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8x57 IRS Load Data & Ballistics Calculator

Estimate chamber pressure and muzzle velocity for the 8x57 IRS 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.

8x57 IRS reference

Maximum average pressure (MAP)3,300 BAR
Nominal case capacity63.0 gr H₂O
Groove / bullet diameter0.323 in (8.20 mm)

Example simulation illustrative

Bullet
Hornady 0.323 180 gr GMX
Powder
Reload Swiss RS 50
Charge
44.1 gr
Barrel
25.5 in

Muzzle velocity

2,386 fps

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

27,444 – 36,517 – 46,746 psi

nominal is 76% MAP (47,862 psi)

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 8x57 IRS powders

Powders and bullets handloaders commonly use for the 8x57 IRS, 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 8x57 IRS bullets

Use MyLoads as a 8x57 IRS 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 8x57 IRS in the MyLoads calculator →

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