Load Specifications
Load data in caliber .257 Weath. Mag. with .257 | 91gr | Peregrine VLR5 (VLR-5) bullet and 84 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Norma MRP, Vihtavuori N560 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% | 55,550 psi | 87% | 3389 fps | 98.9% |
| Accurate 3100 | <<locked>> | 96% | 54,027 psi | 85% | 3428 fps | 99.7% |
| Accurate 4064 | <<locked>> | 82% | 57,000 psi | 89% | 3422 fps | 100% |
| Accurate 4350 | <<locked>> | 88% | 55,245 psi | 87% | 3488 fps | 100% |
| ADI AR 2208 | <<locked>> | 84% | 56,927 psi | 89% | 3465 fps | 100% |
| ADI AR 2209 | <<locked>> | 94% | 56,927 psi | 89% | 3550 fps | 98.6% |
| ADI AR 2213 | <<locked>> | 96% | 54,621 psi | 86% | 3537 fps | 97.2% |
| ADI AR 2225ᴾ | <<locked>> | 100% | 40,364 psi | 63% | 3258 fps | 96.8% |
| Alliant Reloder- TS 15.5 | <<locked>> | 82% | 54,476 psi | 85% | 3428 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 90% | 56,449 psi | 88% | 3563 fps | 100% |
| Alliant Reloder-17 | <<locked>> | 84% | 53,853 psi | 84% | 3514 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 94% | 56,188 psi | 88% | 3530 fps | 98.5% |
| Alliant Reloder-22 | <<locked>> | 96% | 54,259 psi | 85% | 3533 fps | 98.3% |
| Alliant Reloder-23 | <<locked>> | 98% | 55,274 psi | 87% | 3517 fps | 100% |
| Alliant Reloder-25ᴾ | <<locked>> | 100% | 51,024 psi | 80% | 3501 fps | 99.9% |
| Alliant Reloder-26 | <<locked>> | 94% | 55,709 psi | 87% | 3606 fps | 100% |
| Bofors RP15ᴾ | <<locked>> | 100% | 56,913 psi | 89% | 3579 fps | 98.7% |
| Bofors RP3 | <<locked>> | 82% | 55,448 psi | 87% | 3448 fps | 100% |
| Bofors RP5 | <<locked>> | 96% | 54,259 psi | 85% | 3533 fps | 98.3% |
| Bofors RP7 | <<locked>> | 86% | 54,766 psi | 86% | 3432 fps | 98.9% |
| Hodgdon H1000ᴾ | <<locked>> | 100% | 46,717 psi | 73% | 3356 fps | 96.1% |
| Hodgdon H380 | <<locked>> | 82% | 55,622 psi | 87% | 3465 fps | 100% |
| Hodgdon H414 | <<locked>> | 84% | 54,766 psi | 86% | 3501 fps | 99.3% |
| Hodgdon H4350 | <<locked>> | 88% | 55,172 psi | 86% | 3478 fps | 98.5% |
| Hodgdon H4831ᴾ | <<locked>> | 100% | 57,638 psi | 90% | 3524 fps | 97.1% |
| Hodgdon H4831 SC | <<locked>> | 96% | 57,348 psi | 90% | 3520 fps | 97.1% |
| Hodgdon Hybrid 100V | <<locked>> | 92% | 56,898 psi | 89% | 3471 fps | 100% |
| Hodgdon LEVERevolution | <<locked>> | 82% | 57,566 psi | 90% | 3510 fps | 100% |
| Hodgdon Retumboᴾ | <<locked>> | 100% | 49,980 psi | 78% | 3553 fps | 98.4% |
| Hodgdon Superformance | <<locked>> | 86% | 54,476 psi | 85% | 3520 fps | 99.1% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 36,492 psi | 57% | 2264 fps | 100% |
| Hodgdon VARGET | <<locked>> | 82% | 56,550 psi | 89% | 3458 fps | 100% |
| IMR 4064 | <<locked>> | 84% | 55,927 psi | 88% | 3438 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 84% | 54,607 psi | 86% | 3412 fps | 99.2% |
| IMR 4350 | <<locked>> | 90% | 56,391 psi | 88% | 3474 fps | 99.2% |
| IMR 4451 Enduron | <<locked>> | 86% | 56,463 psi | 88% | 3468 fps | 99.4% |
| IMR 4831 | <<locked>> | 94% | 57,130 psi | 90% | 3501 fps | 100% |
| IMR 4955 Enduron | <<locked>> | 94% | 55,898 psi | 88% | 3461 fps | 96.9% |
| IMR 7828 SSC | <<locked>> | 96% | 56,405 psi | 88% | 3583 fps | 97.6% |
| Lovex S062 | <<locked>> | 82% | 56,637 psi | 89% | 3435 fps | 100% |
| Lovex S065 | <<locked>> | 88% | 56,782 psi | 89% | 3461 fps | 99.9% |
| Lovex S070 | <<locked>> | 88% | 54,897 psi | 86% | 3448 fps | 99.4% |
| Lovex S071ᴾ | <<locked>> | 100% | 51,401 psi | 81% | 3383 fps | 99.4% |
| Norma 203B | <<locked>> | 82% | 57,638 psi | 90% | 3501 fps | 100% |
| Norma 204 | <<locked>> | 88% | 53,751 psi | 84% | 3465 fps | 97.9% |
| Norma MRP | <<locked>> | 94% | 53,925 psi | 85% | 3553 fps | 99.2% |
| Norma URP | <<locked>> | 88% | 54,143 psi | 85% | 3474 fps | 100% |
| Ramshot Grand | <<locked>> | 94% | 56,333 psi | 88% | 3593 fps | 98% |
| Ramshot Hunter | <<locked>> | 90% | 56,985 psi | 89% | 3537 fps | 99.8% |
| Ramshot Magnum | <<locked>> | 96% | 53,214 psi | 83% | 3484 fps | 98.9% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 37,246 psi | 58% | 2316 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 82% | 55,506 psi | 87% | 3445 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 84% | 57,305 psi | 90% | 3573 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 88% | 55,579 psi | 87% | 3510 fps | 100% |
| ReloadSwiss RS 70 | <<locked>> | 88% | 54,099 psi | 85% | 3543 fps | 100% |
| ReloadSwiss RS 76ᴾ | <<locked>> | 100% | 50,734 psi | 80% | 3550 fps | 99.4% |
| Rottweil R 903 | <<locked>> | 84% | 55,564 psi | 87% | 3442 fps | 100% |
| Rottweil R 904 | <<locked>> | 92% | 54,476 psi | 85% | 3448 fps | 97.2% |
| Rottweil R 905 | <<locked>> | 94% | 55,506 psi | 87% | 3514 fps | 98.5% |
| Rottweil R 907 | <<locked>> | 86% | 54,766 psi | 86% | 3432 fps | 98.9% |
| Shooters World Long Rifle | <<locked>> | 88% | 56,782 psi | 89% | 3461 fps | 99.9% |
| Shooters World Precision | <<locked>> | 82% | 56,637 psi | 89% | 3435 fps | 100% |
| Shooters World SW4350 | <<locked>> | 88% | 54,897 psi | 86% | 3448 fps | 99.4% |
| SNPE Vectan SP 11 | <<locked>> | 84% | 57,522 psi | 90% | 3510 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 84% | 55,898 psi | 88% | 3310 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 88% | 56,376 psi | 88% | 3406 fps | 99.4% |
| SNPE Vectan Tubal 8000 | <<locked>> | 94% | 55,056 psi | 86% | 3507 fps | 98.4% |
| Somchem S355 | <<locked>> | 84% | 55,492 psi | 87% | 3442 fps | 100% |
| Somchem S361 | <<locked>> | 92% | 56,405 psi | 88% | 3432 fps | 96.9% |
| Somchem S365 | <<locked>> | 90% | 54,085 psi | 85% | 3474 fps | 100% |
| Somchem S385 | <<locked>> | 94% | 55,956 psi | 88% | 3481 fps | 99.1% |
| Unknown powder | <<locked>> | 86% | 54,331 psi | 85% | 3478 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 86% | 56,797 psi | 89% | 3406 fps | 100% |
| Vihtavuori N160 | <<locked>> | 88% | 55,898 psi | 88% | 3465 fps | 100% |
| Vihtavuori N165 | <<locked>> | 98% | 55,869 psi | 88% | 3455 fps | 98.9% |
| Vihtavuori N540 | <<locked>> | 82% | 57,450 psi | 90% | 3402 fps | 100% |
| Vihtavuori N550 | <<locked>> | 88% | 55,216 psi | 87% | 3468 fps | 100% |
| Vihtavuori N555 | <<locked>> | 96% | 57,261 psi | 90% | 3547 fps | 100% |
| Vihtavuori N560 | <<locked>> | 94% | 53,925 psi | 85% | 3543 fps | 96.6% |
| Vihtavuori N565ᴾ | <<locked>> | 100% | 53,548 psi | 84% | 3504 fps | 96.8% |
| Winchester 6.5 StaBALL | <<locked>> | 88% | 56,014 psi | 88% | 3419 fps | 100% |
| Winchester 760 | <<locked>> | 84% | 54,766 psi | 86% | 3501 fps | 99.3% |
| Winchester StaBALL HDᴾ | <<locked>> | 100% | 56,608 psi | 89% | 3661 fps | 100% |
| Winchester Supreme 780 | <<locked>> | 92% | 54,244 psi | 85% | 3438 fps | 98.2% |
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% | 48,414 psi | 76% | 3255 fps | 97.7% |
| Accurate 3100 | <<locked>> | 84% | 35,259 psi | 55% | 3015 fps | 95.6% |
| Accurate 4064 | <<locked>> | 80% | 53,359 psi | 84% | 3363 fps | 100% |
| Accurate 4350 | <<locked>> | 80% | 41,466 psi | 65% | 3209 fps | 98.9% |
| ADI AR 2208 | <<locked>> | 80% | 50,256 psi | 79% | 3343 fps | 100% |
| ADI AR 2209 | <<locked>> | 86% | 43,091 psi | 68% | 3261 fps | 95.3% |
| ADI AR 2213 | 66.3 gr | 92% | 47,398 psi | 74% | 3386 fps | 95.3% |
| ADI AR 2225 | <<locked>> | 98% | 37,753 psi | 59% | 3179 fps | 95.6% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 51,024 psi | 80% | 3369 fps | 100% |
| Alliant Reloder-16 | <<locked>> | 80% | 40,016 psi | 63% | 3222 fps | 98.9% |
| Alliant Reloder-17 | <<locked>> | 80% | 46,369 psi | 73% | 3373 fps | 100% |
| Alliant Reloder-19 | <<locked>> | 86% | 42,873 psi | 67% | 3251 fps | 95.4% |
| Alliant Reloder-22 | <<locked>> | 90% | 43,961 psi | 69% | 3314 fps | 95.9% |
| Alliant Reloder-23 | <<locked>> | 80% | 29,443 psi | 46% | 2917 fps | 96.8% |
| Alliant Reloder-25 | <<locked>> | 88% | 33,794 psi | 53% | 3068 fps | 95.7% |
| Alliant Reloder-26 | <<locked>> | 80% | 32,053 psi | 50% | 3048 fps | 95.6% |
| Bofors RP15 | <<locked>> | 92% | 43,352 psi | 68% | 3294 fps | 95.5% |
| Bofors RP3 | <<locked>> | 80% | 51,851 psi | 81% | 3383 fps | 100% |
| Bofors RP5 | <<locked>> | 90% | 43,961 psi | 69% | 3314 fps | 95.9% |
| Bofors RP7 | <<locked>> | 80% | 45,020 psi | 71% | 3232 fps | 97% |
| Hodgdon H1000 | <<locked>> | 98% | 43,569 psi | 68% | 3281 fps | 95% |
| Hodgdon H380 | <<locked>> | 80% | 52,054 psi | 82% | 3399 fps | 99.8% |
| Hodgdon H414 | <<locked>> | 80% | 47,500 psi | 74% | 3356 fps | 98.1% |
| Hodgdon H4350 | <<locked>> | 80% | 42,453 psi | 67% | 3205 fps | 95.5% |
| Hodgdon H4831 | <<locked>> | 96% | 50,241 psi | 79% | 3386 fps | 95.4% |
| Hodgdon H4831 SC | <<locked>> | 92% | 49,777 psi | 78% | 3373 fps | 95.2% |
| Hodgdon Hybrid 100V | <<locked>> | 80% | 37,666 psi | 59% | 3094 fps | 99.3% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 53,911 psi | 84% | 3451 fps | 100% |
| Hodgdon Retumbo | <<locked>> | 94% | 40,567 psi | 64% | 3314 fps | 95.2% |
| Hodgdon Superformance | <<locked>> | 80% | 43,033 psi | 67% | 3281 fps | 96.8% |
| Hodgdon TrailBoss | <<locked>> | 80% | 27,195 psi | 43% | 2031 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 52,982 psi | 83% | 3396 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 49,240 psi | 77% | 3317 fps | 100% |
| IMR 4166 Enduron | <<locked>> | 80% | 48,022 psi | 75% | 3281 fps | 98.2% |
| IMR 4350 | <<locked>> | 80% | 40,553 psi | 64% | 3136 fps | 95.7% |
| IMR 4451 Enduron | <<locked>> | 80% | 46,601 psi | 73% | 3271 fps | 97.8% |
| IMR 4831 | <<locked>> | 80% | 35,882 psi | 56% | 3051 fps | 97.5% |
| IMR 4955 Enduron | <<locked>> | 90% | 48,921 psi | 77% | 3323 fps | 95.3% |
| IMR 7828 SSC | <<locked>> | 92% | 48,834 psi | 77% | 3428 fps | 95.8% |
| Lovex S062 | <<locked>> | 80% | 53,069 psi | 83% | 3376 fps | 100% |
| Lovex S065 | <<locked>> | 80% | 43,874 psi | 69% | 3205 fps | 98.4% |
| Lovex S070 | <<locked>> | 80% | 42,119 psi | 66% | 3182 fps | 97% |
| Lovex S071 | <<locked>> | 88% | 34,185 psi | 54% | 2986 fps | 95.1% |
| Norma 203B | <<locked>> | 80% | 53,751 psi | 84% | 3435 fps | 100% |
| Norma 204 | <<locked>> | 82% | 43,497 psi | 68% | 3245 fps | 95.3% |
| Norma MRP | 64 gr | 86% | 40,147 psi | 63% | 3251 fps | 96.1% |
| Norma URP | <<locked>> | 80% | 41,075 psi | 64% | 3202 fps | 98.7% |
| Ramshot Grand | <<locked>> | 90% | 47,979 psi | 75% | 3422 fps | 96% |
| Ramshot Hunter | <<locked>> | 80% | 40,118 psi | 63% | 3182 fps | 97.1% |
| Ramshot Magnum | <<locked>> | 90% | 41,858 psi | 66% | 3241 fps | 96.2% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 27,760 psi | 44% | 2080 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 80% | 51,837 psi | 81% | 3379 fps | 99.2% |
| ReloadSwiss RS 60 | <<locked>> | 80% | 49,284 psi | 77% | 3435 fps | 100% |
| ReloadSwiss RS 62 | <<locked>> | 80% | 41,727 psi | 65% | 3232 fps | 98.7% |
| ReloadSwiss RS 70 | <<locked>> | 80% | 40,321 psi | 63% | 3245 fps | 98.3% |
| ReloadSwiss RS 76 | <<locked>> | 92% | 37,507 psi | 59% | 3209 fps | 95.2% |
| Rottweil R 903 | <<locked>> | 80% | 48,559 psi | 76% | 3317 fps | 100% |
| Rottweil R 904 | <<locked>> | 88% | 47,732 psi | 75% | 3307 fps | 95.5% |
| Rottweil R 905 | <<locked>> | 86% | 41,959 psi | 66% | 3228 fps | 95.2% |
| Rottweil R 907 | <<locked>> | 80% | 45,020 psi | 71% | 3232 fps | 97% |
| Shooters World Long Rifle | <<locked>> | 80% | 43,874 psi | 69% | 3205 fps | 98.4% |
| Shooters World Precision | <<locked>> | 80% | 53,069 psi | 83% | 3376 fps | 100% |
| Shooters World SW4350 | <<locked>> | 80% | 42,119 psi | 66% | 3182 fps | 97% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 50,241 psi | 79% | 3383 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 49,211 psi | 77% | 3202 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 80% | 43,076 psi | 68% | 3140 fps | 97.2% |
| SNPE Vectan Tubal 8000 | <<locked>> | 86% | 41,582 psi | 65% | 3219 fps | 95% |
| Somchem S355 | <<locked>> | 80% | 48,660 psi | 76% | 3317 fps | 100% |
| Somchem S361 | <<locked>> | 88% | 48,979 psi | 77% | 3287 fps | 95.1% |
| Somchem S365 | <<locked>> | 80% | 37,739 psi | 59% | 3146 fps | 99.9% |
| Somchem S385 | <<locked>> | 84% | 39,740 psi | 62% | 3136 fps | 95.4% |
| Unknown powder | <<locked>> | 80% | 44,164 psi | 69% | 3271 fps | 98.9% |
| Vihtavuori N150 | <<locked>> | 80% | 46,557 psi | 73% | 3228 fps | 100% |
| Vihtavuori N160 | <<locked>> | 80% | 42,511 psi | 67% | 3202 fps | 99% |
| Vihtavuori N165 | <<locked>> | 90% | 42,380 psi | 66% | 3186 fps | 96% |
| Vihtavuori N540 | <<locked>> | 80% | 53,940 psi | 85% | 3350 fps | 100% |
| Vihtavuori N550 | <<locked>> | 80% | 42,076 psi | 66% | 3202 fps | 98.8% |
| Vihtavuori N555 | <<locked>> | 80% | 32,808 psi | 51% | 3005 fps | 96.9% |
| Vihtavuori N560 | 68.4 gr | 92% | 50,096 psi | 79% | 3465 fps | 95.6% |
| Vihtavuori N565 | <<locked>> | 98% | 49,980 psi | 78% | 3435 fps | 96% |
| Winchester 6.5 StaBALL | <<locked>> | 80% | 41,989 psi | 66% | 3163 fps | 100% |
| Winchester 760 | <<locked>> | 80% | 47,500 psi | 74% | 3356 fps | 98.1% |
| Winchester StaBALL HD | <<locked>> | 80% | 26,034 psi | 41% | 2874 fps | 95.6% |
| Winchester Supreme 780 | <<locked>> | 86% | 43,163 psi | 68% | 3212 fps | 95.5% |
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 84 powders for .257 Weath. Mag. loaded with the .257 | 91gr | Peregrine VLR5 (VLR-5). Winchester StaBALL HD delivers the highest muzzle velocity at 3,661 fps; across all powders the maximum-charge window runs from 2,264 fps to 3,661 fps. ADI AR 2225 gives the best case fill at 100 %, and 84 of the 84 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 91.0 gr projectile in 0.257" calls for a 1:9.5 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. Norma MRP, Vihtavuori N560, ADI AR 2213 rank at the top here: for .257 Weath. Mag. with the .257 | 91gr | Peregrine VLR5 (VLR-5) 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.