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30 Thompson Center Load Data & Ballistics Calculator

Estimate chamber pressure and muzzle velocity for the 30 Thompson Center with the free, in-browser MyLoads internal-ballistics simulator. The figures below are illustrative estimates from a physics model — not a recommended recipe. Always cross-check a current published loading manual.

30 Thompson Center reference

Maximum average pressure (MAP)62,000 psi
Nominal case capacity54.0 gr H₂O
Groove / bullet diameter0.308 in (7.82 mm)

Example simulation illustrative

Bullet
Hornady 0.308 165 gr GMX
Powder
Hodgdon H4895
Charge
39.7 gr
Barrel
26 in

Muzzle velocity

2,491 fps

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

37,042 – 45,391 – 54,675 psi

nominal is 73% of the 62,000 psi maximum average pressure

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

Use MyLoads as a 30 Thompson Center 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 30 Thompson Center in the MyLoads calculator →

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