Load Specifications
Bullet Manufacturer:Sierra
Bullet Weight:135 gr
Bullet Diameter:0.257"
Bullet Length:<<locked>>
Caliber:.255 GS load data
Case Length (l3):2.165"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:62 Grains of Water
Primer Size:Large Rifle (LR)
Barrel Length:24"
Max. allowed Pressure:63,817 psi
Recommended Twist Rate:1:8.0
Load data in caliber .255 GS with .257 | 135gr | Sierra Tipped MatchKing bullet and 189 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 Norma MRP.
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 2495 | <<locked>> | 82% | 56,521 psi | 89% | 2641 fps | 100% |
| Accurate 2495 | <<locked>> | 82% | 57,072 psi | 89% | 2651 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 57,450 psi | 90% | 2720 fps | 99.4% |
| Accurate 2700 | <<locked>> | 82% | 54,331 psi | 85% | 2677 fps | 99.1% |
| Accurate 3100ᴾ | <<locked>> | 100% | 55,550 psi | 87% | 2769 fps | 99.9% |
| Accurate 3100ᴾ | <<locked>> | 100% | 55,927 psi | 88% | 2776 fps | 100% |
| Accurate 4064 | <<locked>> | 84% | 57,116 psi | 90% | 2700 fps | 100% |
| Accurate 4064 | <<locked>> | 84% | 57,290 psi | 90% | 2703 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 54,259 psi | 85% | 2762 fps | 100% |
| Accurate 4350 | <<locked>> | 90% | 54,752 psi | 86% | 2772 fps | 100% |
| Accurate High Country | <<locked>> | 98% | 56,797 psi | 89% | 2913 fps | 98.5% |
| Accurate High Country | <<locked>> | 98% | 57,580 psi | 90% | 2927 fps | 98.6% |
| Accurate MAGPRO | <<locked>> | 98% | 54,085 psi | 85% | 2854 fps | 96.8% |
| Accurate MAGPRO | <<locked>> | 98% | 54,491 psi | 85% | 2864 fps | 96.9% |
| ADI AR 2208 | <<locked>> | 86% | 56,811 psi | 89% | 2733 fps | 100% |
| ADI AR 2208 | <<locked>> | 86% | 57,276 psi | 90% | 2740 fps | 100% |
| ADI AR 2209 | <<locked>> | 96% | 54,868 psi | 86% | 2805 fps | 98.8% |
| ADI AR 2209 | <<locked>> | 96% | 55,274 psi | 87% | 2812 fps | 98.8% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 56,420 psi | 88% | 2861 fps | 98% |
| ADI AR 2213ᴾ | <<locked>> | 100% | 56,782 psi | 89% | 2871 fps | 98.2% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 36,448 psi | 57% | 2536 fps | 96.1% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 56,420 psi | 88% | 2854 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 82% | 56,913 psi | 89% | 2864 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 55,172 psi | 86% | 2805 fps | 98.8% |
| Alliant Power Pro Varmint | <<locked>> | 96% | 55,579 psi | 87% | 2812 fps | 98.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 86% | 57,609 psi | 90% | 2753 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 54,491 psi | 85% | 2710 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 54,505 psi | 85% | 2730 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 82% | 54,636 psi | 86% | 2733 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 55,013 psi | 86% | 2815 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 92% | 55,477 psi | 87% | 2825 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 56,202 psi | 88% | 2835 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 88% | 56,710 psi | 89% | 2844 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 96% | 54,433 psi | 85% | 2795 fps | 98.8% |
| Alliant Reloder-19 | <<locked>> | 96% | 54,824 psi | 86% | 2805 fps | 98.8% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 55,477 psi | 87% | 2858 fps | 99% |
| Alliant Reloder-22ᴾ | <<locked>> | 100% | 55,840 psi | 88% | 2864 fps | 99.1% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 52,417 psi | 82% | 2785 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 52,837 psi | 83% | 2792 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 45,556 psi | 71% | 2723 fps | 99.7% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 45,876 psi | 72% | 2730 fps | 99.8% |
| Alliant Reloder-26 | <<locked>> | 98% | 56,072 psi | 88% | 2920 fps | 100% |
| Alliant Reloder-26 | <<locked>> | 98% | 56,942 psi | 89% | 2933 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 50,676 psi | 79% | 2782 fps | 98.2% |
| Bofors RP15ᴾ | <<locked>> | 100% | 51,053 psi | 80% | 2789 fps | 98.3% |
| Bofors RP3 | <<locked>> | 84% | 55,129 psi | 86% | 2723 fps | 100% |
| Bofors RP3 | <<locked>> | 84% | 55,593 psi | 87% | 2730 fps | 100% |
| Bofors RP5ᴾ | <<locked>> | 100% | 55,477 psi | 87% | 2858 fps | 99% |
| Bofors RP5ᴾ | <<locked>> | 100% | 55,840 psi | 88% | 2864 fps | 99.1% |
| Bofors RP7 | <<locked>> | 88% | 54,404 psi | 85% | 2713 fps | 99.3% |
| Bofors RP7 | <<locked>> | 88% | 54,824 psi | 86% | 2723 fps | 99.3% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 45,078 psi | 71% | 2657 fps | 96.3% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 45,353 psi | 71% | 2667 fps | 96.5% |
| Hodgdon H380 | <<locked>> | 84% | 55,230 psi | 87% | 2736 fps | 100% |
| Hodgdon H380 | <<locked>> | 84% | 55,724 psi | 87% | 2746 fps | 100% |
| Hodgdon H414 | <<locked>> | 90% | 56,231 psi | 88% | 2812 fps | 99.7% |
| Hodgdon H414 | <<locked>> | 90% | 56,652 psi | 89% | 2822 fps | 99.8% |
| Hodgdon H4350 | <<locked>> | 88% | 56,057 psi | 88% | 2776 fps | 99.1% |
| Hodgdon H4350 | <<locked>> | 88% | 56,144 psi | 88% | 2779 fps | 99.1% |
| Hodgdon H4831 | <<locked>> | 98% | 56,478 psi | 89% | 2802 fps | 97.4% |
| Hodgdon H4831 | <<locked>> | 98% | 56,840 psi | 89% | 2812 fps | 97.5% |
| Hodgdon H4831 SC | <<locked>> | 98% | 55,361 psi | 87% | 2785 fps | 97.2% |
| Hodgdon H4831 SC | <<locked>> | 98% | 55,724 psi | 87% | 2795 fps | 97.4% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 55,187 psi | 86% | 2740 fps | 100% |
| Hodgdon Hybrid 100V | <<locked>> | 94% | 55,608 psi | 87% | 2746 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 56,840 psi | 89% | 2772 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 56,956 psi | 89% | 2776 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 44,498 psi | 70% | 2759 fps | 97.8% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 44,831 psi | 70% | 2766 fps | 97.9% |
| Hodgdon Superformance | <<locked>> | 90% | 56,420 psi | 88% | 2851 fps | 99.7% |
| Hodgdon Superformance | <<locked>> | 90% | 56,811 psi | 89% | 2858 fps | 99.7% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,593 psi | 57% | 1690 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,608 psi | 57% | 1690 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 57,392 psi | 90% | 2736 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 57,522 psi | 90% | 2740 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 56,492 psi | 89% | 2717 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 56,550 psi | 89% | 2720 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 82% | 55,405 psi | 87% | 2703 fps | 99.6% |
| IMR 4166 Enduron | <<locked>> | 82% | 55,492 psi | 87% | 2707 fps | 99.6% |
| IMR 4350 | <<locked>> | 92% | 55,390 psi | 87% | 2746 fps | 99.4% |
| IMR 4350 | <<locked>> | 92% | 55,796 psi | 87% | 2753 fps | 99.5% |
| IMR 4451 Enduron | <<locked>> | 88% | 56,043 psi | 88% | 2740 fps | 99.6% |
| IMR 4451 Enduron | <<locked>> | 88% | 56,434 psi | 88% | 2746 fps | 99.7% |
| IMR 4831 | <<locked>> | 92% | 54,781 psi | 86% | 2756 fps | 100% |
| IMR 4831 | <<locked>> | 92% | 54,868 psi | 86% | 2759 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 55,927 psi | 88% | 2753 fps | 100% |
| IMR 4895 | <<locked>> | 82% | 56,057 psi | 88% | 2756 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 96% | 54,346 psi | 85% | 2736 fps | 97.2% |
| IMR 4955 Enduron | <<locked>> | 96% | 54,708 psi | 86% | 2743 fps | 97.3% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 53,911 psi | 84% | 2835 fps | 97.7% |
| IMR 7828 SSCᴾ | <<locked>> | 100% | 54,244 psi | 85% | 2844 fps | 97.8% |
| Lovex S060 | <<locked>> | 82% | 57,711 psi | 90% | 2697 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 56,420 psi | 88% | 2703 fps | 100% |
| Lovex S062 | <<locked>> | 84% | 56,898 psi | 89% | 2713 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 56,101 psi | 88% | 2733 fps | 100% |
| Lovex S065 | <<locked>> | 90% | 56,550 psi | 89% | 2743 fps | 100% |
| Lovex S070 | <<locked>> | 92% | 57,667 psi | 90% | 2779 fps | 99.8% |
| Lovex S070 | <<locked>> | 92% | 57,740 psi | 90% | 2782 fps | 99.9% |
| Lovex S071ᴾ | <<locked>> | 100% | 46,354 psi | 73% | 2628 fps | 99.3% |
| Lovex S071ᴾ | <<locked>> | 100% | 46,775 psi | 73% | 2638 fps | 99.3% |
| Norma 203B | <<locked>> | 84% | 57,450 psi | 90% | 2762 fps | 100% |
| Norma 203B | <<locked>> | 84% | 57,551 psi | 90% | 2769 fps | 100% |
| Norma 204 | <<locked>> | 92% | 56,173 psi | 88% | 2799 fps | 98.8% |
| Norma 204 | <<locked>> | 92% | 56,579 psi | 89% | 2808 fps | 98.9% |
| Norma MRP | <<locked>> | 98% | 54,824 psi | 86% | 2877 fps | 99.7% |
| Norma MRP | <<locked>> | 98% | 55,622 psi | 87% | 2890 fps | 99.8% |
| Norma URP | <<locked>> | 92% | 56,565 psi | 89% | 2799 fps | 100% |
| Norma URP | <<locked>> | 92% | 56,681 psi | 89% | 2802 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 54,476 psi | 85% | 2740 fps | 100% |
| Ramshot Big Game | <<locked>> | 82% | 54,911 psi | 86% | 2746 fps | 100% |
| Ramshot Grandᴾ | <<locked>> | 100% | 53,998 psi | 85% | 2848 fps | 98.1% |
| Ramshot Grandᴾ | <<locked>> | 100% | 54,781 psi | 86% | 2861 fps | 98.2% |
| Ramshot Hunter | <<locked>> | 92% | 55,129 psi | 86% | 2802 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 92% | 55,550 psi | 87% | 2808 fps | 99.9% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 48,211 psi | 76% | 2726 fps | 98.5% |
| Ramshot Magnumᴾ | <<locked>> | 100% | 48,878 psi | 77% | 2740 fps | 98.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,260 psi | 58% | 1726 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,275 psi | 58% | 1729 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 55,259 psi | 87% | 2726 fps | 99.8% |
| ReloadSwiss RS 50 | <<locked>> | 84% | 55,680 psi | 87% | 2736 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 55,753 psi | 87% | 2828 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 86% | 56,260 psi | 88% | 2835 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 54,114 psi | 85% | 2785 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 90% | 54,534 psi | 85% | 2792 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 56,275 psi | 88% | 2867 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 92% | 56,681 psi | 89% | 2874 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 44,324 psi | 69% | 2749 fps | 98.7% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 44,860 psi | 70% | 2762 fps | 98.8% |
| Rottweil R 902 | <<locked>> | 82% | 55,274 psi | 87% | 2671 fps | 100% |
| Rottweil R 902 | <<locked>> | 82% | 55,405 psi | 87% | 2677 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 55,347 psi | 87% | 2720 fps | 100% |
| Rottweil R 903 | <<locked>> | 86% | 55,448 psi | 87% | 2723 fps | 100% |
| Rottweil R 904 | <<locked>> | 96% | 56,565 psi | 89% | 2776 fps | 98.1% |
| Rottweil R 904 | <<locked>> | 96% | 56,971 psi | 89% | 2785 fps | 98.2% |
| Rottweil R 905 | <<locked>> | 98% | 57,290 psi | 90% | 2835 fps | 99.2% |
| Rottweil R 905 | <<locked>> | 98% | 57,711 psi | 90% | 2844 fps | 99.2% |
| Rottweil R 907 | <<locked>> | 88% | 54,404 psi | 85% | 2713 fps | 99.3% |
| Rottweil R 907 | <<locked>> | 88% | 54,824 psi | 86% | 2723 fps | 99.3% |
| Shooters World Long Rifle | <<locked>> | 90% | 56,101 psi | 88% | 2733 fps | 100% |
| Shooters World Long Rifle | <<locked>> | 90% | 56,550 psi | 89% | 2743 fps | 100% |
| Shooters World Precision | <<locked>> | 84% | 56,420 psi | 88% | 2703 fps | 100% |
| Shooters World Precision | <<locked>> | 84% | 56,898 psi | 89% | 2713 fps | 100% |
| Shooters World SW4350 | <<locked>> | 92% | 57,667 psi | 90% | 2779 fps | 99.8% |
| Shooters World SW4350 | <<locked>> | 92% | 57,740 psi | 90% | 2782 fps | 99.9% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 56,768 psi | 89% | 2776 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 57,232 psi | 90% | 2785 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 57,682 psi | 90% | 2749 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 56,217 psi | 88% | 2605 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 86% | 56,333 psi | 88% | 2608 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 55,912 psi | 88% | 2690 fps | 99.6% |
| SNPE Vectan Tubal 7000 | <<locked>> | 90% | 55,970 psi | 88% | 2694 fps | 99.7% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 56,811 psi | 89% | 2831 fps | 99.1% |
| SNPE Vectan Tubal 8000 | <<locked>> | 98% | 57,217 psi | 90% | 2841 fps | 99.2% |
| Somchem S355 | <<locked>> | 86% | 55,056 psi | 86% | 2713 fps | 100% |
| Somchem S355 | <<locked>> | 86% | 55,564 psi | 87% | 2723 fps | 100% |
| Somchem S361 | <<locked>> | 94% | 54,781 psi | 86% | 2717 fps | 97% |
| Somchem S361 | <<locked>> | 94% | 55,100 psi | 86% | 2726 fps | 97.1% |
| Somchem S365 | <<locked>> | 94% | 56,043 psi | 88% | 2799 fps | 100% |
| Somchem S365 | <<locked>> | 94% | 56,478 psi | 89% | 2805 fps | 100% |
| Somchem S385 | <<locked>> | 96% | 54,331 psi | 85% | 2759 fps | 99.3% |
| Somchem S385 | <<locked>> | 96% | 54,723 psi | 86% | 2766 fps | 99.4% |
| Vihtavuori N135 | <<locked>> | 82% | 55,477 psi | 87% | 2628 fps | 100% |
| Vihtavuori N135 | <<locked>> | 82% | 56,043 psi | 88% | 2635 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 55,840 psi | 88% | 2648 fps | 100% |
| Vihtavuori N140 | <<locked>> | 82% | 55,970 psi | 88% | 2648 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 56,246 psi | 88% | 2687 fps | 100% |
| Vihtavuori N150 | <<locked>> | 88% | 56,724 psi | 89% | 2694 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 55,027 psi | 86% | 2740 fps | 100% |
| Vihtavuori N160 | <<locked>> | 90% | 55,463 psi | 87% | 2749 fps | 100% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 53,403 psi | 84% | 2733 fps | 98.9% |
| Vihtavuori N165ᴾ | <<locked>> | 100% | 53,809 psi | 84% | 2740 fps | 99% |
| Vihtavuori N540 | <<locked>> | 84% | 57,145 psi | 90% | 2687 fps | 100% |
| Vihtavuori N540 | <<locked>> | 84% | 57,580 psi | 90% | 2694 fps | 100% |
| Vihtavuori N550 | <<locked>> | 92% | 57,537 psi | 90% | 2795 fps | 100% |
| Vihtavuori N550 | <<locked>> | 90% | 54,360 psi | 85% | 2753 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 54,795 psi | 86% | 2808 fps | 100% |
| Vihtavuori N555 | <<locked>> | 98% | 55,259 psi | 87% | 2815 fps | 100% |
| Vihtavuori N560 | <<locked>> | 98% | 55,085 psi | 86% | 2867 fps | 97.6% |
| Vihtavuori N560 | <<locked>> | 98% | 55,796 psi | 87% | 2884 fps | 97.7% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 47,297 psi | 74% | 2726 fps | 96.1% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 47,616 psi | 75% | 2736 fps | 96.3% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 54,360 psi | 85% | 2707 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 54,752 psi | 86% | 2713 fps | 100% |
| Winchester 760 | <<locked>> | 90% | 56,565 psi | 89% | 2818 fps | 99.8% |
| Winchester 760 | <<locked>> | 90% | 57,014 psi | 89% | 2825 fps | 99.8% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 47,442 psi | 74% | 2848 fps | 100% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 47,906 psi | 75% | 2854 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 98% | 54,476 psi | 85% | 2756 fps | 98.6% |
| Winchester Supreme 780 | <<locked>> | 98% | 54,824 psi | 86% | 2762 fps | 98.7% |
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% | 53,214 psi | 83% | 2602 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 53,374 psi | 84% | 2605 fps | 100% |
| Accurate 2700 | <<locked>> | 80% | 50,531 psi | 79% | 2615 fps | 98.6% |
| Accurate 2700 | <<locked>> | 80% | 50,981 psi | 80% | 2625 fps | 98.7% |
| Accurate 3100 | <<locked>> | 82% | 30,385 psi | 48% | 2297 fps | 95% |
| Accurate 3100 | <<locked>> | 82% | 30,501 psi | 48% | 2303 fps | 95.1% |
| Accurate 4064 | <<locked>> | 80% | 50,459 psi | 79% | 2608 fps | 100% |
| Accurate 4064 | <<locked>> | 80% | 50,618 psi | 79% | 2612 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 38,551 psi | 60% | 2497 fps | 99.1% |
| Accurate 4350 | <<locked>> | 80% | 38,957 psi | 61% | 2507 fps | 99.2% |
| Accurate High Country | 46 gr | 90% | 43,178 psi | 68% | 2677 fps | 95.5% |
| Accurate High Country | 46 gr | 90% | 43,584 psi | 68% | 2687 fps | 95.7% |
| Accurate MAGPRO | <<locked>> | 94% | 46,876 psi | 73% | 2733 fps | 95% |
| Accurate MAGPRO | <<locked>> | 94% | 47,224 psi | 74% | 2743 fps | 95.2% |
| ADI AR 2208 | <<locked>> | 80% | 47,398 psi | 74% | 2589 fps | 100% |
| ADI AR 2208 | <<locked>> | 80% | 47,529 psi | 74% | 2592 fps | 100% |
| ADI AR 2209 | <<locked>> | 86% | 39,769 psi | 62% | 2530 fps | 95.3% |
| ADI AR 2209 | <<locked>> | 86% | 40,103 psi | 63% | 2539 fps | 95.5% |
| ADI AR 2213 | <<locked>> | 94% | 46,064 psi | 72% | 2684 fps | 95.7% |
| ADI AR 2213 | <<locked>> | 92% | 43,410 psi | 68% | 2635 fps | 95% |
| ADI AR 2225 | <<locked>> | 98% | 34,214 psi | 54% | 2477 fps | 95% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 52,692 psi | 83% | 2802 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 52,823 psi | 83% | 2805 fps | 100% |
| Alliant Power Pro Varmint | <<locked>> | 86% | 39,856 psi | 62% | 2533 fps | 95.4% |
| Alliant Power Pro Varmint | <<locked>> | 86% | 40,219 psi | 63% | 2543 fps | 95.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 47,979 psi | 75% | 2612 fps | 100% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 48,153 psi | 75% | 2615 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 51,097 psi | 80% | 2677 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 80% | 51,576 psi | 81% | 2687 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,449 psi | 59% | 2503 fps | 99.2% |
| Alliant Reloder-16 | <<locked>> | 80% | 37,608 psi | 59% | 2510 fps | 99.2% |
| Alliant Reloder-17 | <<locked>> | 80% | 42,453 psi | 67% | 2621 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 80% | 42,873 psi | 67% | 2631 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 39,436 psi | 62% | 2523 fps | 95.4% |
| Alliant Reloder-19 | <<locked>> | 86% | 39,798 psi | 62% | 2533 fps | 95.5% |
| Alliant Reloder-22 | <<locked>> | 90% | 39,827 psi | 62% | 2579 fps | 95.7% |
| Alliant Reloder-22 | <<locked>> | 90% | 39,914 psi | 63% | 2582 fps | 95.8% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,586 psi | 43% | 2277 fps | 97.5% |
| Alliant Reloder-23 | <<locked>> | 80% | 27,717 psi | 43% | 2283 fps | 97.6% |
| Alliant Reloder-25 | <<locked>> | 88% | 31,198 psi | 49% | 2392 fps | 95.8% |
| Alliant Reloder-25 | <<locked>> | 88% | 31,256 psi | 49% | 2395 fps | 95.9% |
| Alliant Reloder-26 | 42.1 gr | 80% | 29,298 psi | 46% | 2379 fps | 95.8% |
| Alliant Reloder-26 | 42.1 gr | 80% | 29,588 psi | 46% | 2392 fps | 96% |
| Bofors RP15 | <<locked>> | 92% | 39,305 psi | 62% | 2566 fps | 95.3% |
| Bofors RP15 | <<locked>> | 92% | 39,392 psi | 62% | 2569 fps | 95.4% |
| Bofors RP3 | <<locked>> | 80% | 48,225 psi | 76% | 2621 fps | 100% |
| Bofors RP3 | <<locked>> | 80% | 48,675 psi | 76% | 2631 fps | 100% |
| Bofors RP5 | <<locked>> | 90% | 39,827 psi | 62% | 2579 fps | 95.7% |
| Bofors RP5 | <<locked>> | 90% | 39,914 psi | 63% | 2582 fps | 95.8% |
| Bofors RP7 | <<locked>> | 80% | 42,467 psi | 67% | 2507 fps | 97.3% |
| Bofors RP7 | <<locked>> | 80% | 42,569 psi | 67% | 2510 fps | 97.4% |
| Hodgdon H1000 | <<locked>> | 98% | 42,105 psi | 66% | 2598 fps | 95.3% |
| Hodgdon H1000 | <<locked>> | 98% | 42,409 psi | 66% | 2608 fps | 95.5% |
| Hodgdon H380 | <<locked>> | 80% | 48,776 psi | 76% | 2638 fps | 99.9% |
| Hodgdon H380 | <<locked>> | 80% | 48,892 psi | 77% | 2641 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 80% | 40,364 psi | 63% | 2539 fps | 97.4% |
| Hodgdon H414 | <<locked>> | 80% | 40,770 psi | 64% | 2549 fps | 97.5% |
| Hodgdon H4350 | <<locked>> | 80% | 43,221 psi | 68% | 2556 fps | 96.8% |
| Hodgdon H4350 | <<locked>> | 80% | 43,627 psi | 68% | 2566 fps | 97% |
| Hodgdon H4831 | <<locked>> | 92% | 46,108 psi | 72% | 2635 fps | 95.1% |
| Hodgdon H4831 | <<locked>> | 92% | 46,470 psi | 73% | 2641 fps | 95.2% |
| Hodgdon H4831 SC | <<locked>> | 94% | 48,298 psi | 76% | 2674 fps | 95.7% |
| Hodgdon H4831 SC | <<locked>> | 92% | 45,513 psi | 71% | 2625 fps | 95% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 34,940 psi | 55% | 2398 fps | 99.5% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 35,331 psi | 55% | 2408 fps | 99.6% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 52,924 psi | 83% | 2717 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 53,374 psi | 84% | 2726 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 96% | 39,030 psi | 61% | 2631 fps | 95.8% |
| Hodgdon Retumbo | <<locked>> | 94% | 37,101 psi | 58% | 2585 fps | 95% |
| Hodgdon Superformance | <<locked>> | 80% | 39,218 psi | 61% | 2549 fps | 96.7% |
| Hodgdon Superformance | <<locked>> | 80% | 39,552 psi | 62% | 2559 fps | 96.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,311 psi | 43% | 1506 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,383 psi | 43% | 1509 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 53,809 psi | 84% | 2684 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 53,925 psi | 85% | 2687 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 49,850 psi | 78% | 2618 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 50,009 psi | 78% | 2625 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 51,982 psi | 81% | 2651 fps | 99.3% |
| IMR 4166 Enduron | <<locked>> | 80% | 52,098 psi | 82% | 2654 fps | 99.3% |
| IMR 4350 | <<locked>> | 80% | 38,058 psi | 60% | 2438 fps | 96.1% |
| IMR 4350 | <<locked>> | 80% | 38,174 psi | 60% | 2444 fps | 96.2% |
| IMR 4451 Enduron | <<locked>> | 80% | 43,714 psi | 69% | 2533 fps | 98% |
| IMR 4451 Enduron | <<locked>> | 80% | 44,106 psi | 69% | 2543 fps | 98.1% |
| IMR 4831 | <<locked>> | 80% | 37,115 psi | 58% | 2451 fps | 98.8% |
| IMR 4831 | <<locked>> | 80% | 37,260 psi | 58% | 2457 fps | 98.9% |
| IMR 4895 | <<locked>> | 80% | 52,388 psi | 82% | 2700 fps | 100% |
| IMR 4895 | <<locked>> | 80% | 52,866 psi | 83% | 2710 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 90% | 45,092 psi | 71% | 2579 fps | 95% |
| IMR 4955 Enduron | <<locked>> | 90% | 45,440 psi | 71% | 2589 fps | 95.2% |
| IMR 7828 SSC | <<locked>> | 94% | 43,990 psi | 69% | 2657 fps | 95.2% |
| IMR 7828 SSC | <<locked>> | 94% | 44,309 psi | 69% | 2667 fps | 95.4% |
| Lovex S060 | <<locked>> | 80% | 54,491 psi | 85% | 2651 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 50,212 psi | 79% | 2618 fps | 100% |
| Lovex S062 | <<locked>> | 80% | 50,328 psi | 79% | 2621 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 41,481 psi | 65% | 2490 fps | 98.7% |
| Lovex S065 | <<locked>> | 80% | 41,611 psi | 65% | 2493 fps | 98.7% |
| Lovex S070 | <<locked>> | 80% | 39,668 psi | 62% | 2470 fps | 97.3% |
| Lovex S070 | <<locked>> | 80% | 39,798 psi | 62% | 2477 fps | 97.4% |
| Lovex S071 | <<locked>> | 88% | 31,691 psi | 50% | 2333 fps | 95.6% |
| Lovex S071 | <<locked>> | 88% | 31,792 psi | 50% | 2336 fps | 95.6% |
| Norma 203B | <<locked>> | 80% | 50,459 psi | 79% | 2664 fps | 100% |
| Norma 203B | <<locked>> | 80% | 50,937 psi | 80% | 2674 fps | 100% |
| Norma 204 | <<locked>> | 82% | 40,161 psi | 63% | 2520 fps | 95.3% |
| Norma 204 | <<locked>> | 82% | 40,248 psi | 63% | 2523 fps | 95.4% |
| Norma MRP | 42.9 gr | 84% | 33,895 psi | 53% | 2467 fps | 95% |
| Norma MRP | 42.9 gr | 84% | 34,200 psi | 54% | 2477 fps | 95.1% |
| Norma URP | <<locked>> | 80% | 38,334 psi | 60% | 2490 fps | 98.9% |
| Norma URP | <<locked>> | 80% | 38,450 psi | 60% | 2493 fps | 99% |
| Ramshot Big Game | <<locked>> | 80% | 51,053 psi | 80% | 2690 fps | 100% |
| Ramshot Big Game | <<locked>> | 80% | 51,169 psi | 80% | 2694 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 43,729 psi | 69% | 2664 fps | 95.6% |
| Ramshot Grand | <<locked>> | 94% | 44,063 psi | 69% | 2674 fps | 95.7% |
| Ramshot Hunter | <<locked>> | 80% | 37,144 psi | 58% | 2477 fps | 97.3% |
| Ramshot Hunter | <<locked>> | 80% | 37,260 psi | 58% | 2484 fps | 97.4% |
| Ramshot Magnum | <<locked>> | 92% | 36,158 psi | 57% | 2484 fps | 95% |
| Ramshot Magnum | <<locked>> | 92% | 36,448 psi | 57% | 2493 fps | 95.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,963 psi | 44% | 1545 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 28,036 psi | 44% | 1549 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 48,617 psi | 76% | 2621 fps | 99.3% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 48,718 psi | 76% | 2625 fps | 99.3% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 45,107 psi | 71% | 2667 fps | 100% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 45,542 psi | 71% | 2677 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 38,363 psi | 60% | 2513 fps | 98.8% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 38,479 psi | 60% | 2520 fps | 98.9% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 37,188 psi | 58% | 2523 fps | 98.4% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 37,275 psi | 58% | 2530 fps | 98.4% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 36,042 psi | 56% | 2556 fps | 95.8% |
| ReloadSwiss RS 76 | <<locked>> | 94% | 36,274 psi | 57% | 2566 fps | 95.9% |
| Rottweil R 902 | <<locked>> | 80% | 51,793 psi | 81% | 2625 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 52,272 psi | 82% | 2631 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 45,571 psi | 71% | 2572 fps | 100% |
| Rottweil R 903 | <<locked>> | 80% | 45,716 psi | 72% | 2579 fps | 100% |
| Rottweil R 904 | <<locked>> | 88% | 44,048 psi | 69% | 2566 fps | 95.4% |
| Rottweil R 904 | <<locked>> | 88% | 44,411 psi | 70% | 2575 fps | 95.6% |
| Rottweil R 905 | <<locked>> | 86% | 38,566 psi | 60% | 2510 fps | 95.3% |
| Rottweil R 905 | <<locked>> | 86% | 38,928 psi | 61% | 2520 fps | 95.5% |
| Rottweil R 907 | <<locked>> | 80% | 42,467 psi | 67% | 2507 fps | 97.3% |
| Rottweil R 907 | <<locked>> | 80% | 42,569 psi | 67% | 2510 fps | 97.4% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,481 psi | 65% | 2490 fps | 98.7% |
| Shooters World Long Rifle | <<locked>> | 80% | 41,611 psi | 65% | 2493 fps | 98.7% |
| Shooters World Precision | <<locked>> | 80% | 50,212 psi | 79% | 2618 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 50,328 psi | 79% | 2621 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 39,668 psi | 62% | 2470 fps | 97.3% |
| Shooters World SW4350 | <<locked>> | 80% | 39,798 psi | 62% | 2477 fps | 97.4% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 46,702 psi | 73% | 2628 fps | 100% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 46,818 psi | 73% | 2631 fps | 100% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 54,128 psi | 85% | 2697 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 46,659 psi | 73% | 2477 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 46,818 psi | 73% | 2480 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,480 psi | 63% | 2434 fps | 97.4% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 40,596 psi | 64% | 2438 fps | 97.5% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 38,203 psi | 60% | 2503 fps | 95.1% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 38,566 psi | 60% | 2513 fps | 95.3% |
| Somchem S355 | <<locked>> | 80% | 45,905 psi | 72% | 2572 fps | 100% |
| Somchem S355 | <<locked>> | 80% | 46,006 psi | 72% | 2575 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 47,935 psi | 75% | 2608 fps | 95.5% |
| Somchem S361 | <<locked>> | 90% | 48,254 psi | 76% | 2615 fps | 95.7% |
| Somchem S365 | <<locked>> | 80% | 34,751 psi | 54% | 2451 fps | 100% |
| Somchem S365 | <<locked>> | 80% | 34,925 psi | 55% | 2454 fps | 100% |
| Somchem S385 | <<locked>> | 84% | 36,767 psi | 58% | 2444 fps | 95.6% |
| Somchem S385 | <<locked>> | 84% | 37,115 psi | 58% | 2451 fps | 95.8% |
| Vihtavuori N135 | <<locked>> | 80% | 52,214 psi | 82% | 2585 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 52,417 psi | 82% | 2589 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 52,344 psi | 82% | 2602 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 52,460 psi | 82% | 2605 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 43,743 psi | 69% | 2503 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 43,874 psi | 69% | 2507 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 39,653 psi | 62% | 2487 fps | 99.1% |
| Vihtavuori N160 | <<locked>> | 80% | 40,059 psi | 63% | 2497 fps | 99.2% |
| Vihtavuori N165 | <<locked>> | 90% | 38,653 psi | 61% | 2477 fps | 95.8% |
| Vihtavuori N165 | <<locked>> | 88% | 36,492 psi | 57% | 2431 fps | 95.1% |
| Vihtavuori N540 | <<locked>> | 80% | 50,647 psi | 79% | 2598 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 50,763 psi | 80% | 2602 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 39,218 psi | 61% | 2490 fps | 98.9% |
| Vihtavuori N550 | <<locked>> | 80% | 39,349 psi | 62% | 2497 fps | 99% |
| Vihtavuori N555 | <<locked>> | 80% | 30,560 psi | 48% | 2352 fps | 97.5% |
| Vihtavuori N555 | <<locked>> | 80% | 30,705 psi | 48% | 2356 fps | 97.6% |
| Vihtavuori N560 | <<locked>> | 92% | 45,049 psi | 71% | 2694 fps | 95.1% |
| Vihtavuori N560 | <<locked>> | 92% | 45,397 psi | 71% | 2703 fps | 95.3% |
| Vihtavuori N565 | <<locked>> | 98% | 44,179 psi | 69% | 2671 fps | 95.3% |
| Vihtavuori N565 | <<locked>> | 98% | 44,498 psi | 70% | 2677 fps | 95.4% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 38,769 psi | 61% | 2457 fps | 100% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 38,841 psi | 61% | 2461 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 40,640 psi | 64% | 2546 fps | 97.5% |
| Winchester 760 | <<locked>> | 80% | 40,770 psi | 64% | 2549 fps | 97.5% |
| Winchester StaBALL HD | <<locked>> | 80% | 24,337 psi | 38% | 2254 fps | 96.5% |
| Winchester StaBALL HD | <<locked>> | 80% | 24,424 psi | 38% | 2260 fps | 96.6% |
| Winchester Supreme 780 | <<locked>> | 88% | 38,522 psi | 60% | 2477 fps | 95% |
| Winchester Supreme 780 | <<locked>> | 88% | 38,870 psi | 61% | 2487 fps | 95.2% |
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 189 powders for .255 GS loaded with the .257 | 135gr | Sierra Tipped MatchKing. Alliant Reloder-26 delivers the highest muzzle velocity at 2,933 fps; across all powders the maximum-charge window runs from 1,690 fps to 2,933 fps. Accurate 3100 gives the best case fill at 100 %, and 189 of the 189 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 57–90 %, leaving at least 10 % headroom. The 135.0 gr projectile in 0.257" calls for a 1:8.0 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate 3100, ADI AR 2213 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, Norma MRP rank at the top here: for .255 GS with the .257 | 135gr | Sierra Tipped MatchKing 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.