Load Specifications
Bullet Manufacturer:Sierra
Bullet Weight:100 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:1:10.5
Load data in caliber .25 GT with .257 | 100gr | Sierra MatchKing bullet and 90 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>> | 90% | 53,592 psi | 86% | 2838 fps | 100% |
| Accurate 2200 | <<locked>> | 82% | 53,577 psi | 86% | 2917 fps | 98.1% |
| Accurate 2230 | <<locked>> | 82% | 54,346 psi | 88% | 2927 fps | 98.5% |
| Accurate 2460 | <<locked>> | 88% | 55,637 psi | 90% | 2907 fps | 100% |
| Accurate 2495 | <<locked>> | 96% | 53,519 psi | 86% | 2890 fps | 100% |
| Accurate 2520 | <<locked>> | 90% | 53,258 psi | 86% | 2910 fps | 100% |
| Accurate 4064 | <<locked>> | 98% | 53,098 psi | 86% | 2923 fps | 100% |
| Accurate LT-30 | <<locked>> | 84% | 53,911 psi | 87% | 2785 fps | 100% |
| Accurate LT-32 | <<locked>> | 84% | 54,331 psi | 88% | 2808 fps | 100% |
| ADI AR 2206H | <<locked>> | 94% | 55,521 psi | 90% | 2959 fps | 99% |
| ADI AR 2207 | <<locked>> | 82% | 54,984 psi | 89% | 2805 fps | 100% |
| ADI AR 2208 | <<locked>> | 98% | 53,505 psi | 86% | 2904 fps | 98.2% |
| ADI AR 2219 | <<locked>> | 84% | 53,896 psi | 87% | 2904 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 92% | 55,129 psi | 89% | 2920 fps | 99.6% |
| Alliant AR-Comp | <<locked>> | 92% | 54,273 psi | 88% | 2910 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 86% | 52,895 psi | 85% | 2972 fps | 99.2% |
| Alliant Power Pro 2000-MR | <<locked>> | 96% | 55,550 psi | 90% | 3071 fps | 98.5% |
| Alliant Reloder- TS 15.5ᴾ | <<locked>> | 100% | 55,405 psi | 89% | 2969 fps | 99.5% |
| Alliant Reloder-10x | <<locked>> | 86% | 53,592 psi | 86% | 2848 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 96% | 53,301 psi | 86% | 2943 fps | 98.4% |
| Alliant Reloder-17ᴾ | <<locked>> | 100% | 49,313 psi | 80% | 2966 fps | 98.6% |
| Baschieri & Pellagri 106 | <<locked>> | 84% | 52,649 psi | 85% | 2776 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 94% | 55,796 psi | 90% | 2976 fps | 98.2% |
| Bofors RP3ᴾ | <<locked>> | 100% | 55,912 psi | 90% | 2989 fps | 99.6% |
| Hodgdon Benchmark | <<locked>> | 90% | 54,259 psi | 88% | 2861 fps | 99.8% |
| Hodgdon BL-C2 | <<locked>> | 92% | 53,795 psi | 87% | 2949 fps | 99.8% |
| Hodgdon CFE223 | <<locked>> | 90% | 55,390 psi | 89% | 3038 fps | 98.7% |
| Hodgdon H322 | <<locked>> | 88% | 55,854 psi | 90% | 2930 fps | 100% |
| Hodgdon H335 | <<locked>> | 86% | 53,664 psi | 87% | 2907 fps | 100% |
| Hodgdon H380 | <<locked>> | 98% | 54,375 psi | 88% | 2943 fps | 97.4% |
| Hodgdon H4198 | <<locked>> | 82% | 55,840 psi | 90% | 2835 fps | 100% |
| Hodgdon H4895 | <<locked>> | 94% | 56,028 psi | 90% | 2972 fps | 99.4% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 39,001 psi | 63% | 2687 fps | 96% |
| Hodgdon LEVERevolution | <<locked>> | 96% | 54,520 psi | 88% | 2999 fps | 99.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,345 psi | 55% | 1762 fps | 100% |
| Hodgdon VARGET | <<locked>> | 94% | 54,186 psi | 87% | 2923 fps | 99.2% |
| IMR 3031 | <<locked>> | 94% | 55,129 psi | 89% | 2969 fps | 100% |
| IMR 4064 | <<locked>> | 96% | 52,591 psi | 85% | 2881 fps | 98.3% |
| IMR 4198 | <<locked>> | 86% | 53,998 psi | 87% | 2808 fps | 100% |
| IMR 4895 | <<locked>> | 96% | 54,650 psi | 88% | 2979 fps | 99% |
| IMR 8208 XBR | <<locked>> | 92% | 55,129 psi | 89% | 2920 fps | 99.6% |
| Lovex D073.4 | <<locked>> | 82% | 55,216 psi | 89% | 2913 fps | 100% |
| Lovex D073.5 | <<locked>> | 88% | 55,506 psi | 90% | 2913 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 94% | 54,708 psi | 88% | 2943 fps | 100% |
| Lovex S060 | <<locked>> | 92% | 52,982 psi | 85% | 2844 fps | 98.7% |
| Lovex S062 | <<locked>> | 98% | 55,172 psi | 89% | 2933 fps | 99.7% |
| Norma 200 | <<locked>> | 82% | 53,272 psi | 86% | 2818 fps | 100% |
| Norma 201 | <<locked>> | 94% | 54,447 psi | 88% | 2910 fps | 99.6% |
| Norma 202 | <<locked>> | 94% | 54,810 psi | 88% | 2920 fps | 100% |
| Norma 203B | <<locked>> | 98% | 55,651 psi | 90% | 2982 fps | 99.1% |
| Ramshot Big Game | <<locked>> | 96% | 52,823 psi | 85% | 2956 fps | 98.6% |
| Ramshot TAC | <<locked>> | 92% | 55,854 psi | 90% | 2927 fps | 96.9% |
| Ramshot Wild Boar | <<locked>> | 92% | 54,795 psi | 88% | 2953 fps | 98.9% |
| Ramshot X-Terminator | <<locked>> | 88% | 53,258 psi | 86% | 2871 fps | 98.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,447 psi | 56% | 1801 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 88% | 55,114 psi | 89% | 2913 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 98% | 54,940 psi | 89% | 2917 fps | 95.7% |
| ReloadSwiss RS 52 | <<locked>> | 94% | 52,837 psi | 85% | 3009 fps | 98.3% |
| ReloadSwiss RS 60ᴾ | <<locked>> | 100% | 52,765 psi | 85% | 3038 fps | 100% |
| Rottweil R 901 | <<locked>> | 92% | 55,347 psi | 89% | 2900 fps | 100% |
| Rottweil R 902 | <<locked>> | 96% | 54,650 psi | 88% | 2904 fps | 99.6% |
| Rottweil R 903ᴾ | <<locked>> | 100% | 51,837 psi | 84% | 2917 fps | 99.1% |
| Shooters World AR Plus | <<locked>> | 82% | 55,216 psi | 89% | 2913 fps | 100% |
| Shooters World Match Rifle | <<locked>> | 94% | 54,708 psi | 88% | 2943 fps | 100% |
| Shooters World Precision | <<locked>> | 98% | 55,172 psi | 89% | 2933 fps | 99.7% |
| Shooters World Tactical Rifle | <<locked>> | 86% | 55,376 psi | 89% | 2884 fps | 99.4% |
| SNPE Vectan BA6 1/2 | <<locked>> | 82% | 54,462 psi | 88% | 2546 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 84% | 54,317 psi | 88% | 2910 fps | 100% |
| SNPE Vectan SP 11ᴾ | <<locked>> | 100% | 54,041 psi | 87% | 2982 fps | 98.8% |
| SNPE Vectan SP 3 | <<locked>> | 86% | 54,230 psi | 87% | 2864 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 92% | 54,027 psi | 87% | 2904 fps | 97.1% |
| SNPE Vectan SP 9 | <<locked>> | 94% | 54,375 psi | 88% | 2933 fps | 98.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 92% | 53,606 psi | 86% | 2815 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 98% | 53,055 psi | 86% | 2812 fps | 100% |
| Somchem S321 | <<locked>> | 88% | 52,997 psi | 85% | 2907 fps | 99.6% |
| Somchem S335 | <<locked>> | 94% | 55,753 psi | 90% | 2861 fps | 100% |
| Somchem S341 | <<locked>> | 92% | 53,301 psi | 86% | 2900 fps | 98.6% |
| Somchem S355ᴾ | <<locked>> | 100% | 52,692 psi | 85% | 2920 fps | 99% |
| Somchem S365ᴾ | <<locked>> | 100% | 37,884 psi | 61% | 2733 fps | 97.3% |
| Vihtavuori N120 | <<locked>> | 82% | 54,882 psi | 89% | 2753 fps | 100% |
| Vihtavuori N130 | <<locked>> | 88% | 53,403 psi | 86% | 2792 fps | 100% |
| Vihtavuori N133 | <<locked>> | 92% | 53,388 psi | 86% | 2805 fps | 100% |
| Vihtavuori N135 | <<locked>> | 96% | 53,650 psi | 87% | 2881 fps | 100% |
| Vihtavuori N140 | <<locked>> | 96% | 55,274 psi | 89% | 2897 fps | 100% |
| Vihtavuori N150ᴾ | <<locked>> | 100% | 50,908 psi | 82% | 2854 fps | 99.5% |
| Vihtavuori N530 | <<locked>> | 92% | 55,970 psi | 90% | 2927 fps | 99.7% |
| Vihtavuori N540 | <<locked>> | 96% | 53,330 psi | 86% | 2890 fps | 100% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 46,615 psi | 75% | 2789 fps | 98% |
| Winchester 748 | <<locked>> | 92% | 54,853 psi | 88% | 2972 fps | 99.9% |
| Winchester StaBALL Match | <<locked>> | 94% | 53,693 psi | 87% | 2940 fps | 99.2% |
Start Load - Barrel Length: 24"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 39,189 psi | 63% | 2598 fps | 100% |
| Accurate 2200 | <<locked>> | 80% | 50,299 psi | 81% | 2864 fps | 97.5% |
| Accurate 2230 | <<locked>> | 80% | 51,024 psi | 82% | 2874 fps | 98% |
| Accurate 2460 | <<locked>> | 80% | 42,395 psi | 68% | 2694 fps | 99.4% |
| Accurate 2495 | <<locked>> | 80% | 31,560 psi | 51% | 2493 fps | 99.5% |
| Accurate 2520 | <<locked>> | 80% | 37,536 psi | 61% | 2631 fps | 98.4% |
| Accurate 4064 | <<locked>> | 80% | 29,863 psi | 48% | 2467 fps | 97.2% |
| Accurate LT-30 | <<locked>> | 80% | 47,718 psi | 77% | 2690 fps | 100% |
| Accurate LT-32 | <<locked>> | 80% | 48,095 psi | 78% | 2710 fps | 99.7% |
| ADI AR 2206H | <<locked>> | 82% | 38,319 psi | 62% | 2638 fps | 95.5% |
| ADI AR 2207 | <<locked>> | 80% | 51,663 psi | 83% | 2759 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 41,655 psi | 67% | 2690 fps | 95.6% |
| ADI AR 2219 | <<locked>> | 80% | 47,123 psi | 76% | 2795 fps | 100% |
| ADI Benchmark 8208 | <<locked>> | 80% | 37,739 psi | 61% | 2602 fps | 96.7% |
| Alliant AR-Comp | <<locked>> | 80% | 36,405 psi | 59% | 2621 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 43,323 psi | 70% | 2799 fps | 97.6% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 42,424 psi | 68% | 2818 fps | 95.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 35,621 psi | 57% | 2605 fps | 95.8% |
| Alliant Reloder-10x | <<locked>> | 80% | 44,440 psi | 72% | 2707 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 86% | 38,653 psi | 62% | 2667 fps | 95% |
| Alliant Reloder-17 | <<locked>> | 92% | 38,058 psi | 61% | 2730 fps | 95.6% |
| Baschieri & Pellagri 106 | <<locked>> | 80% | 46,586 psi | 75% | 2684 fps | 100% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 42,453 psi | 68% | 2743 fps | 95.4% |
| Bofors RP3 | <<locked>> | 86% | 35,099 psi | 57% | 2605 fps | 95.7% |
| Hodgdon Benchmark | <<locked>> | 80% | 40,045 psi | 65% | 2608 fps | 97.9% |
| Hodgdon BL-C2 | <<locked>> | 80% | 35,563 psi | 57% | 2605 fps | 96.8% |
| Hodgdon CFE223 | <<locked>> | 80% | 39,349 psi | 63% | 2736 fps | 95.1% |
| Hodgdon H322 | <<locked>> | 80% | 42,989 psi | 69% | 2723 fps | 99.9% |
| Hodgdon H335 | <<locked>> | 80% | 43,569 psi | 70% | 2740 fps | 99.7% |
| Hodgdon H380 | <<locked>> | 92% | 44,280 psi | 71% | 2769 fps | 95.1% |
| Hodgdon H4198 | <<locked>> | 80% | 52,533 psi | 85% | 2785 fps | 100% |
| Hodgdon H4895 | <<locked>> | 80% | 35,955 psi | 58% | 2592 fps | 95.4% |
| Hodgdon Hybrid 100V | <<locked>> | 98% | 36,680 psi | 59% | 2635 fps | 95.1% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 34,403 psi | 55% | 2605 fps | 95.2% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,338 psi | 41% | 1572 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 37,246 psi | 60% | 2605 fps | 95.7% |
| IMR 3031 | <<locked>> | 80% | 34,853 psi | 56% | 2612 fps | 99.5% |
| IMR 4064 | <<locked>> | 86% | 38,682 psi | 62% | 2621 fps | 95% |
| IMR 4198 | <<locked>> | 80% | 45,078 psi | 73% | 2674 fps | 100% |
| IMR 4895 | <<locked>> | 84% | 37,130 psi | 60% | 2648 fps | 95.2% |
| IMR 8208 XBR | <<locked>> | 80% | 37,739 psi | 61% | 2602 fps | 96.7% |
| Lovex D073.4 | <<locked>> | 80% | 51,343 psi | 83% | 2854 fps | 99.9% |
| Lovex D073.5 | <<locked>> | 80% | 42,264 psi | 68% | 2694 fps | 98.7% |
| Lovex D073.6 | <<locked>> | 80% | 33,823 psi | 55% | 2559 fps | 97.4% |
| Lovex S060 | <<locked>> | 80% | 37,043 psi | 60% | 2539 fps | 95.1% |
| Lovex S062 | <<locked>> | 82% | 33,823 psi | 55% | 2526 fps | 95.6% |
| Norma 200 | <<locked>> | 80% | 50,082 psi | 81% | 2772 fps | 100% |
| Norma 201 | <<locked>> | 80% | 35,201 psi | 57% | 2543 fps | 96% |
| Norma 202 | <<locked>> | 80% | 35,230 psi | 57% | 2566 fps | 98.4% |
| Norma 203B | <<locked>> | 86% | 37,898 psi | 61% | 2654 fps | 95.4% |
| Ramshot Big Game | <<locked>> | 88% | 40,480 psi | 65% | 2726 fps | 95.9% |
| Ramshot TAC | <<locked>> | 88% | 49,298 psi | 80% | 2818 fps | 95.6% |
| Ramshot Wild Boar | <<locked>> | 82% | 39,175 psi | 63% | 2667 fps | 95.7% |
| Ramshot X-Terminator | <<locked>> | 80% | 41,089 psi | 66% | 2651 fps | 96.1% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,527 psi | 41% | 1611 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 42,496 psi | 69% | 2700 fps | 99% |
| ReloadSwiss RS 50 | <<locked>> | 96% | 51,735 psi | 83% | 2867 fps | 95% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 40,248 psi | 65% | 2769 fps | 95.4% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 31,227 psi | 50% | 2556 fps | 95.2% |
| Rottweil R 901 | <<locked>> | 80% | 38,885 psi | 63% | 2608 fps | 98.9% |
| Rottweil R 902 | <<locked>> | 80% | 33,504 psi | 54% | 2493 fps | 95.4% |
| Rottweil R 903 | <<locked>> | 88% | 34,983 psi | 56% | 2595 fps | 95.3% |
| Shooters World AR Plus | <<locked>> | 80% | 51,343 psi | 83% | 2854 fps | 99.9% |
| Shooters World Match Rifle | <<locked>> | 80% | 33,823 psi | 55% | 2559 fps | 97.4% |
| Shooters World Precision | <<locked>> | 82% | 33,823 psi | 55% | 2526 fps | 95.6% |
| Shooters World Tactical Rifle | <<locked>> | 80% | 44,846 psi | 72% | 2710 fps | 98.1% |
| SNPE Vectan BA6 1/2 | <<locked>> | 80% | 51,692 psi | 83% | 2510 fps | 100% |
| SNPE Vectan SP 10 | <<locked>> | 80% | 47,355 psi | 76% | 2799 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 39,291 psi | 63% | 2710 fps | 95.6% |
| SNPE Vectan SP 3 | <<locked>> | 80% | 45,208 psi | 73% | 2723 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 88% | 46,905 psi | 76% | 2785 fps | 95.6% |
| SNPE Vectan SP 9 | <<locked>> | 84% | 39,276 psi | 63% | 2657 fps | 95.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 37,101 psi | 60% | 2526 fps | 98.7% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 30,269 psi | 49% | 2385 fps | 97.9% |
| Somchem S321 | <<locked>> | 80% | 40,553 psi | 65% | 2684 fps | 97.8% |
| Somchem S335 | <<locked>> | 80% | 36,376 psi | 59% | 2526 fps | 99.2% |
| Somchem S341 | <<locked>> | 82% | 37,666 psi | 61% | 2612 fps | 95.1% |
| Somchem S355 | <<locked>> | 88% | 36,390 psi | 59% | 2608 fps | 95.5% |
| Somchem S365 | <<locked>> | 96% | 33,547 psi | 54% | 2625 fps | 95.6% |
| Vihtavuori N120 | <<locked>> | 80% | 51,590 psi | 83% | 2710 fps | 100% |
| Vihtavuori N130 | <<locked>> | 80% | 42,148 psi | 68% | 2615 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 37,086 psi | 60% | 2533 fps | 99.9% |
| Vihtavuori N135 | <<locked>> | 80% | 32,242 psi | 52% | 2500 fps | 99.6% |
| Vihtavuori N140 | <<locked>> | 80% | 33,083 psi | 53% | 2497 fps | 98.1% |
| Vihtavuori N150 | <<locked>> | 86% | 32,445 psi | 52% | 2493 fps | 95.7% |
| Vihtavuori N530 | <<locked>> | 80% | 37,811 psi | 61% | 2602 fps | 96.9% |
| Vihtavuori N540 | <<locked>> | 80% | 31,966 psi | 52% | 2480 fps | 97.3% |
| Winchester 6.5 StaBALL | <<locked>> | 94% | 38,392 psi | 62% | 2628 fps | 95.8% |
| Winchester 748 | <<locked>> | 80% | 36,419 psi | 59% | 2635 fps | 97.3% |
| Winchester StaBALL Match | <<locked>> | 82% | 35,868 psi | 58% | 2602 fps | 95.4% |
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 115 powders for .25 GT loaded with the .257 | 100gr | Sierra MatchKing. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,071 fps; across all powders the maximum-charge window runs from 1,762 fps to 3,071 fps. Accurate 4350 gives the best case fill at 100 %, and 115 of the 115 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (427 MPa), the top charges use 51–90 %, leaving at least 10 % headroom. The 100.0 gr projectile in 0.257" calls for a 1:10.5 twist; slower twists will usually not stabilise this weight. Accurate 4350, Alliant Reloder- TS 15.5, Alliant Reloder-16 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. As outliers, Accurate 2700, Bofors RP7, Hodgdon H414 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.