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300 Lapua Magnum Load Data & Ballistics Calculator

Estimate chamber pressure and muzzle velocity for the 300 Lapua Magnum 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.

300 Lapua Magnum reference

Maximum average pressure (MAP)4,400 BAR
Nominal case capacity113.3 gr H₂O
Groove / bullet diameter0.308 in (7.82 mm)

Example simulation illustrative

Bullet
Sierra 30 Caliber (.308) 220 gr HPBT MatchKing
Powder
Vihtavuori 24N41
Charge
83.1 gr
Barrel
27 in

Muzzle velocity

2,684 fps

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

38,187 – 48,328 – 59,696 psi

nominal is 76% MAP (63,817 psi)

Pressure for this powder is extrapolated from a velocity-only fit — the pressure figures carry extra uncertainty in both directions.

The simulator isn't optimized for this cartridge yet: there isn't enough published pressure data to check it.

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

Popular 300 Lapua Magnum powders

Powders and bullets handloaders commonly use for the 300 Lapua Magnum, 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 300 Lapua Magnum bullets

Use MyLoads as a 300 Lapua Magnum 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 300 Lapua Magnum in the MyLoads calculator →

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