Load Specifications
Load data in caliber 6.5 x 52 R with .257 | 87gr | Speer TNT bullet and 8 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>> | 96% | 31,676 psi | 89% | 2582 fps | 96.5% |
| Alliant AR-Comp | <<locked>> | 88% | 30,632 psi | 86% | 2549 fps | 98.1% |
| Alliant Reloder-10x | <<locked>> | 82% | 31,575 psi | 89% | 2510 fps | 97.2% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 31,676 psi | 89% | 1729 fps | 100% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 31,546 psi | 89% | 1768 fps | 100% |
| Vihtavuori N130 | <<locked>> | 82% | 30,748 psi | 87% | 2431 fps | 96.5% |
| Vihtavuori N133 | <<locked>> | 88% | 31,966 psi | 90% | 2470 fps | 95.8% |
| Vihtavuori N135 | <<locked>> | 94% | 31,502 psi | 89% | 2546 fps | 96% |
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>> | 94% | 29,472 psi | 83% | 2526 fps | 95.7% |
| Alliant AR-Comp | 22.6 gr | 82% | 25,338 psi | 71% | 2385 fps | 95.6% |
| Alliant Reloder-10x | <<locked>> | 80% | 29,820 psi | 84% | 2464 fps | 96.5% |
| Hodgdon TrailBoss | 7.7 gr | 80% | 23,380 psi | 66% | 1545 fps | 100% |
| ReloadSwiss RS 14 | 7.8 gr | 80% | 23,018 psi | 65% | 1578 fps | 100% |
| Vihtavuori N130 | <<locked>> | 80% | 29,051 psi | 82% | 2385 fps | 95.9% |
| Vihtavuori N133 | <<locked>> | 86% | 30,269 psi | 85% | 2425 fps | 95.1% |
| Vihtavuori N135 | <<locked>> | 92% | 29,762 psi | 84% | 2500 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 21 powders for 6.5 x 52 R loaded with the .257 | 87gr | Speer TNT. Accurate 2495 delivers the highest muzzle velocity at 2,582 fps; across all powders the maximum-charge window runs from 1,729 fps to 2,582 fps. Hodgdon TrailBoss gives the best case fill at 100 %, and 21 of the 21 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (245 MPa), the top charges use 86–90 %, leaving at least 10 % headroom. The 87.0 gr projectile in 0.257" calls for a 1:12.0 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 | 87gr | Speer TNT they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate 2460, Accurate 4064, Hodgdon H322 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.