Load Specifications
Load data in caliber .45 Colt with .452 | 255gr | LEE Mold 452-255-RF bullet and 3 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Hodgdon TrailBoss and ReloadSwiss RS 14.
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 ≥ 60% and propellant combustion ≥ 80%. 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: 5.5"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Hodgdon TrailBoss | <<locked>> | 92% | 14,127 psi | 89% | 823 fps | 100% |
| ReloadSwiss RS 14 | <<locked>> | 96% | 13,692 psi | 86% | 843 fps | 100% |
| Vihtavuori N32C Tin Star² | <<locked>> | 64% | 13,938 psi | 87% | 804 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 5.5"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Hodgdon TrailBoss² | 5.1 gr | 60% | 7,049 psi | 44% | 640 fps | 100% |
| ReloadSwiss RS 14² | 5.1 gr | 60% | 6,179 psi | 39% | 620 fps | 98.6% |
| Vihtavuori N32C Tin Star² | <<locked>> | 60% | 12,299 psi | 77% | 771 fps | 100% |
Recommended = one of the top powders for this cartridge and bullet combination.
² fill rate low - you might want to consider using a filler to ensure proper ignition.
This overview compares 3 powders for .45 Colt loaded with the .452 | 255gr | LEE Mold 452-255-RF. ReloadSwiss RS 14 delivers the highest muzzle velocity at 843 fps; across all powders the maximum-charge window runs from 804 fps to 843 fps. ReloadSwiss RS 14 gives the best case fill at 96 %, and 2 of the 3 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (110 MPa), the top charges use 86–89 %, leaving at least 11 % headroom. Hodgdon TrailBoss, ReloadSwiss RS 14 rank at the top here: for .45 Colt with the .452 | 255gr | LEE Mold 452-255-RF they combine a high case fill with complete burn and sit in the upper velocity band. Hodgdon TrailBoss, ReloadSwiss RS 14, Vihtavuori N32C Tin Star 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.