ChairGun is where a generation of airgunners learned to read a trajectory. It is also legacy software now — no longer actively updated and awkward to run on a modern phone. PelletArc picks up the same airgun-first thread and brings it to today's iOS and Android: real pellet drag laws, a BC you calibrate from your own drops, and the holdover in one tap.
The two tools share a worldview: solve the airgun problem properly, on its own physics, instead of stretching a rifle calculator over a pellet. ChairGun did that first. PelletArc does it on a phone you already carry — with real airgun drag laws, BC truing from your groups, a sourced pellet catalogue and PDF cards you can take to the firing line.
| What matters to airgunners | PelletArc | ChairGun |
|---|---|---|
| Airgun drag laws (GA, GA2, slug, wadcutter, round ball) | ✓ | ✓ |
| Velocity-dependent BC truing from your observed drops | ✓ | — |
| Sourced pellet catalogue, tagged by data quality | 1,680 | — |
| Answer-first, single-screen solve | ✓ | Form-driven |
| Reticle library | 15 (mil & MOA) | Holdover focus |
| Holdover / turret card PDF export | ✓ | Print-oriented |
| .22LR rimfire (RA4) & rifle (G1/G7) | ✓ | Limited |
| Works fully offline · no account | ✓ | ✓ |
| Actively maintained · modern OS support | ✓ | Legacy |
| Pricing | Pay once | Free / legacy |
Comparison reflects PelletArc's current feature set and ChairGun's well-known, legacy desktop design. ChairGun is independent software associated with Hawke Optics; PelletArc is not affiliated with ChairGun or Hawke.
PelletArc solves a diabolo as a diabolo with real airgun drag laws — GA, GA2, slug, wadcutter and round ball — and its drag-model provenance even includes ChairGun reference data. The inheritance is honest; the app is new.
Log two or three real drops and PelletArc fits a velocity-dependent BC curve to your pellet and barrel. Your DOPE becomes the calibration — the strongest answer to airgun BC scatter, and a step beyond a single typed-in number.
No desktop, no emulator, no fiddling to make old software run. The whole solve is one thumb-friendly screen — readable in the sun, kind to night vision — and the holdover card exports as a PDF you can take outside.
None of this is a teardown. ChairGun taught a generation of airgunners to think in trajectories, holdover and ballistic coefficient — the very vocabulary PelletArc is built around. Some of the drag physics PelletArc carries traces back to ChairGun reference data, and we credit it in the app.
PelletArc keeps ChairGun's airgun-first instinct and adds what a phone era makes possible: nine real drag laws, a 1,680-pellet catalogue tagged by data quality, velocity-dependent BC truing from your own drops, 15 angular-correct reticles and exportable holdover cards — all fully offline, no account, paid once. It is the same destination, reached with today's tools. See the PelletArc vs Strelok comparison for how it sits against the rifle-first option.
One-time purchase, no subscription. See pricing, browse the guides, or read about .22LR ballistics and the physics under the hood.
iOS & Android · one-time purchase · works fully offline.
Launching on iOS & Android. Pay once — no subscription.