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10mm Automatic Load Data & Ballistics Calculator

Estimate chamber pressure and muzzle velocity for the 10mm Automatic with the free, in-browser MyLoads internal ballistics simulator. The figures below are illustrative estimates from a physics model — not a recommended load. Always cross-check a current published loading manual.

10mm Automatic reference

Maximum average pressure (MAP)37,500 psi
Nominal case capacity24.2 gr H₂O
Groove / bullet diameter0.400 in (10.16 mm)

Example simulation illustrative

Bullet
Hornady 0.400 180 gr XTP
Powder
Accurate No. 9
Charge
12.2 gr
Barrel
5 in

Muzzle velocity

1,175 fps

Peak chamber pressure (interval, ±10% burn rate)

19,025 – 25,592 – 33,590 psi

nominal is 68% MAP (37,500 psi)

The simulator isn't optimized for this cartridge yet and may read pressure high.

Illustrative example — every figure is an estimate; always confirm your load against a current published manual before loading.

Popular 10mm Automatic powders

Powders and bullets handloaders commonly use for the 10mm Automatic, drawn from public discussion and listed most common first. They appear as the Popular group in the calculator's pickers. This is not a load recommendation — always check your load against a current published manual.

Popular 10mm Automatic bullets

Use MyLoads as a 10mm Automatic velocity and pressure calculator: it estimates muzzle velocity, muzzle energy and the full chamber-pressure curve for your own powder, charge and barrel length, compared against the reference facts above.

Open the 10mm Automatic in the MyLoads calculator →

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