MyLoads Open the calculator →

6mm GT Load Data & Ballistics Calculator

Estimate chamber pressure and muzzle velocity for the 6mm GT 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.

6mm GT reference

Maximum average pressure (MAP)62,000 psi
Nominal case capacity42.0 gr H₂O
Groove / bullet diameter0.243 in (6.17 mm)

Example simulation illustrative

Bullet
Sierra 6mm 243 Caliber (.243) 100 gr SBT GameKing
Powder
Hodgdon Superformance
Charge
37.6 gr
Barrel
24 in

Muzzle velocity

2,846 fps

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

32,161 – 44,956 – 60,624 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 6mm GT 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 6mm GT in the MyLoads calculator →

More cartridges