Load Specifications
Load data in caliber .300 HAM'R with .308 | 125gr | Sierra Tipped GameKing bullet and 1 powder. The key underlying parameters are shown in the table above.
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: 16"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| ADI APS 450ᴾ | <<locked>> | 100% | 29,530 psi | 51% | 666 fps | 100% |
Start Load - Barrel Length: 16"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| ADI APS 450 | <<locked>> | 80% | 18,623 psi | 32% | 587 fps | 100% |
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 1 powders for .300 HAM'R loaded with the .308 | 125gr | Sierra Tipped GameKing. ADI APS 450 delivers the highest muzzle velocity at 666 fps; across all powders the maximum-charge window runs from 666 fps to 666 fps. ADI APS 450 gives the best case fill at 100 %, and 1 of the 1 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (396 MPa), the top charges use 51–51 %, leaving at least 49 % headroom. The 125.0 gr projectile in 0.308" calls for a 1:13.5 twist; slower twists will usually not stabilise this weight. ADI APS 450 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. ADI APS 450 stay subsonic at start load. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.