Load data for .45 Colt + .451 | 185gr | Speer TMJ-M

.45 Colt cartridge drawing
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Load Specifications

Bullet Manufacturer:Speer
Bullet Weight:185 gr
Bullet Diameter:0.451"
Bullet Length:<<locked>>
Case Length (l3):1.266"
Cartridge Length (C.O.L.):<<locked>>
Case Capacity:41.6 Grains of Water
Primer Size:Large Pistol Magnum (LPM)
Barrel Length:5.5"
Max. allowed Pressure:15,954 psi

Load data in caliber .45 Colt with .451 | 185gr | Speer TMJ-M bullet and 3 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are 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 ≥ 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"

PowderChargeFRMaxP%V(0)z
Hodgdon TrailBoss<<locked>>92%14,243 psi89%1001 fps100%
ReloadSwiss RS 14<<locked>>96%14,069 psi88%1030 fps100%
Vihtavuori N32C Tin Star²<<locked>>64%14,011 psi88%981 fps100%

Recommended = one of the top powders for this cartridge and bullet combination.

Start Load - Barrel Length: 5.5"

PowderChargeFRMaxP%V(0)z
Hodgdon TrailBoss²5.9 gr60%7,585 psi48%781 fps99.9%
ReloadSwiss RS 14²6 gr60%7,107 psi45%774 fps97.5%
Vihtavuori N32C Tin Star²<<locked>>60%12,720 psi80%948 fps100%

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.

<<locked>> you need an access license to unlock this data.

This overview compares 2 powders for .45 Colt loaded with the .451 | 185gr | Speer TMJ-M. ReloadSwiss RS 14 delivers the highest muzzle velocity at 1,030 fps; across all powders the maximum-charge window runs from 1,001 fps to 1,030 fps. ReloadSwiss RS 14 gives the best case fill at 96 %, and 2 of the 2 powders fall inside the usable 80–100 % fill window.

Relative to the caliber's maximum pressure (110 MPa), the top charges use 88–89 %, leaving at least 11 % headroom. ReloadSwiss RS 14, Hodgdon TrailBoss rank at the top here: for .45 Colt with the .451 | 185gr | Speer TMJ-M they combine a high case fill with complete burn and sit in the upper velocity band. Hodgdon TrailBoss, ReloadSwiss RS 14 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.

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