Plenum: Airgun Tuning Log

Plenum is a tuning instrument for PCP airguns. Connect an FX chronograph, shoot a string, and see where your regulator holds, where it lets go, and where more hammer stops paying for itself.

FIND THE PLATEAU
Shots land on the chart as you fire. Plenum marks the regulated plateau and the shot where the fill falls off the reg, so your usable shots per fill are counted, not guessed. Average, SD and ES update with every shot.

FIND THE KNEE
Step hammer or regulator one setting at a time. Plenum finds the point where velocity flattens and shows what each step past it costs. A sweep that never flattens says so instead of inventing a knee.

NOTHING TO TYPE
Works with the FX Pocket Pro, Pocket V2, Pocket D1 and True Ballistic over Bluetooth. Every velocity arrives on its own.

EVERY TUNE KEPT
Unlimited airguns. Every string and sweep is saved, with your best tune on top of the rack. Excluding a bad read hides it from the statistics and never deletes it.

PELLETS AND SLUGS
A searchable catalogue of 156 airguns and 331 pellets and slugs, with weights, calibres and ballistic coefficients. Add your own when yours is missing.

WHICH PELLET IS REALLY TIGHTER
Spread is shown with its 95% interval, so a lucky string never passes for a better pellet.

RANGE CARDS
Send a saved string's velocity and spread to FieldSolve for a ballistic solution.

BUILT FOR THE BENCH
Dark for indoors, light for a sunlit range. Every figure is set in fixed-width digits that don't jump while they change. Bar or psi, fps or m/s, grains or grams, ft·lb or joules. In English, Finnish, Swedish, German, French, Spanish, Italian, Czech and Polish.

YOUR DATA
Everything is stored on your phone, and no account is needed. Sign in with Google to back your strings up and add them to a shared record of how pellets really perform. Turn that off in Profile at any time, or delete your account there.

FREE
No subscription, no ads, nothing locked.