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8.6 Blackout Load Data & Ballistics Calculator

Estimate chamber pressure and muzzle velocity for the 8.6 Blackout (8.6 BLK) 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.

8.6 Blackout reference

Maximum average pressure (MAP)62,000 psi
Nominal case capacity51.0 gr H₂O
Groove / bullet diameter0.338 in (8.59 mm)

Example simulation illustrative

Bullet
Sierra 338 Caliber (.338) 300 gr HPBT MatchKing
Powder
Hodgdon CFE BLK
Charge
16 gr
Barrel
12 in

Muzzle velocity

1,072 fps

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

17,712 – 20,047 – 22,236 psi

nominal is 32% MAP (62,000 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 8.6 Blackout powders

Powders and bullets handloaders commonly use for the 8.6 Blackout, 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 8.6 Blackout bullets

Use MyLoads as a 8.6 Blackout 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 8.6 Blackout in the MyLoads calculator →

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