 2644 fps | 95.4% |
| Shooters World Long Rifle | <<locked>> | 92% | 42,453 psi | 68% | 2520 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 39,088 psi | 63% | 2480 fps | 99.7% |
| Shooters World Precision | <<locked>> | 80% | 35,853 psi | 58% | 2392 fps | 98% |
| Shooters World SW4350 | <<locked>> | 96% | 45,498 psi | 73% | 2595 fps | 95.2% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 50,357 psi | 81% | 2608 fps | 99.8% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 32,343 psi | 52% | 2369 fps | 95.2% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 50,357 psi | 81% | 2589 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 40,364 psi | 65% | 2477 fps | 95.9% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 39,160 psi | 63% | 2470 fps | 97.6% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 41,147 psi | 66% | 2418 fps | 99.9% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 33,924 psi | 55% | 2290 fps | 99.8% |
| SNPE Vectan Tubal 7000 | <<locked>> | 96% | 48,153 psi | 78% | 2572 fps | 95.6% |
| Somchem S321 | <<locked>> | 80% | 45,629 psi | 74% | 2582 fps | 99.7% |
| Somchem S335 | <<locked>> | 80% | 40,857 psi | 66% | 2425 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 40,059 psi | 65% | 2477 fps | 97.7% |
| Somchem S355 | <<locked>> | 80% | 32,271 psi | 52% | 2329 fps | 96.1% |
| Somchem S365 | <<locked>> | 86% | 28,036 psi | 45% | 2306 fps | 95.5% |
| Vihtavuori N130 | <<locked>> | 80% | 46,572 psi | 75% | 2480 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 41,336 psi | 67% | 2415 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 36,782 psi | 59% | 2398 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 37,666 psi | 61% | 2408 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 80% | 30,530 psi | 49% | 2270 fps | 96.9% |
| Vihtavuori N160 | <<locked>> | 90% | 37,304 psi | 60% | 2464 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 42,351 psi | 68% | 2503 fps | 99.2% |
| Vihtavuori N540 | <<locked>> | 80% | 36,085 psi | 58% | 2392 fps | 99.5% |
| Vihtavuori N550 | <<locked>> | 90% | 36,811 psi | 59% | 2470 fps | 95.2% |
| Vihtavuori N555 | <<locked>> | 98% | 34,272 psi | 55% | 2487 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 31,183 psi | 50% | 2293 fps | 95.3% |
| Winchester 748 | <<locked>> | 80% | 41,756 psi | 67% | 2549 fps | 99.6% |
| Winchester 760 | <<locked>> | 96% | 46,673 psi | 75% | 2674 fps | 95.4% |
| Winchester StaBALL Match | <<locked>> | 80% | 38,261 psi | 62% | 2470 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 103 powders for .25 GT loaded with the .257 | 117gr | Sierra SPT Pro-Hunter. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 2,854 fps; across all powders the maximum-charge window runs from 1,634 fps to 2,854 fps. Accurate 4350 gives the best case fill at 100 %, and 103 of the 103 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (427 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 117.0 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. ReloadSwiss RS 60, Alliant Power Pro 2000-MR, ReloadSwiss RS 52 rank at the top here: for .25 GT with the .257 | 117gr | Sierra SPT Pro-Hunter 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.