Load Specifications
Bullet Manufacturer:Peregrine
Bullet Weight:87 gr
Bullet Diameter:0.257"
Bullet Length:<<locked>>
Caliber:.257 Roberts load data
Case Length (l3):2.233"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:58 Grains of Water
Primer Size:Large Rifle (LR)
Barrel Length:24"
Max. allowed Pressure:51,488 psi
Recommended Twist Rate:1:9.0
Load data in caliber .257 Roberts with .257 | 87gr | Peregrine Plainsmaster (VLR-4) bullet and 124 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 Reloder-17 and Ramshot Big Game.
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>> | 82% | 45,034 psi | 87% | 3022 fps | 100% |
| Accurate 2015 | <<locked>> | 82% | 44,266 psi | 86% | 3005 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 45,266 psi | 88% | 3074 fps | 100% |
| Accurate 2495 | <<locked>> | 88% | 44,512 psi | 86% | 3058 fps | 100% |
| Accurate 2520 | <<locked>> | 82% | 44,440 psi | 86% | 3077 fps | 99.5% |
| Accurate 2520 | <<locked>> | 82% | 43,772 psi | 85% | 3061 fps | 99.3% |
| Accurate 4064 | <<locked>> | 90% | 45,701 psi | 89% | 3117 fps | 99.9% |
| Accurate 4064 | <<locked>> | 90% | 44,672 psi | 87% | 3091 fps | 99.9% |
| Accurate 4350 | <<locked>> | 98% | 44,846 psi | 87% | 3153 fps | 96% |
| ADI AR 2206H | <<locked>> | 84% | 44,570 psi | 87% | 3087 fps | 97.3% |
| ADI AR 2206H | <<locked>> | 86% | 46,514 psi | 90% | 3123 fps | 97.6% |
| ADI AR 2208 | <<locked>> | 90% | 45,542 psi | 88% | 3084 fps | 96.8% |
| ADI AR 2208 | <<locked>> | 90% | 44,976 psi | 87% | 3064 fps | 96.5% |
| ADI Benchmark 8208 | <<locked>> | 82% | 43,816 psi | 85% | 3041 fps | 98.2% |
| ADI Benchmark 8208 | <<locked>> | 84% | 46,006 psi | 89% | 3084 fps | 98.5% |
| Alliant AR-Comp | <<locked>> | 84% | 46,369 psi | 90% | 3110 fps | 100% |
| Alliant AR-Comp | <<locked>> | 84% | 45,194 psi | 88% | 3087 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 46,499 psi | 90% | 3235 fps | 96.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 88% | 45,643 psi | 89% | 3209 fps | 96.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 44,875 psi | 87% | 3107 fps | 98.2% |
| Alliant Reloder- TS 15.5 | <<locked>> | 90% | 43,961 psi | 85% | 3084 fps | 97.9% |
| Alliant Reloder-15 | <<locked>> | 88% | 45,310 psi | 88% | 3120 fps | 96.9% |
| Alliant Reloder-15 | <<locked>> | 88% | 44,701 psi | 87% | 3104 fps | 96.7% |
| Alliant Reloder-16 | <<locked>> | 98% | 44,773 psi | 87% | 3163 fps | 96.1% |
| Alliant Reloder-17 | <<locked>> | 94% | 44,933 psi | 87% | 3199 fps | 97.9% |
| Alliant Reloder-17 | <<locked>> | 94% | 44,237 psi | 86% | 3179 fps | 97.6% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 43,947 psi | 85% | 3084 fps | 95.9% |
| Baschieri & Pellagri 107 | <<locked>> | 86% | 46,195 psi | 90% | 3123 fps | 96.4% |
| Bofors RP3 | <<locked>> | 90% | 44,425 psi | 86% | 3107 fps | 98.2% |
| Bofors RP3 | <<locked>> | 90% | 43,830 psi | 85% | 3091 fps | 98% |
| Hodgdon Benchmark | <<locked>> | 82% | 45,832 psi | 89% | 3045 fps | 99% |
| Hodgdon Benchmark | <<locked>> | 82% | 45,165 psi | 88% | 3025 fps | 98.8% |
| Hodgdon BL-C2 | <<locked>> | 84% | 45,208 psi | 88% | 3117 fps | 99% |
| Hodgdon BL-C2 | <<locked>> | 84% | 44,628 psi | 87% | 3100 fps | 98.8% |
| Hodgdon CFE223 | <<locked>> | 82% | 45,672 psi | 89% | 3186 fps | 96.9% |
| Hodgdon H4895 | <<locked>> | 84% | 44,976 psi | 87% | 3100 fps | 97.9% |
| Hodgdon H4895 | <<locked>> | 84% | 44,019 psi | 85% | 3077 fps | 97.6% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 43,700 psi | 85% | 3094 fps | 97.6% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 42,627 psi | 83% | 3068 fps | 97.1% |
| Hodgdon LEVERevolution | <<locked>> | 86% | 43,439 psi | 84% | 3117 fps | 98% |
| Hodgdon LEVERevolution | <<locked>> | 88% | 45,687 psi | 89% | 3163 fps | 98.4% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,461 psi | 67% | 2034 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,548 psi | 67% | 2028 fps | 100% |
| Hodgdon VARGET | <<locked>> | 86% | 46,296 psi | 90% | 3110 fps | 98.1% |
| Hodgdon VARGET | <<locked>> | 86% | 45,339 psi | 88% | 3087 fps | 97.8% |
| IMR 3031 | <<locked>> | 84% | 43,845 psi | 85% | 3107 fps | 100% |
| IMR 3031 | <<locked>> | 86% | 46,122 psi | 90% | 3146 fps | 100% |
| IMR 4064 | <<locked>> | 88% | 44,962 psi | 87% | 3068 fps | 96.9% |
| IMR 4064 | <<locked>> | 88% | 44,338 psi | 86% | 3048 fps | 96.6% |
| IMR 4831ᴾ | <<locked>> | 100% | 45,905 psi | 89% | 3153 fps | 96.4% |
| IMR 4831ᴾ | <<locked>> | 100% | 44,759 psi | 87% | 3123 fps | 96% |
| IMR 4895 | <<locked>> | 88% | 46,427 psi | 90% | 3159 fps | 97.8% |
| IMR 4895 | <<locked>> | 88% | 45,803 psi | 89% | 3140 fps | 97.5% |
| IMR 8208 XBR | <<locked>> | 82% | 43,816 psi | 85% | 3041 fps | 98.2% |
| IMR 8208 XBR | <<locked>> | 84% | 46,006 psi | 89% | 3084 fps | 98.5% |
| Lovex D073.6 | <<locked>> | 86% | 46,050 psi | 89% | 3120 fps | 99.6% |
| Lovex D073.6 | <<locked>> | 86% | 45,411 psi | 88% | 3104 fps | 99.5% |
| Lovex S060 | <<locked>> | 84% | 45,005 psi | 87% | 3025 fps | 97.4% |
| Lovex S060 | <<locked>> | 84% | 44,396 psi | 86% | 3005 fps | 97.2% |
| Lovex S062 | <<locked>> | 88% | 44,469 psi | 86% | 3068 fps | 98.5% |
| Lovex S062 | <<locked>> | 88% | 43,830 psi | 85% | 3051 fps | 98.3% |
| Norma 201 | <<locked>> | 86% | 46,137 psi | 90% | 3091 fps | 98.7% |
| Norma 201 | <<locked>> | 86% | 45,484 psi | 88% | 3071 fps | 98.5% |
| Norma 202 | <<locked>> | 86% | 46,499 psi | 90% | 3107 fps | 99.9% |
| Norma 202 | <<locked>> | 86% | 45,832 psi | 89% | 3091 fps | 99.8% |
| Norma 203B | <<locked>> | 88% | 44,527 psi | 86% | 3107 fps | 97.3% |
| Norma 203B | <<locked>> | 88% | 43,918 psi | 85% | 3087 fps | 97.1% |
| Norma URP | <<locked>> | 98% | 44,991 psi | 87% | 3150 fps | 96% |
| Ramshot Big Game | <<locked>> | 88% | 44,527 psi | 86% | 3120 fps | 97.1% |
| Ramshot Big Game | <<locked>> | 88% | 43,714 psi | 85% | 3100 fps | 96.8% |
| Ramshot Wild Boar | <<locked>> | 84% | 46,340 psi | 90% | 3123 fps | 97.6% |
| Ramshot Wild Boar | <<locked>> | 84% | 45,440 psi | 88% | 3104 fps | 97.3% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,708 psi | 67% | 2080 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 34,780 psi | 68% | 2073 fps | 100% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 44,614 psi | 87% | 3176 fps | 96.7% |
| ReloadSwiss RS 52 | <<locked>> | 86% | 43,627 psi | 85% | 3150 fps | 96.3% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 45,092 psi | 88% | 3222 fps | 99.7% |
| ReloadSwiss RS 60 | <<locked>> | 92% | 44,019 psi | 85% | 3192 fps | 99.5% |
| Rottweil R 901 | <<locked>> | 82% | 44,324 psi | 86% | 3038 fps | 99.6% |
| Rottweil R 901 | <<locked>> | 84% | 46,485 psi | 90% | 3077 fps | 99.8% |
| Rottweil R 902 | <<locked>> | 88% | 46,485 psi | 90% | 3087 fps | 98.8% |
| Rottweil R 902 | <<locked>> | 88% | 45,847 psi | 89% | 3071 fps | 98.6% |
| Rottweil R 903 | <<locked>> | 92% | 44,672 psi | 87% | 3104 fps | 98% |
| Rottweil R 903 | <<locked>> | 92% | 43,729 psi | 85% | 3081 fps | 97.7% |
| Shooters World Match Rifle | <<locked>> | 86% | 46,050 psi | 89% | 3120 fps | 99.6% |
| Shooters World Match Rifle | <<locked>> | 86% | 45,411 psi | 88% | 3104 fps | 99.5% |
| Shooters World Precision | <<locked>> | 88% | 44,469 psi | 86% | 3068 fps | 98.5% |
| Shooters World Precision | <<locked>> | 88% | 43,830 psi | 85% | 3051 fps | 98.3% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 46,267 psi | 90% | 3163 fps | 97.6% |
| SNPE Vectan SP 11 | <<locked>> | 92% | 45,455 psi | 88% | 3143 fps | 97.3% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 45,963 psi | 89% | 3107 fps | 97.6% |
| SNPE Vectan SP 9 | <<locked>> | 86% | 45,049 psi | 87% | 3084 fps | 97.3% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 45,208 psi | 88% | 3002 fps | 99.8% |
| SNPE Vectan Tubal 3000 | <<locked>> | 84% | 44,527 psi | 86% | 2982 fps | 99.7% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 45,179 psi | 88% | 3002 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 90% | 44,266 psi | 86% | 2979 fps | 100% |
| Somchem S335 | <<locked>> | 84% | 44,599 psi | 87% | 2999 fps | 100% |
| Somchem S335 | <<locked>> | 84% | 43,947 psi | 85% | 2982 fps | 99.9% |
| Somchem S341 | <<locked>> | 84% | 44,788 psi | 87% | 3068 fps | 97.2% |
| Somchem S341 | <<locked>> | 84% | 43,947 psi | 85% | 3045 fps | 96.9% |
| Somchem S355 | <<locked>> | 92% | 45,484 psi | 88% | 3107 fps | 98% |
| Somchem S355 | <<locked>> | 92% | 44,585 psi | 87% | 3084 fps | 97.7% |
| Somchem S365ᴾ | <<locked>> | 100% | 42,496 psi | 83% | 3143 fps | 98.6% |
| Somchem S365ᴾ | <<locked>> | 100% | 41,771 psi | 81% | 3123 fps | 98.4% |
| Vihtavuori N133 | <<locked>> | 84% | 45,353 psi | 88% | 3002 fps | 100% |
| Vihtavuori N133 | <<locked>> | 84% | 44,657 psi | 87% | 2982 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 45,861 psi | 89% | 3081 fps | 100% |
| Vihtavuori N135 | <<locked>> | 88% | 45,136 psi | 88% | 3064 fps | 100% |
| Vihtavuori N140 | <<locked>> | 86% | 44,295 psi | 86% | 3038 fps | 99.9% |
| Vihtavuori N140 | <<locked>> | 88% | 46,195 psi | 90% | 3068 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 92% | 43,772 psi | 85% | 3038 fps | 98.7% |
| Vihtavuori N150 | <<locked>> | 94% | 45,861 psi | 89% | 3074 fps | 99% |
| Vihtavuori N160 | <<locked>> | 98% | 46,311 psi | 90% | 3130 fps | 96.1% |
| Vihtavuori N530 | <<locked>> | 82% | 43,787 psi | 85% | 3035 fps | 98.3% |
| Vihtavuori N530 | <<locked>> | 84% | 46,050 psi | 89% | 3077 fps | 98.6% |
| Vihtavuori N540 | <<locked>> | 88% | 45,382 psi | 88% | 3071 fps | 99.8% |
| Vihtavuori N540 | <<locked>> | 88% | 44,860 psi | 87% | 3058 fps | 99.7% |
| Vihtavuori N550 | <<locked>> | 98% | 46,557 psi | 90% | 3156 fps | 96.1% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 45,353 psi | 88% | 3081 fps | 98.1% |
| Winchester 6.5 StaBALL | <<locked>> | 96% | 44,512 psi | 86% | 3054 fps | 97.8% |
| Winchester 748 | <<locked>> | 84% | 46,238 psi | 90% | 3146 fps | 99.3% |
| Winchester 748 | <<locked>> | 84% | 45,237 psi | 88% | 3123 fps | 99.1% |
| Winchester StaBALL Match | <<locked>> | 86% | 45,455 psi | 88% | 3110 fps | 98% |
| Winchester StaBALL Match | <<locked>> | 86% | 44,556 psi | 87% | 3091 fps | 97.8% |
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% | 42,192 psi | 82% | 2966 fps | 100% |
| Accurate 2015 | <<locked>> | 80% | 41,423 psi | 80% | 2946 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 34,287 psi | 67% | 2838 fps | 99.8% |
| Accurate 2495 | <<locked>> | 80% | 33,808 psi | 66% | 2825 fps | 99.7% |
| Accurate 2520 | <<locked>> | 80% | 41,379 psi | 80% | 3015 fps | 99.1% |
| Accurate 2520 | <<locked>> | 80% | 40,683 psi | 79% | 2995 fps | 98.9% |
| Accurate 4064 | <<locked>> | 80% | 32,430 psi | 63% | 2812 fps | 97.9% |
| Accurate 4064 | <<locked>> | 80% | 31,995 psi | 62% | 2795 fps | 97.6% |
| Accurate 4350 | <<locked>> | 96% | 41,510 psi | 81% | 3077 fps | 95% |
| ADI AR 2206H | <<locked>> | 80% | 39,059 psi | 76% | 2959 fps | 95.7% |
| ADI AR 2206H | <<locked>> | 80% | 38,421 psi | 75% | 2940 fps | 95.3% |
| ADI AR 2208 | <<locked>> | 86% | 40,161 psi | 78% | 2963 fps | 95.2% |
| ADI AR 2208 | <<locked>> | 88% | 42,221 psi | 82% | 3005 fps | 95.8% |
| ADI Benchmark 8208 | <<locked>> | 80% | 41,162 psi | 80% | 2986 fps | 97.6% |
| ADI Benchmark 8208 | <<locked>> | 80% | 40,495 psi | 79% | 2966 fps | 97.4% |
| Alliant AR-Comp | <<locked>> | 80% | 40,089 psi | 78% | 2992 fps | 100% |
| Alliant AR-Comp | <<locked>> | 80% | 39,247 psi | 76% | 2972 fps | 100% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 43,352 psi | 84% | 3163 fps | 95.8% |
| Alliant Power Pro 2000-MR | <<locked>> | 86% | 42,554 psi | 83% | 3136 fps | 95.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 34,476 psi | 67% | 2861 fps | 95.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 84% | 36,172 psi | 70% | 2900 fps | 95.7% |
| Alliant Reloder-15 | <<locked>> | 84% | 39,943 psi | 78% | 2999 fps | 95.4% |
| Alliant Reloder-15 | <<locked>> | 86% | 41,611 psi | 81% | 3035 fps | 95.8% |
| Alliant Reloder-16 | <<locked>> | 96% | 41,800 psi | 81% | 3094 fps | 95.1% |
| Alliant Reloder-17 | 42.9 gr | 88% | 36,709 psi | 71% | 2995 fps | 95.1% |
| Alliant Reloder-17 | 43.8 gr | 90% | 38,377 psi | 75% | 3035 fps | 95.7% |
| Baschieri & Pellagri 107 | <<locked>> | 82% | 40,988 psi | 80% | 3018 fps | 95% |
| Baschieri & Pellagri 107 | <<locked>> | 84% | 43,076 psi | 84% | 3058 fps | 95.5% |
| Bofors RP3 | <<locked>> | 82% | 33,620 psi | 65% | 2851 fps | 95% |
| Bofors RP3 | <<locked>> | 84% | 35,302 psi | 69% | 2890 fps | 95.5% |
| Hodgdon Benchmark | <<locked>> | 80% | 43,076 psi | 84% | 2986 fps | 98.6% |
| Hodgdon Benchmark | <<locked>> | 80% | 42,438 psi | 82% | 2966 fps | 98.3% |
| Hodgdon BL-C2 | <<locked>> | 80% | 39,276 psi | 76% | 2989 fps | 97.8% |
| Hodgdon BL-C2 | <<locked>> | 80% | 38,653 psi | 75% | 2966 fps | 97.5% |
| Hodgdon CFE223 | <<locked>> | 80% | 42,496 psi | 83% | 3114 fps | 96% |
| Hodgdon H4895 | <<locked>> | 80% | 39,334 psi | 76% | 2972 fps | 96.4% |
| Hodgdon H4895 | <<locked>> | 80% | 38,682 psi | 75% | 2953 fps | 96.1% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 38,101 psi | 74% | 2966 fps | 95.9% |
| Hodgdon Hybrid 100V | <<locked>> | 96% | 37,376 psi | 73% | 2943 fps | 95.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 35,114 psi | 68% | 2913 fps | 95.4% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 34,534 psi | 67% | 2894 fps | 95.1% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,425 psi | 49% | 1818 fps | 100% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,367 psi | 49% | 1811 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 37,739 psi | 73% | 2917 fps | 95.8% |
| Hodgdon VARGET | <<locked>> | 80% | 37,130 psi | 72% | 2897 fps | 95.5% |
| IMR 3031 | <<locked>> | 80% | 38,247 psi | 74% | 2986 fps | 99.8% |
| IMR 3031 | <<locked>> | 80% | 37,492 psi | 73% | 2966 fps | 99.7% |
| IMR 4064 | <<locked>> | 84% | 39,581 psi | 77% | 2946 fps | 95.3% |
| IMR 4064 | <<locked>> | 84% | 38,972 psi | 76% | 2927 fps | 95% |
| IMR 4831 | <<locked>> | 98% | 43,033 psi | 84% | 3091 fps | 95.6% |
| IMR 4831 | <<locked>> | 98% | 41,887 psi | 81% | 3061 fps | 95.1% |
| IMR 4895 | <<locked>> | 82% | 38,072 psi | 74% | 2969 fps | 95.5% |
| IMR 4895 | <<locked>> | 82% | 37,463 psi | 73% | 2949 fps | 95.1% |
| IMR 8208 XBR | <<locked>> | 80% | 41,162 psi | 80% | 2986 fps | 97.6% |
| IMR 8208 XBR | <<locked>> | 80% | 40,495 psi | 79% | 2966 fps | 97.4% |
| Lovex D073.6 | <<locked>> | 80% | 37,304 psi | 72% | 2930 fps | 98.2% |
| Lovex D073.6 | <<locked>> | 80% | 36,622 psi | 71% | 2910 fps | 98% |
| Lovex S060 | <<locked>> | 80% | 39,523 psi | 77% | 2904 fps | 95.9% |
| Lovex S060 | <<locked>> | 80% | 38,899 psi | 76% | 2881 fps | 95.6% |
| Lovex S062 | <<locked>> | 80% | 34,214 psi | 66% | 2825 fps | 95.6% |
| Lovex S062 | <<locked>> | 80% | 33,562 psi | 65% | 2802 fps | 95.2% |
| Norma 201 | <<locked>> | 80% | 37,884 psi | 74% | 2907 fps | 96.8% |
| Norma 201 | <<locked>> | 80% | 37,492 psi | 73% | 2894 fps | 96.6% |
| Norma 202 | <<locked>> | 80% | 38,087 psi | 74% | 2927 fps | 98.9% |
| Norma 202 | <<locked>> | 80% | 37,695 psi | 73% | 2913 fps | 98.8% |
| Norma 203B | <<locked>> | 84% | 39,218 psi | 76% | 2986 fps | 95.8% |
| Norma 203B | <<locked>> | 84% | 38,363 psi | 75% | 2959 fps | 95.4% |
| Norma URP | <<locked>> | 96% | 41,872 psi | 81% | 3081 fps | 95% |
| Ramshot Big Game | 41.6 gr | 84% | 38,754 psi | 75% | 2989 fps | 95.4% |
| Ramshot Big Game | 41.6 gr | 84% | 38,261 psi | 74% | 2972 fps | 95% |
| Ramshot Wild Boar | <<locked>> | 80% | 40,089 psi | 78% | 2989 fps | 96% |
| Ramshot Wild Boar | <<locked>> | 80% | 39,494 psi | 77% | 2969 fps | 95.7% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,744 psi | 50% | 1864 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,672 psi | 50% | 1857 fps | 100% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 41,452 psi | 81% | 3107 fps | 95.8% |
| ReloadSwiss RS 52 | <<locked>> | 84% | 40,770 psi | 79% | 3084 fps | 95.4% |
| ReloadSwiss RS 60 | 39.9 gr | 82% | 31,850 psi | 62% | 2864 fps | 95.6% |
| ReloadSwiss RS 60 | 39.9 gr | 82% | 31,183 psi | 61% | 2835 fps | 95% |
| Rottweil R 901 | <<locked>> | 80% | 41,655 psi | 81% | 2979 fps | 99.3% |
| Rottweil R 901 | <<locked>> | 80% | 40,901 psi | 79% | 2959 fps | 99.1% |
| Rottweil R 902 | <<locked>> | 80% | 36,027 psi | 70% | 2851 fps | 96.2% |
| Rottweil R 902 | <<locked>> | 80% | 35,404 psi | 69% | 2831 fps | 95.9% |
| Rottweil R 903 | <<locked>> | 86% | 36,376 psi | 71% | 2913 fps | 95.7% |
| Rottweil R 903 | <<locked>> | 86% | 35,476 psi | 69% | 2887 fps | 95.2% |
| Shooters World Match Rifle | <<locked>> | 80% | 37,304 psi | 72% | 2930 fps | 98.2% |
| Shooters World Match Rifle | <<locked>> | 80% | 36,622 psi | 71% | 2910 fps | 98% |
| Shooters World Precision | <<locked>> | 80% | 34,214 psi | 66% | 2825 fps | 95.6% |
| Shooters World Precision | <<locked>> | 80% | 33,562 psi | 65% | 2802 fps | 95.2% |
| SNPE Vectan SP 11 | <<locked>> | 86% | 37,797 psi | 73% | 2972 fps | 95.1% |
| SNPE Vectan SP 11 | <<locked>> | 88% | 39,755 psi | 77% | 3015 fps | 95.7% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 37,608 psi | 73% | 2917 fps | 95.2% |
| SNPE Vectan SP 9 | <<locked>> | 82% | 39,436 psi | 77% | 2956 fps | 95.7% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 39,668 psi | 77% | 2887 fps | 99.2% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 39,001 psi | 76% | 2867 fps | 99% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 32,590 psi | 63% | 2723 fps | 98.5% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 31,966 psi | 62% | 2703 fps | 98.2% |
| Somchem S335 | <<locked>> | 80% | 39,117 psi | 76% | 2884 fps | 99.5% |
| Somchem S335 | <<locked>> | 80% | 38,740 psi | 75% | 2874 fps | 99.4% |
| Somchem S341 | <<locked>> | 80% | 38,653 psi | 75% | 2930 fps | 95.4% |
| Somchem S341 | <<locked>> | 80% | 38,130 psi | 74% | 2913 fps | 95.1% |
| Somchem S355 | <<locked>> | 86% | 37,318 psi | 72% | 2923 fps | 95.7% |
| Somchem S355 | <<locked>> | 86% | 36,738 psi | 71% | 2904 fps | 95.4% |
| Somchem S365 | <<locked>> | 92% | 32,634 psi | 63% | 2884 fps | 95.2% |
| Somchem S365 | <<locked>> | 94% | 34,069 psi | 66% | 2923 fps | 95.8% |
| Vihtavuori N133 | <<locked>> | 80% | 39,885 psi | 77% | 2894 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 39,189 psi | 76% | 2874 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 35,070 psi | 68% | 2854 fps | 99.8% |
| Vihtavuori N135 | <<locked>> | 80% | 34,330 psi | 67% | 2835 fps | 99.7% |
| Vihtavuori N140 | <<locked>> | 80% | 36,260 psi | 70% | 2861 fps | 98.8% |
| Vihtavuori N140 | <<locked>> | 80% | 35,621 psi | 69% | 2841 fps | 98.6% |
| Vihtavuori N150 | <<locked>> | 82% | 31,140 psi | 60% | 2733 fps | 95% |
| Vihtavuori N150 | <<locked>> | 84% | 32,677 psi | 63% | 2772 fps | 95.5% |
| Vihtavuori N160 | <<locked>> | 96% | 43,366 psi | 84% | 3068 fps | 95.2% |
| Vihtavuori N530 | <<locked>> | 80% | 41,060 psi | 80% | 2979 fps | 97.7% |
| Vihtavuori N530 | <<locked>> | 80% | 40,393 psi | 78% | 2956 fps | 97.4% |
| Vihtavuori N540 | <<locked>> | 80% | 34,824 psi | 68% | 2835 fps | 98% |
| Vihtavuori N540 | <<locked>> | 80% | 34,243 psi | 67% | 2815 fps | 97.8% |
| Vihtavuori N550 | <<locked>> | 96% | 43,381 psi | 84% | 3091 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 36,825 psi | 72% | 2884 fps | 95.5% |
| Winchester 6.5 StaBALL | <<locked>> | 90% | 36,245 psi | 70% | 2861 fps | 95.1% |
| Winchester 748 | <<locked>> | 80% | 40,059 psi | 78% | 3015 fps | 98.2% |
| Winchester 748 | <<locked>> | 80% | 39,421 psi | 77% | 2995 fps | 98% |
| Winchester StaBALL Match | <<locked>> | 80% | 36,782 psi | 71% | 2917 fps | 95.6% |
| Winchester StaBALL Match | <<locked>> | 80% | 36,201 psi | 70% | 2894 fps | 95.3% |
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 124 powders for .257 Roberts loaded with the .257 | 87gr | Peregrine Plainsmaster (VLR-4). Alliant Power Pro 2000-MR delivers the highest muzzle velocity at 3,235 fps; across all powders the maximum-charge window runs from 2,028 fps to 3,235 fps. Hodgdon Hybrid 100V gives the best case fill at 100 %, and 124 of the 124 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (355 MPa), the top charges use 67–90 %, leaving at least 10 % headroom. The 87.0 gr projectile in 0.257" calls for a 1:9.0 twist; slower twists will usually not stabilise this weight. Hodgdon Hybrid 100V, Hodgdon Hybrid 100V, Hodgdon TrailBoss 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 Reloder-17, Ramshot Big Game rank at the top here: for .257 Roberts with the .257 | 87gr | Peregrine Plainsmaster (VLR-4) 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.