Load Specifications
Load data in caliber .255 GS with .257 | 100gr | Swift A-Frame 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, Alliant Reloder-17 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% | 55,825 psi | 87% | 3041 fps | 100% |
| Accurate 2495 | <<locked>> | 86% | 55,303 psi | 87% | 3064 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 57,000 psi | 89% | 3136 fps | 100% |
| Accurate 2700 | <<locked>> | 88% | 57,609 psi | 90% | 3123 fps | 97.4% |
| Accurate 3100ᴾ | <<locked>> | 100% | 46,485 psi | 73% | 3012 fps | 97% |
| Accurate 4064 | <<locked>> | 88% | 55,695 psi | 87% | 3120 fps | 100% |
| Accurate 4350 | <<locked>> | 96% | 56,014 psi | 88% | 3212 fps | 99.7% |
| ADI AR 2206H | <<locked>> | 84% | 55,390 psi | 87% | 3153 fps | 99.9% |
| ADI AR 2208 | <<locked>> | 90% | 56,275 psi | 88% | 3150 fps | 99.8% |
| ADI Benchmark 8208 | <<locked>> | 84% | 57,667 psi | 90% | 3153 fps | 100% |
| Alliant AR-Comp | <<locked>> | 82% | 55,303 psi | 87% | 3071 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 55,390 psi | 87% | 3281 fps | 99.9% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 56,942 psi | 89% | 3179 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 88% | 57,319 psi | 90% | 3202 fps | 99.9% |
| Alliant Reloder-16 | <<locked>> | 98% | 56,782 psi | 89% | 3274 fps | 99.9% |
| Alliant Reloder-17 | <<locked>> | 92% | 54,665 psi | 86% | 3251 fps | 100% |
| Alliant Reloder-19ᴾ | <<locked>> | 100% | 52,881 psi | 83% | 3166 fps | 95.8% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 43,888 psi | 69% | 3045 fps | 99.4% |
| Alliant Reloder-26ᴾ | <<locked>> | 100% | 49,966 psi | 78% | 3235 fps | 99.1% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 55,100 psi | 86% | 3159 fps | 99.6% |
| Bofors RP3 | <<locked>> | 88% | 54,070 psi | 85% | 3136 fps | 100% |
| Bofors RP7 | <<locked>> | 94% | 57,305 psi | 90% | 3159 fps | 97.6% |
| Hodgdon Benchmark | <<locked>> | 82% | 55,666 psi | 87% | 3077 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 84% | 57,711 psi | 90% | 3182 fps | 100% |
| Hodgdon H380 | <<locked>> | 88% | 54,810 psi | 86% | 3150 fps | 99.3% |
| Hodgdon H414 | <<locked>> | 94% | 54,795 psi | 86% | 3202 fps | 97.8% |
| Hodgdon H4350 | <<locked>> | 92% | 55,056 psi | 86% | 3163 fps | 96.6% |
| Hodgdon H4895 | <<locked>> | 84% | 55,956 psi | 88% | 3163 fps | 100% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 56,985 psi | 89% | 3192 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 55,608 psi | 87% | 3196 fps | 100% |
| Hodgdon Superformance | <<locked>> | 94% | 55,347 psi | 87% | 3238 fps | 97.6% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 35,911 psi | 56% | 1978 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 57,116 psi | 90% | 3166 fps | 100% |
| IMR 3031 | <<locked>> | 84% | 56,173 psi | 88% | 3143 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 55,767 psi | 87% | 3133 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 86% | 55,593 psi | 87% | 3110 fps | 97.8% |
| IMR 4350 | <<locked>> | 96% | 54,375 psi | 85% | 3130 fps | 97.2% |
| IMR 4451 Enduron | <<locked>> | 92% | 55,637 psi | 87% | 3136 fps | 97.8% |
| IMR 4831 | <<locked>> | 98% | 56,391 psi | 88% | 3199 fps | 99.7% |
| IMR 4895 | <<locked>> | 86% | 55,027 psi | 86% | 3173 fps | 100% |
| IMR 8208 XBR | <<locked>> | 84% | 57,667 psi | 90% | 3153 fps | 100% |
| Lovex D073.6 | <<locked>> | 84% | 55,361 psi | 87% | 3123 fps | 100% |
| Lovex S060 | <<locked>> | 84% | 54,549 psi | 85% | 3071 fps | 99.9% |
| Lovex S062 | <<locked>> | 88% | 55,782 psi | 87% | 3130 fps | 100% |
| Lovex S065 | <<locked>> | 94% | 55,448 psi | 87% | 3133 fps | 98.9% |
| Lovex S070 | <<locked>> | 96% | 56,333 psi | 88% | 3169 fps | 98.2% |
| Norma 201 | <<locked>> | 86% | 57,334 psi | 90% | 3143 fps | 100% |
| Norma 202 | <<locked>> | 84% | 54,766 psi | 86% | 3094 fps | 100% |
| Norma 203B | <<locked>> | 88% | 56,521 psi | 89% | 3186 fps | 100% |
| Norma 204 | <<locked>> | 96% | 55,042 psi | 86% | 3179 fps | 96% |
| Norma MRPᴾ | <<locked>> | 100% | 49,240 psi | 77% | 3179 fps | 96.6% |
| Norma URP | <<locked>> | 96% | 54,636 psi | 86% | 3192 fps | 99.5% |
| Ramshot Big Game | <<locked>> | 88% | 57,392 psi | 90% | 3212 fps | 100% |
| Ramshot Hunter | <<locked>> | 98% | 57,261 psi | 90% | 3248 fps | 98.9% |
| Ramshot TAC | <<locked>> | 82% | 54,302 psi | 85% | 3110 fps | 98.8% |
| Ramshot Wild Boar | <<locked>> | 82% | 54,215 psi | 85% | 3133 fps | 99.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 36,347 psi | 57% | 2021 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 88% | 54,766 psi | 86% | 3123 fps | 98.2% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 54,244 psi | 85% | 3212 fps | 99.8% |
| ReloadSwiss RS 60 | <<locked>> | 90% | 54,273 psi | 85% | 3251 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 96% | 55,825 psi | 87% | 3235 fps | 99.5% |
| ReloadSwiss RS 70 | <<locked>> | 96% | 54,926 psi | 86% | 3261 fps | 99.4% |
| Rottweil R 901 | <<locked>> | 82% | 55,013 psi | 86% | 3077 fps | 100% |
| Rottweil R 902 | <<locked>> | 86% | 54,592 psi | 86% | 3091 fps | 100% |
| Rottweil R 903 | <<locked>> | 92% | 57,740 psi | 90% | 3186 fps | 100% |
| Rottweil R 907 | <<locked>> | 94% | 57,305 psi | 90% | 3159 fps | 97.6% |
| Shooters World Long Rifle | <<locked>> | 94% | 55,448 psi | 87% | 3133 fps | 98.9% |
| Shooters World Match Rifle | <<locked>> | 84% | 55,361 psi | 87% | 3123 fps | 100% |
| Shooters World Precision | <<locked>> | 88% | 55,782 psi | 87% | 3130 fps | 100% |
| Shooters World SW4350 | <<locked>> | 96% | 56,333 psi | 88% | 3169 fps | 98.2% |
| SNPE Vectan SP 11 | <<locked>> | 90% | 55,796 psi | 87% | 3192 fps | 100% |
| SNPE Vectan SP 7 | <<locked>> | 84% | 56,652 psi | 89% | 3150 fps | 99.4% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 57,319 psi | 90% | 3173 fps | 100% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 55,245 psi | 87% | 3028 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 55,898 psi | 88% | 3028 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 55,637 psi | 87% | 3081 fps | 97.8% |
| Somchem S335 | <<locked>> | 84% | 54,679 psi | 86% | 3022 fps | 100% |
| Somchem S341 | <<locked>> | 84% | 56,144 psi | 88% | 3136 fps | 100% |
| Somchem S355 | <<locked>> | 92% | 57,551 psi | 90% | 3179 fps | 100% |
| Somchem S365ᴾ | <<locked>> | 100% | 57,058 psi | 89% | 3255 fps | 100% |
| Somchem S385ᴾ | <<locked>> | 100% | 52,707 psi | 83% | 3130 fps | 96.8% |
| Vihtavuori N133 | <<locked>> | 84% | 55,622 psi | 87% | 3012 fps | 100% |
| Vihtavuori N135 | <<locked>> | 86% | 54,679 psi | 86% | 3054 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 55,071 psi | 86% | 3068 fps | 100% |
| Vihtavuori N150 | <<locked>> | 92% | 55,738 psi | 87% | 3104 fps | 100% |
| Vihtavuori N160 | <<locked>> | 96% | 57,261 psi | 90% | 3196 fps | 99.7% |
| Vihtavuori N530 | <<locked>> | 82% | 54,549 psi | 85% | 3094 fps | 100% |
| Vihtavuori N540 | <<locked>> | 88% | 57,000 psi | 89% | 3117 fps | 100% |
| Vihtavuori N550 | <<locked>> | 96% | 56,376 psi | 88% | 3196 fps | 99.5% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 48,834 psi | 77% | 3130 fps | 99.3% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 57,305 psi | 90% | 3163 fps | 100% |
| Winchester 748 | <<locked>> | 82% | 54,723 psi | 86% | 3143 fps | 100% |
| Winchester 760 | <<locked>> | 94% | 55,100 psi | 86% | 3209 fps | 97.9% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 39,378 psi | 62% | 3058 fps | 99.6% |
| Winchester StaBALL Match | <<locked>> | 86% | 57,479 psi | 90% | 3182 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% | 52,504 psi | 82% | 2989 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 45,397 psi | 71% | 2907 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 53,214 psi | 83% | 3081 fps | 100% |
| Accurate 2700 | <<locked>> | 82% | 47,268 psi | 74% | 2940 fps | 95.2% |
| Accurate 3100 | <<locked>> | 96% | 40,408 psi | 63% | 2887 fps | 95.3% |
| Accurate 4064 | <<locked>> | 80% | 42,946 psi | 67% | 2904 fps | 100% |
| Accurate 4350 | <<locked>> | 82% | 34,316 psi | 54% | 2766 fps | 95% |
| ADI AR 2206H | <<locked>> | 80% | 48,762 psi | 76% | 3035 fps | 99.5% |
| ADI AR 2208 | <<locked>> | 80% | 41,278 psi | 65% | 2864 fps | 97.8% |
| ADI Benchmark 8208 | <<locked>> | 80% | 50,865 psi | 80% | 3041 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 51,822 psi | 81% | 3018 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 80% | 44,730 psi | 70% | 3071 fps | 98.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 41,394 psi | 65% | 2894 fps | 99.1% |
| Alliant Reloder-15 | <<locked>> | 80% | 44,382 psi | 70% | 2963 fps | 98.6% |
| Alliant Reloder-16 | <<locked>> | 82% | 34,185 psi | 54% | 2782 fps | 95% |
| Alliant Reloder-17 | 44.2 gr | 80% | 35,868 psi | 56% | 2858 fps | 97.6% |
| Alliant Reloder-19 | <<locked>> | 98% | 49,763 psi | 78% | 3107 fps | 95% |
| Alliant Reloder-23 | <<locked>> | 90% | 31,850 psi | 50% | 2736 fps | 95.9% |
| Alliant Reloder-26 | <<locked>> | 92% | 37,202 psi | 58% | 2940 fps | 95.5% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 48,298 psi | 76% | 3038 fps | 98.9% |
| Bofors RP3 | <<locked>> | 80% | 41,234 psi | 65% | 2897 fps | 99.1% |
| Bofors RP7 | <<locked>> | 88% | 47,442 psi | 74% | 2982 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 80% | 52,127 psi | 82% | 3022 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 80% | 50,212 psi | 79% | 3064 fps | 100% |
| Hodgdon H380 | <<locked>> | 80% | 41,989 psi | 66% | 2900 fps | 97% |
| Hodgdon H414 | <<locked>> | 88% | 44,889 psi | 70% | 3012 fps | 95.5% |
| Hodgdon H4350 | <<locked>> | 88% | 48,501 psi | 76% | 3041 fps | 95% |
| Hodgdon H4895 | <<locked>> | 80% | 49,298 psi | 77% | 3045 fps | 99.8% |
| Hodgdon Hybrid 100V | <<locked>> | 82% | 31,488 psi | 49% | 2671 fps | 95.9% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 45,339 psi | 71% | 3012 fps | 99.7% |
| Hodgdon Superformance | <<locked>> | 90% | 47,906 psi | 75% | 3100 fps | 95.9% |
| Hodgdon TrailBoss | <<locked>> | 80% | 26,658 psi | 42% | 1768 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 47,007 psi | 74% | 2989 fps | 99.6% |
| IMR 3031 | <<locked>> | 80% | 49,110 psi | 77% | 3035 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 43,337 psi | 68% | 2904 fps | 98.5% |
| IMR 4166 Enduron | <<locked>> | 80% | 45,948 psi | 72% | 2930 fps | 95.7% |
| IMR 4350 | <<locked>> | 92% | 47,921 psi | 75% | 3012 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 86% | 46,267 psi | 73% | 2963 fps | 95.7% |
| IMR 4831 | <<locked>> | 84% | 35,578 psi | 56% | 2782 fps | 95.6% |
| IMR 4895 | <<locked>> | 80% | 45,513 psi | 71% | 2999 fps | 99.2% |
| IMR 8208 XBR | <<locked>> | 80% | 50,865 psi | 80% | 3041 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 48,225 psi | 76% | 3009 fps | 100% |
| Lovex S060 | <<locked>> | 80% | 48,124 psi | 75% | 2959 fps | 99.5% |
| Lovex S062 | <<locked>> | 80% | 43,453 psi | 68% | 2907 fps | 99.6% |
| Lovex S065 | <<locked>> | 84% | 40,596 psi | 64% | 2844 fps | 95.7% |
| Lovex S070 | <<locked>> | 88% | 43,961 psi | 69% | 2933 fps | 95.5% |
| Norma 201 | <<locked>> | 80% | 47,485 psi | 74% | 2976 fps | 99.9% |
| Norma 202 | <<locked>> | 80% | 48,153 psi | 75% | 2986 fps | 100% |
| Norma 203B | <<locked>> | 80% | 43,772 psi | 69% | 2949 fps | 98.9% |
| Norma 204 | <<locked>> | 94% | 51,634 psi | 81% | 3120 fps | 95.2% |
| Norma MRP | <<locked>> | 98% | 45,934 psi | 72% | 3110 fps | 95.7% |
| Norma URP | <<locked>> | 84% | 36,898 psi | 58% | 2831 fps | 95.9% |
| Ramshot Big Game | <<locked>> | 80% | 43,526 psi | 68% | 2963 fps | 98.8% |
| Ramshot Hunter | <<locked>> | 88% | 41,060 psi | 64% | 2936 fps | 95.3% |
| Ramshot TAC | <<locked>> | 80% | 50,908 psi | 80% | 3051 fps | 98.3% |
| Ramshot Wild Boar | <<locked>> | 80% | 50,778 psi | 80% | 3071 fps | 99.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,122 psi | 43% | 1811 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 42,308 psi | 66% | 2884 fps | 95.4% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 47,137 psi | 74% | 3081 fps | 99% |
| ReloadSwiss RS 60 | 44.2 gr | 80% | 38,174 psi | 60% | 2930 fps | 99.8% |
| ReloadSwiss RS 62 | <<locked>> | 84% | 36,622 psi | 57% | 2848 fps | 95.5% |
| ReloadSwiss RS 70 | 48.3 gr | 86% | 38,841 psi | 61% | 2920 fps | 95.6% |
| Rottweil R 901 | <<locked>> | 80% | 51,808 psi | 81% | 3025 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 45,469 psi | 71% | 2930 fps | 99.7% |
| Rottweil R 903 | <<locked>> | 80% | 38,812 psi | 61% | 2835 fps | 98.5% |
| Rottweil R 907 | <<locked>> | 88% | 47,442 psi | 74% | 2982 fps | 95.5% |
| Shooters World Long Rifle | <<locked>> | 84% | 40,596 psi | 64% | 2844 fps | 95.7% |
| Shooters World Match Rifle | <<locked>> | 80% | 48,225 psi | 76% | 3009 fps | 100% |
| Shooters World Precision | <<locked>> | 80% | 43,453 psi | 68% | 2907 fps | 99.6% |
| Shooters World SW4350 | <<locked>> | 88% | 43,961 psi | 69% | 2933 fps | 95.5% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 39,755 psi | 62% | 2884 fps | 98% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 49,284 psi | 77% | 3022 fps | 98.5% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 47,079 psi | 74% | 2995 fps | 99.3% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 48,776 psi | 76% | 2923 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 40,886 psi | 64% | 2776 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 45,629 psi | 72% | 2900 fps | 95.7% |
| Somchem S335 | <<locked>> | 80% | 48,269 psi | 76% | 2920 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 49,182 psi | 77% | 3018 fps | 99.5% |
| Somchem S355 | <<locked>> | 80% | 39,334 psi | 62% | 2838 fps | 98.4% |
| Somchem S365 | <<locked>> | 80% | 28,892 psi | 45% | 2651 fps | 96.3% |
| Somchem S385 | <<locked>> | 96% | 45,934 psi | 72% | 3002 fps | 95.1% |
| Vihtavuori N133 | <<locked>> | 80% | 49,197 psi | 77% | 2913 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 45,223 psi | 71% | 2907 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 45,556 psi | 71% | 2910 fps | 100% |
| Vihtavuori N150 | <<locked>> | 80% | 37,608 psi | 59% | 2769 fps | 99% |
| Vihtavuori N160 | <<locked>> | 82% | 35,897 psi | 56% | 2772 fps | 95.5% |
| Vihtavuori N530 | <<locked>> | 80% | 50,952 psi | 80% | 3035 fps | 100% |
| Vihtavuori N540 | <<locked>> | 80% | 44,063 psi | 69% | 2900 fps | 100% |
| Vihtavuori N550 | <<locked>> | 82% | 35,563 psi | 56% | 2772 fps | 95% |
| Vihtavuori N555 | <<locked>> | 88% | 32,648 psi | 51% | 2762 fps | 95% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 33,359 psi | 52% | 2687 fps | 96.9% |
| Winchester 748 | <<locked>> | 80% | 51,082 psi | 80% | 3084 fps | 100% |
| Winchester 760 | <<locked>> | 88% | 44,889 psi | 70% | 3012 fps | 95.5% |
| Winchester StaBALL HD | <<locked>> | 92% | 30,284 psi | 47% | 2766 fps | 95.6% |
| Winchester StaBALL Match | <<locked>> | 80% | 47,079 psi | 74% | 3005 fps | 99.6% |
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 | Swift A-Frame. Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,281 fps; across all powders the maximum-charge window runs from 1,978 fps to 3,281 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 1:11.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Alliant Reloder-19, 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 70, Alliant Reloder-17, ReloadSwiss RS 60 rank at the top here: for .255 GS with the .257 | 100gr | Swift A-Frame 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.