Load Specifications
Load data in caliber .257 Weath. Mag. with .257 | 87gr | Remington HP Power-Lokt bullet and 80 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Vihtavuori N560, Norma MRP and ADI AR 2213.
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: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 84% | 55,985 psi | 88% | 3448 fps | 98.7% |
| Accurate 3100 | <<locked>> | 96% | 54,766 psi | 86% | 3494 fps | 99.6% |
| Accurate 4350 | <<locked>> | 88% | 55,898 psi | 88% | 3553 fps | 100% |
| ADI AR 2208 | <<locked>> | 84% | 57,101 psi | 89% | 3527 fps | 100% |
| ADI AR 2209 | <<locked>> | 94% | 57,058 psi | 89% | 3606 fps | 98.3% |
| ADI AR 2213 | <<locked>> | 96% | 54,969 psi | 86% | 3596 fps | 96.9% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 40,872 psi | 64% | 3314 fps | 96.5% |
| Alliant Power Pro Varmint | <<locked>> | 94% | 57,348 psi | 90% | 3602 fps | 98.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 54,868 psi | 86% | 3494 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 56,681 psi | 89% | 3625 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 54,186 psi | 85% | 3576 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 56,608 psi | 89% | 3589 fps | 98.3% |
| Alliant Reloder-22 | <<locked>> | 96% | 54,708 psi | 86% | 3593 fps | 98.1% |
| Alliant Reloder-23 | <<locked>> | 98% | 55,477 psi | 87% | 3576 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 51,387 psi | 81% | 3560 fps | 99.8% |
| Alliant Reloder-26 | <<locked>> | 94% | 56,101 psi | 88% | 3668 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 57,276 psi | 90% | 3638 fps | 98.4% |
| Bofors RP3 | <<locked>> | 82% | 55,927 psi | 88% | 3514 fps | 100% |
| Bofors RP5 | <<locked>> | 96% | 54,708 psi | 86% | 3593 fps | 98.1% |
| Bofors RP7 | <<locked>> | 86% | 55,042 psi | 86% | 3494 fps | 98.7% |
| Hodgdon H380 | <<locked>> | 82% | 56,217 psi | 88% | 3530 fps | 99.9% |
| Hodgdon H414 | <<locked>> | 84% | 55,114 psi | 86% | 3563 fps | 99.1% |
| Hodgdon H4350 | <<locked>> | 88% | 55,274 psi | 87% | 3533 fps | 98.2% |
| Hodgdon H4831ᴾ | <<locked>> | 100% | 57,696 psi | 90% | 3579 fps | 96.8% |
| Hodgdon H4831 SC | <<locked>> | 96% | 57,696 psi | 90% | 3579 fps | 96.8% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 56,971 psi | 89% | 3530 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 50,372 psi | 79% | 3612 fps | 98.1% |
| Hodgdon Superformance | <<locked>> | 86% | 54,621 psi | 86% | 3576 fps | 98.9% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,709 psi | 58% | 2316 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 56,521 psi | 89% | 3517 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 56,202 psi | 88% | 3501 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 54,607 psi | 86% | 3468 fps | 99% |
| IMR 4350 | <<locked>> | 90% | 56,623 psi | 89% | 3530 fps | 99% |
| IMR 4451 Enduron | <<locked>> | 86% | 56,550 psi | 89% | 3524 fps | 99.2% |
| IMR 4831 | <<locked>> | 94% | 57,580 psi | 90% | 3563 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 56,057 psi | 88% | 3514 fps | 96.6% |
| IMR 7828 SSC | <<locked>> | 96% | 56,695 psi | 89% | 3645 fps | 97.4% |
| Lovex S062 | <<locked>> | 82% | 57,043 psi | 89% | 3504 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 57,029 psi | 89% | 3520 fps | 99.8% |
| Lovex S070 | <<locked>> | 88% | 55,201 psi | 87% | 3510 fps | 99.2% |
| Lovex S071ᴾ | <<locked>> | 100% | 52,214 psi | 82% | 3448 fps | 99.3% |
| Norma 204 | <<locked>> | 88% | 54,041 psi | 85% | 3520 fps | 97.6% |
| Norma MRP | <<locked>> | 94% | 54,375 psi | 85% | 3619 fps | 99.1% |
| Norma URP | <<locked>> | 88% | 54,360 psi | 85% | 3533 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 56,565 psi | 89% | 3645 fps | 97.7% |
| Ramshot Hunter | <<locked>> | 90% | 57,217 psi | 90% | 3596 fps | 99.7% |
| Ramshot Magnum | <<locked>> | 96% | 53,722 psi | 84% | 3540 fps | 98.7% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,289 psi | 58% | 2365 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 55,985 psi | 88% | 3510 fps | 99.5% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 57,551 psi | 90% | 3638 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 56,231 psi | 88% | 3576 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 54,534 psi | 85% | 3606 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 51,271 psi | 80% | 3612 fps | 99.2% |
| Rottweil R 903 | <<locked>> | 84% | 56,275 psi | 88% | 3510 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 54,737 psi | 86% | 3501 fps | 96.8% |
| Rottweil R 905 | <<locked>> | 94% | 55,753 psi | 87% | 3573 fps | 98.3% |
| Rottweil R 907 | <<locked>> | 86% | 55,042 psi | 86% | 3494 fps | 98.7% |
| Shooters World Long Rifle | <<locked>> | 88% | 57,029 psi | 89% | 3520 fps | 99.8% |
| Shooters World Precision | <<locked>> | 82% | 57,043 psi | 89% | 3504 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 55,201 psi | 87% | 3510 fps | 99.2% |
| SNPE Vectan SP 11 | <<locked>> | 82% | 54,099 psi | 85% | 3510 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 56,231 psi | 88% | 3373 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 56,840 psi | 89% | 3465 fps | 99.3% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 55,288 psi | 87% | 3566 fps | 98.2% |
| Somchem S355 | <<locked>> | 84% | 55,898 psi | 88% | 3507 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 56,565 psi | 89% | 3484 fps | 96.5% |
| Somchem S365 | <<locked>> | 90% | 54,491 psi | 85% | 3540 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 56,536 psi | 89% | 3543 fps | 98.9% |
| Unknown powder | <<locked>> | 86% | 54,766 psi | 86% | 3540 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 88% | 54,259 psi | 85% | 3428 fps | 100% |
| Vihtavuori N160 | <<locked>> | 86% | 55,187 psi | 86% | 3501 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 54,172 psi | 85% | 3478 fps | 98.4% |
| Vihtavuori N550 | <<locked>> | 86% | 55,637 psi | 87% | 3556 fps | 100% |
| Vihtavuori N555 | <<locked>> | 96% | 57,653 psi | 90% | 3606 fps | 100% |
| Vihtavuori N560 | <<locked>> | 96% | 54,853 psi | 86% | 3615 fps | 96.4% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 54,259 psi | 85% | 3570 fps | 96.6% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 56,420 psi | 88% | 3481 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 55,114 psi | 86% | 3563 fps | 99.1% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 56,782 psi | 89% | 3724 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 54,433 psi | 85% | 3491 fps | 97.9% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 26"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2700 | <<locked>> | 80% | 48,776 psi | 76% | 3310 fps | 97.5% |
| Accurate 3100 | <<locked>> | 84% | 35,984 psi | 56% | 3081 fps | 95.4% |
| Accurate 4350 | <<locked>> | 80% | 42,148 psi | 66% | 3274 fps | 98.7% |
| ADI AR 2208 | <<locked>> | 80% | 50,372 psi | 79% | 3402 fps | 99.9% |
| ADI AR 2209 | <<locked>> | 88% | 46,543 psi | 73% | 3389 fps | 96% |
| ADI AR 2213 | 68.7 gr | 94% | 51,184 psi | 80% | 3520 fps | 95.9% |
| ADI AR 2225 | <<locked>> | 98% | 38,130 psi | 60% | 3232 fps | 95.2% |
| Alliant Power Pro Varmint | <<locked>> | 86% | 43,816 psi | 69% | 3320 fps | 95.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 51,474 psi | 81% | 3435 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 40,408 psi | 63% | 3284 fps | 98.7% |
| Alliant Reloder-17 | <<locked>> | 80% | 46,862 psi | 73% | 3442 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 43,352 psi | 68% | 3310 fps | 95% |
| Alliant Reloder-22 | <<locked>> | 90% | 44,382 psi | 70% | 3373 fps | 95.6% |
| Alliant Reloder-23 | <<locked>> | 80% | 30,037 psi | 47% | 2979 fps | 96.7% |
| Alliant Reloder-25 | <<locked>> | 88% | 34,374 psi | 54% | 3130 fps | 95.4% |
| Alliant Reloder-26 | <<locked>> | 80% | 32,750 psi | 51% | 3114 fps | 95.4% |
| Bofors RP15 | <<locked>> | 92% | 43,772 psi | 69% | 3353 fps | 95.2% |
| Bofors RP3 | <<locked>> | 80% | 52,417 psi | 82% | 3448 fps | 100% |
| Bofors RP5 | <<locked>> | 90% | 44,382 psi | 70% | 3373 fps | 95.6% |
| Bofors RP7 | <<locked>> | 80% | 45,527 psi | 71% | 3294 fps | 96.8% |
| Hodgdon H380 | <<locked>> | 80% | 52,460 psi | 82% | 3461 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 80% | 47,993 psi | 75% | 3419 fps | 97.9% |
| Hodgdon H4350 | <<locked>> | 80% | 42,844 psi | 67% | 3264 fps | 95.2% |
| Hodgdon H4831 | <<locked>> | 96% | 50,488 psi | 79% | 3438 fps | 95% |
| Hodgdon H4831 SC | <<locked>> | 94% | 53,708 psi | 84% | 3504 fps | 95.9% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 37,985 psi | 60% | 3150 fps | 99.1% |
| Hodgdon Retumbo | <<locked>> | 96% | 43,932 psi | 69% | 3451 fps | 96.1% |
| Hodgdon Superformance | <<locked>> | 80% | 43,453 psi | 68% | 3340 fps | 96.5% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,383 psi | 43% | 2080 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 53,084 psi | 83% | 3455 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 49,458 psi | 78% | 3376 fps | 99.9% |
| IMR 4166 Enduron | <<locked>> | 80% | 48,399 psi | 76% | 3343 fps | 98% |
| IMR 4350 | <<locked>> | 80% | 40,944 psi | 64% | 3199 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 80% | 46,731 psi | 73% | 3327 fps | 97.5% |
| IMR 4831 | <<locked>> | 80% | 36,521 psi | 57% | 3114 fps | 97.4% |
| IMR 4955 Enduron | <<locked>> | 92% | 52,417 psi | 82% | 3445 fps | 95.8% |
| IMR 7828 SSC | <<locked>> | 92% | 49,066 psi | 77% | 3484 fps | 95.4% |
| Lovex S062 | <<locked>> | 80% | 53,592 psi | 84% | 3442 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 44,425 psi | 70% | 3268 fps | 98.2% |
| Lovex S070 | <<locked>> | 80% | 42,670 psi | 67% | 3241 fps | 96.8% |
| Lovex S071 | <<locked>> | 88% | 35,128 psi | 55% | 3058 fps | 95.1% |
| Norma 204 | <<locked>> | 84% | 46,978 psi | 74% | 3373 fps | 95.9% |
| Norma MRP | 64.9 gr | 86% | 40,625 psi | 64% | 3310 fps | 95.8% |
| Norma URP | <<locked>> | 80% | 41,582 psi | 65% | 3268 fps | 98.5% |
| Ramshot Grand | <<locked>> | 90% | 48,443 psi | 76% | 3481 fps | 95.7% |
| Ramshot Hunter | <<locked>> | 80% | 40,509 psi | 63% | 3245 fps | 96.8% |
| Ramshot Magnum | <<locked>> | 90% | 42,409 psi | 66% | 3301 fps | 95.9% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,963 psi | 44% | 2129 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 52,373 psi | 82% | 3442 fps | 99.1% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 49,719 psi | 78% | 3504 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 42,192 psi | 66% | 3294 fps | 98.5% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 40,640 psi | 64% | 3304 fps | 98.1% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 38,130 psi | 60% | 3268 fps | 95% |
| Rottweil R 903 | <<locked>> | 80% | 49,168 psi | 77% | 3383 fps | 100% |
| Rottweil R 904 | <<locked>> | 88% | 47,906 psi | 75% | 3363 fps | 95.1% |
| Rottweil R 905 | <<locked>> | 88% | 45,426 psi | 71% | 3360 fps | 95.9% |
| Rottweil R 907 | <<locked>> | 80% | 45,527 psi | 71% | 3294 fps | 96.8% |
| Shooters World Long Rifle | <<locked>> | 80% | 44,425 psi | 70% | 3268 fps | 98.2% |
| Shooters World Precision | <<locked>> | 80% | 53,592 psi | 84% | 3442 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 42,670 psi | 67% | 3241 fps | 96.8% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 50,517 psi | 79% | 3442 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 49,632 psi | 78% | 3264 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 43,584 psi | 68% | 3199 fps | 97% |
| SNPE Vectan Tubal 8000 | <<locked>> | 88% | 45,034 psi | 71% | 3353 fps | 95.8% |
| Somchem S355 | <<locked>> | 80% | 49,197 psi | 77% | 3383 fps | 100% |
| Somchem S361 | <<locked>> | 90% | 52,924 psi | 83% | 3419 fps | 95.7% |
| Somchem S365 | <<locked>> | 80% | 38,247 psi | 60% | 3212 fps | 99.8% |
| Somchem S385 | <<locked>> | 84% | 40,422 psi | 63% | 3202 fps | 95.2% |
| Unknown powder | <<locked>> | 80% | 44,570 psi | 70% | 3333 fps | 98.7% |
| Vihtavuori N150 | <<locked>> | 80% | 42,221 psi | 66% | 3196 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 44,759 psi | 70% | 3297 fps | 99.1% |
| Vihtavuori N165 | <<locked>> | 90% | 41,466 psi | 65% | 3209 fps | 95.2% |
| Vihtavuori N550 | <<locked>> | 80% | 45,498 psi | 71% | 3353 fps | 99.1% |
| Vihtavuori N555 | <<locked>> | 80% | 33,547 psi | 53% | 3074 fps | 96.8% |
| Vihtavuori N560 | 69.4 gr | 94% | 51,082 psi | 80% | 3540 fps | 95.5% |
| Vihtavuori N565 | <<locked>> | 98% | 50,502 psi | 79% | 3494 fps | 95.7% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 42,264 psi | 66% | 3219 fps | 99.9% |
| Winchester 760 | <<locked>> | 80% | 47,993 psi | 75% | 3419 fps | 97.9% |
| Winchester StaBALL HD | <<locked>> | 80% | 26,672 psi | 42% | 2936 fps | 95.5% |
| Winchester Supreme 780 | <<locked>> | 86% | 43,598 psi | 68% | 3268 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 80 powders for .257 Weath. Mag. loaded with the .257 | 87gr | Remington HP Power-Lokt. Winchester StaBALL HD delivers the highest muzzle velocity at 3,724 fps; across all powders the maximum-charge window runs from 2,316 fps to 3,724 fps. ADI AR 2225 gives the best case fill at 100 %, and 80 of the 80 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (440 MPa), the top charges use 58–90 %, leaving at least 10 % headroom. The 87.0 gr projectile in 0.257" calls for a 1:10.5 twist; slower twists will usually not stabilise this weight. ADI AR 2225, Alliant Reloder-25, Bofors RP15 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. Vihtavuori N560, Norma MRP, ADI AR 2213 rank at the top here: for .257 Weath. Mag. with the .257 | 87gr | Remington HP Power-Lokt 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.