Load Specifications
Load data in caliber 6.5 x 52 R with .257 | 86gr | Winchester SPRN bullet and 6 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant AR-Comp, ReloadSwiss RS 14 and Hodgdon TrailBoss.
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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Max Load - Barrel Length: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 98% | 31,618 psi | 89% | 2582 fps | 96.1% |
| Alliant AR-Comp | <<locked>> | 90% | 31,038 psi | 87% | 2556 fps | 97.8% |
| Alliant Reloder-10x | <<locked>> | 82% | 30,284 psi | 85% | 2477 fps | 96.3% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 31,473 psi | 89% | 1719 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 31,314 psi | 88% | 1762 fps | 100% |
| Vihtavuori N130 | <<locked>> | 84% | 31,372 psi | 88% | 2448 fps | 96.3% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 23.62"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2495 | <<locked>> | 96% | 29,660 psi | 83% | 2533 fps | 95.3% |
| Alliant AR-Comp | 22.4 gr | 84% | 25,846 psi | 73% | 2398 fps | 95.3% |
| Alliant Reloder-10x | <<locked>> | 80% | 28,500 psi | 80% | 2428 fps | 95.5% |
| Hodgdon TrailBoss | 7.4 gr | 80% | 22,945 psi | 65% | 1532 fps | 100% |
| ReloadSwiss RS 14 | 7.6 gr | 80% | 22,974 psi | 65% | 1575 fps | 100% |
| Vihtavuori N130 | <<locked>> | 82% | 29,254 psi | 82% | 2392 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 6 powders for 6.5 x 52 R loaded with the .257 | 86gr | Winchester SPRN. Accurate 2495 delivers the highest muzzle velocity at 2,582 fps; across all powders the maximum-charge window runs from 1,719 fps to 2,582 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 6 of the 6 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (245 MPa), the top charges use 85–89 %, leaving at least 11 % headroom. The 86.0 gr projectile in 0.257" calls for a 1:10.5 twist; slower twists will usually not stabilise this weight. Hodgdon TrailBoss, ReloadSwiss RS 14 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. Alliant AR-Comp, ReloadSwiss RS 14, Hodgdon TrailBoss rank at the top here: for 6.5 x 52 R with the .257 | 86gr | Winchester SPRN 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.