Load Specifications
Load data in caliber .255 GS with .257 | 100gr | Nosler Ballistic Tip Hunting bullet and 95 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are ReloadSwiss RS 70, Hodgdon Superformance and ReloadSwiss RS 60.
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% | 54,868 psi | 86% | 3018 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 54,346 psi | 85% | 3048 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 55,767 psi | 87% | 3117 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 56,710 psi | 89% | 3100 fps | 97.2% |
| Accurate 3100ᴾ | <<locked>> | 100% | 45,266 psi | 71% | 2986 fps | 96.6% |
| Accurate 4064 | <<locked>> | 88% | 54,491 psi | 85% | 3100 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 54,592 psi | 86% | 3186 fps | 99.5% |
| ADI AR 2206H | <<locked>> | 86% | 57,609 psi | 90% | 3182 fps | 100% |
| ADI AR 2208 | <<locked>> | 90% | 55,216 psi | 87% | 3127 fps | 99.7% |
| ADI Benchmark 8208 | <<locked>> | 84% | 56,507 psi | 89% | 3130 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 54,244 psi | 85% | 3054 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 53,983 psi | 85% | 3251 fps | 99.7% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 55,825 psi | 87% | 3156 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 56,202 psi | 88% | 3176 fps | 99.8% |
| Alliant Reloder-16 | <<locked>> | 98% | 55,463 psi | 87% | 3248 fps | 99.8% |
| Alliant Reloder-17 | <<locked>> | 94% | 57,188 psi | 90% | 3291 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 42,815 psi | 67% | 3015 fps | 99.2% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 48,573 psi | 76% | 3205 fps | 98.8% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 54,128 psi | 85% | 3140 fps | 99.5% |
| Bofors RP3 | <<locked>> | 90% | 56,449 psi | 88% | 3169 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 56,333 psi | 88% | 3136 fps | 97.3% |
| Hodgdon Benchmark | <<locked>> | 82% | 54,534 psi | 85% | 3054 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 56,246 psi | 88% | 3159 fps | 100% |
| Hodgdon H380 | <<locked>> | 90% | 57,246 psi | 90% | 3186 fps | 99.5% |
| Hodgdon H414 | <<locked>> | 96% | 57,363 psi | 90% | 3241 fps | 98.2% |
| Hodgdon H4350 | <<locked>> | 94% | 57,595 psi | 90% | 3199 fps | 96.9% |
| Hodgdon H4895 | <<locked>> | 84% | 54,766 psi | 86% | 3140 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 55,608 psi | 87% | 3166 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 54,520 psi | 85% | 3169 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 54,259 psi | 85% | 3212 fps | 97.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,679 psi | 56% | 1965 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 55,970 psi | 88% | 3143 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 55,172 psi | 86% | 3127 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 54,694 psi | 86% | 3110 fps | 99.8% |
| IMR 4166 Enduron | <<locked>> | 86% | 54,592 psi | 86% | 3084 fps | 97.5% |
| IMR 4350 | <<locked>> | 98% | 56,913 psi | 89% | 3166 fps | 97.5% |
| IMR 4451 Enduron | <<locked>> | 92% | 54,723 psi | 86% | 3114 fps | 97.5% |
| IMR 4831 | <<locked>> | 98% | 55,085 psi | 86% | 3176 fps | 99.6% |
| IMR 4895 | <<locked>> | 88% | 57,667 psi | 90% | 3212 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 56,507 psi | 89% | 3130 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 54,143 psi | 85% | 3100 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 56,768 psi | 89% | 3104 fps | 100% |
| Lovex S062 | <<locked>> | 88% | 54,679 psi | 86% | 3104 fps | 100% |
| Lovex S065 | <<locked>> | 96% | 57,595 psi | 90% | 3163 fps | 99% |
| Lovex S070 | <<locked>> | 96% | 55,419 psi | 87% | 3146 fps | 97.9% |
| Norma 201 | <<locked>> | 86% | 56,521 psi | 89% | 3127 fps | 100% |
| Norma 202 | <<locked>> | 86% | 57,000 psi | 89% | 3123 fps | 100% |
| Norma 203B | <<locked>> | 88% | 55,419 psi | 87% | 3163 fps | 99.9% |
| Norma MRPᴾ | <<locked>> | 100% | 47,906 psi | 75% | 3150 fps | 96.1% |
| Norma URP | <<locked>> | 98% | 57,159 psi | 90% | 3232 fps | 99.7% |
| Ramshot Big Game | <<locked>> | 88% | 55,999 psi | 88% | 3186 fps | 99.9% |
| Ramshot Hunter | <<locked>> | 98% | 56,014 psi | 88% | 3225 fps | 98.6% |
| Ramshot TAC | <<locked>> | 84% | 56,898 psi | 89% | 3150 fps | 99.1% |
| Ramshot Wild Boar | <<locked>> | 84% | 56,811 psi | 89% | 3169 fps | 100% |
| Ramshot X-Terminator | <<locked>> | 82% | 57,276 psi | 90% | 3130 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,390 psi | 57% | 2014 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 90% | 57,493 psi | 90% | 3163 fps | 98.5% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 56,884 psi | 89% | 3248 fps | 99.9% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 56,753 psi | 89% | 3287 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 54,476 psi | 85% | 3209 fps | 99.4% |
| ReloadSwiss RS 70 | <<locked>> | 98% | 57,711 psi | 90% | 3304 fps | 99.6% |
| Rottweil R 901 | <<locked>> | 84% | 57,145 psi | 90% | 3104 fps | 100% |
| Rottweil R 902 | <<locked>> | 88% | 56,869 psi | 89% | 3123 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 56,318 psi | 88% | 3159 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 56,333 psi | 88% | 3136 fps | 97.3% |
| Shooters World Long Rifle | <<locked>> | 96% | 57,595 psi | 90% | 3163 fps | 99% |
| Shooters World Match Rifle | <<locked>> | 84% | 54,143 psi | 85% | 3100 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 54,679 psi | 86% | 3104 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 55,419 psi | 87% | 3146 fps | 97.9% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 54,404 psi | 85% | 3166 fps | 99.9% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 55,666 psi | 87% | 3127 fps | 99.2% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 56,275 psi | 88% | 3153 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 57,580 psi | 90% | 3058 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 54,839 psi | 86% | 3005 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 54,433 psi | 85% | 3054 fps | 97.5% |
| Somchem S335 | <<locked>> | 86% | 57,232 psi | 90% | 3054 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 55,100 psi | 86% | 3114 fps | 99.9% |
| Somchem S355 | <<locked>> | 92% | 56,434 psi | 88% | 3156 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 55,535 psi | 87% | 3232 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 51,227 psi | 80% | 3094 fps | 96.3% |
| Vihtavuori N130 | <<locked>> | 82% | 57,319 psi | 90% | 3018 fps | 100% |
| Vihtavuori N133 | <<locked>> | 84% | 54,752 psi | 86% | 2995 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 56,913 psi | 89% | 3084 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 54,273 psi | 85% | 3051 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 54,360 psi | 85% | 3077 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 55,927 psi | 88% | 3169 fps | 99.5% |
| Vihtavuori N530 | <<locked>> | 84% | 57,188 psi | 90% | 3130 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 56,014 psi | 88% | 3097 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 55,129 psi | 86% | 3173 fps | 99.4% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 47,514 psi | 74% | 3104 fps | 99.1% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 56,202 psi | 88% | 3143 fps | 100% |
| Winchester 748 | <<locked>> | 84% | 57,319 psi | 90% | 3179 fps | 100% |
| Winchester 760 | <<locked>> | 96% | 57,682 psi | 90% | 3245 fps | 98.2% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 38,508 psi | 60% | 3028 fps | 99.3% |
| Winchester StaBALL Match | <<locked>> | 86% | 56,478 psi | 89% | 3163 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% | 51,503 psi | 81% | 2969 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 44,425 psi | 70% | 2887 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 52,054 psi | 82% | 3058 fps | 100% |
| Accurate 2700 | <<locked>> | 84% | 49,574 psi | 78% | 2976 fps | 95.6% |
| Accurate 3100 | <<locked>> | 98% | 42,032 psi | 66% | 2920 fps | 95.7% |
| Accurate 4064 | <<locked>> | 80% | 42,032 psi | 66% | 2881 fps | 100% |
| Accurate 4350 | <<locked>> | 84% | 35,911 psi | 56% | 2805 fps | 95.5% |
| ADI AR 2206H | <<locked>> | 80% | 47,659 psi | 75% | 3005 fps | 99.3% |
| ADI AR 2208 | <<locked>> | 80% | 40,495 psi | 63% | 2841 fps | 97.6% |
| ADI Benchmark 8208 | <<locked>> | 80% | 49,705 psi | 78% | 3015 fps | 99.9% |
| Alliant AR-Comp | <<locked>> | 80% | 50,720 psi | 79% | 3002 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 43,729 psi | 69% | 3045 fps | 98.3% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 40,582 psi | 64% | 2871 fps | 98.9% |
| Alliant Reloder-15 | <<locked>> | 80% | 43,308 psi | 68% | 2936 fps | 98.3% |
| Alliant Reloder-16 | <<locked>> | 84% | 35,694 psi | 56% | 2822 fps | 95.6% |
| Alliant Reloder-17 | <<locked>> | 80% | 35,230 psi | 55% | 2835 fps | 97.2% |
| Alliant Reloder-23 | <<locked>> | 90% | 31,125 psi | 49% | 2710 fps | 95.3% |
| Alliant Reloder-26 | <<locked>> | 94% | 38,885 psi | 61% | 2982 fps | 96.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 47,297 psi | 74% | 3015 fps | 98.6% |
| Bofors RP3 | <<locked>> | 80% | 40,408 psi | 63% | 2874 fps | 98.9% |
| Bofors RP7 | <<locked>> | 88% | 46,499 psi | 73% | 2956 fps | 95.1% |
| Hodgdon Benchmark | <<locked>> | 80% | 51,314 psi | 80% | 3002 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 49,110 psi | 77% | 3041 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 40,944 psi | 64% | 2874 fps | 96.6% |
| Hodgdon H414 | <<locked>> | 88% | 43,961 psi | 69% | 2989 fps | 95.1% |
| Hodgdon H4350 | <<locked>> | 90% | 50,589 psi | 79% | 3074 fps | 95.4% |
| Hodgdon H4895 | <<locked>> | 80% | 48,138 psi | 75% | 3022 fps | 99.7% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 30,850 psi | 48% | 2648 fps | 95.5% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 44,541 psi | 70% | 2992 fps | 99.5% |
| Hodgdon Superformance | 51.6 gr | 90% | 46,891 psi | 73% | 3074 fps | 95.4% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,527 psi | 42% | 1755 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 46,209 psi | 72% | 2969 fps | 99.4% |
| IMR 3031 | <<locked>> | 80% | 48,385 psi | 76% | 3018 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 42,554 psi | 67% | 2881 fps | 98.2% |
| IMR 4166 Enduron | <<locked>> | 80% | 45,223 psi | 71% | 2907 fps | 95.4% |
| IMR 4350 | <<locked>> | 92% | 47,065 psi | 74% | 2989 fps | 95.3% |
| IMR 4451 Enduron | <<locked>> | 86% | 45,339 psi | 71% | 2936 fps | 95.3% |
| IMR 4831 | <<locked>> | 84% | 34,635 psi | 54% | 2756 fps | 95.1% |
| IMR 4895 | <<locked>> | 80% | 44,382 psi | 70% | 2969 fps | 99% |
| IMR 8208 XBR | <<locked>> | 80% | 49,705 psi | 78% | 3015 fps | 99.9% |
| Lovex D073.6 | <<locked>> | 80% | 47,398 psi | 74% | 2989 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 47,326 psi | 74% | 2936 fps | 99.3% |
| Lovex S062 | <<locked>> | 80% | 42,641 psi | 67% | 2887 fps | 99.4% |
| Lovex S065 | <<locked>> | 84% | 39,900 psi | 63% | 2822 fps | 95.3% |
| Lovex S070 | <<locked>> | 88% | 43,076 psi | 68% | 2910 fps | 95% |
| Norma 201 | <<locked>> | 80% | 46,630 psi | 73% | 2956 fps | 99.8% |
| Norma 202 | <<locked>> | 80% | 47,282 psi | 74% | 2966 fps | 100% |
| Norma 203B | <<locked>> | 80% | 42,670 psi | 67% | 2923 fps | 98.6% |
| Norma MRP | <<locked>> | 98% | 44,962 psi | 70% | 3084 fps | 95.2% |
| Norma URP | <<locked>> | 84% | 35,926 psi | 56% | 2802 fps | 95.4% |
| Ramshot Big Game | <<locked>> | 80% | 42,525 psi | 67% | 2936 fps | 98.5% |
| Ramshot Hunter | <<locked>> | 90% | 42,830 psi | 67% | 2972 fps | 95.8% |
| Ramshot TAC | <<locked>> | 80% | 49,937 psi | 78% | 3025 fps | 98% |
| Ramshot Wild Boar | <<locked>> | 80% | 49,719 psi | 78% | 3048 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 80% | 53,679 psi | 84% | 3071 fps | 99.8% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 26,992 psi | 42% | 1801 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 44,266 psi | 69% | 2920 fps | 95.8% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 46,195 psi | 72% | 3058 fps | 98.8% |
| ReloadSwiss RS 60 | 43.4 gr | 80% | 37,478 psi | 59% | 2907 fps | 99.7% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 35,694 psi | 56% | 2822 fps | 95% |
| ReloadSwiss RS 70 | 47.3 gr | 86% | 37,840 psi | 59% | 2887 fps | 95% |
| Rottweil R 901 | <<locked>> | 80% | 50,850 psi | 80% | 3005 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 44,628 psi | 70% | 2907 fps | 99.6% |
| Rottweil R 903 | <<locked>> | 80% | 38,000 psi | 60% | 2812 fps | 98.2% |
| Rottweil R 907 | <<locked>> | 88% | 46,499 psi | 73% | 2956 fps | 95.1% |
| Shooters World Long Rifle | <<locked>> | 84% | 39,900 psi | 63% | 2822 fps | 95.3% |
| Shooters World Match Rifle | <<locked>> | 80% | 47,398 psi | 74% | 2989 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 42,641 psi | 67% | 2887 fps | 99.4% |
| Shooters World SW4350 | <<locked>> | 88% | 43,076 psi | 68% | 2910 fps | 95% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 39,015 psi | 61% | 2864 fps | 97.7% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 48,515 psi | 76% | 3002 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 46,311 psi | 73% | 2976 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 47,906 psi | 75% | 2904 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 40,074 psi | 63% | 2756 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 44,744 psi | 70% | 2877 fps | 95.3% |
| Somchem S335 | <<locked>> | 80% | 47,500 psi | 74% | 2904 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 48,138 psi | 75% | 2995 fps | 99.4% |
| Somchem S355 | <<locked>> | 80% | 38,537 psi | 60% | 2815 fps | 98.1% |
| Somchem S365 | <<locked>> | 80% | 28,224 psi | 44% | 2625 fps | 95.7% |
| Somchem S385 | <<locked>> | 98% | 48,066 psi | 75% | 3038 fps | 95.5% |
| Vihtavuori N130 | <<locked>> | 80% | 53,853 psi | 84% | 2969 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 48,283 psi | 76% | 2897 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 44,237 psi | 69% | 2884 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 44,730 psi | 70% | 2890 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 36,825 psi | 58% | 2746 fps | 98.8% |
| Vihtavuori N160 | <<locked>> | 82% | 35,186 psi | 55% | 2753 fps | 95% |
| Vihtavuori N530 | <<locked>> | 80% | 50,125 psi | 79% | 3015 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 43,062 psi | 67% | 2877 fps | 100% |
| Vihtavuori N550 | <<locked>> | 84% | 37,188 psi | 58% | 2812 fps | 95.6% |
| Vihtavuori N555 | <<locked>> | 90% | 33,881 psi | 53% | 2795 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 32,648 psi | 51% | 2661 fps | 96.5% |
| Winchester 748 | <<locked>> | 80% | 50,285 psi | 79% | 3068 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 43,961 psi | 69% | 2989 fps | 95.1% |
| Winchester StaBALL HD | <<locked>> | 94% | 31,560 psi | 49% | 2805 fps | 96.3% |
| Winchester StaBALL Match | <<locked>> | 80% | 46,006 psi | 72% | 2982 fps | 99.5% |
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 95 powders for .255 GS loaded with the .257 | 100gr | Nosler Ballistic Tip Hunting. ReloadSwiss RS 70 delivers the highest muzzle velocity at 3,304 fps; across all powders the maximum-charge window runs from 1,965 fps to 3,304 fps. Accurate 3100 gives the best case fill at 100 %, and 95 of the 95 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 56–90 %, leaving at least 10 % headroom. The 100.0 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. ReloadSwiss RS 70, Hodgdon Superformance, ReloadSwiss RS 60 rank at the top here: for .255 GS with the .257 | 100gr | Nosler Ballistic Tip Hunting 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.