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Load tuning

Load comparison tool

Quickly contrast two loads with calculated muzzle energy, power factor, recoil estimates, and percent differences.

Give each load a short label.

Projectile mass for Load A in grains, not total cartridge weight.
Projectile mass for Load B in grains, not total cartridge weight.
Chronograph velocity for Load A in feet per second. Compare readings captured at the same distance and under similar conditions.
Chronograph velocity for Load B in feet per second. Compare readings captured at the same distance and under similar conditions.
Powder mass in Load A. It is used only for the free-recoil estimate and must not be treated as load-data guidance.

Used for recoil estimation.

Powder mass in Load B. It is used only for the free-recoil estimate and must not be treated as load-data guidance.
Ready-to-fire firearm weight in pounds, including the optic and accessories. Both loads use this same weight for comparison.

Used for recoil calculations. Enter the weight for your platform.

Optional reference value shown in the summary. It does not alter energy, power factor, or recoil because measured velocity already reflects your barrel.

Optional context only—used in summary text.

Select the SAAMI propellant-gas velocity relationship that best matches the firearm. It changes only the free-recoil estimate.
Energy A —
Energy B —
Power factor gapLoad B power factor minus Load A power factor. Power factor is bullet weight in grains multiplied by velocity in fps, divided by 1,000. —
Recoil differenceEstimated free-recoil energy for Load B minus Load A. This does not predict perceived recoil or firearm operation. —