DOPE Ballistic — Calculator

DOPE is an RK4 ballistic calculator with G1/G7 drag models, velocity-banded BC, and custom drag curves. It includes group analysis, a shooting session logbook, stage cards for PRS matches with clock and tally, analytical insights, and tools like a range finder, moving target lead, MPBR, WEZ, and converters. It offers truing at no cost — MV, BC/CDF, and DSF from observed drop/velocity. FEATURES: 1. Ballistic solver - Full point-mass trajectory (RK4) with gravity, drag and slope - G1 and G7 drag models - BC bands by velocity - Custom drag curves — Cd/Mach data (ie: Lapua Doppler) - Come-up/hold in MRAD, MOA, cm and scope clicks, with direction labels - Shot info: retained velocity, energy, time of flight and Mach at target — transonic/subsonic warning below ~Mach 1.2 - Full range/drop table with toggleable columns - Interactive trajectory graph — drop/ToF, correction, velocity/energy panels - Load comparison overlay - Precision factors (opt-in): MV temp correction, MV-SD dispersion, spin drift, aerodynamic jump, Coriolis/Eötvös, windage zeroing, per-cartridge zero offset - Runs in-browser and fully offline 2. Equipment management - Multiple rifles - Multiple cartridges/loads - Reload recipe reference - Bundled bullet library with published BCs - Holdover reticle view — import and default - Chronograph sessions data entry and import (Garmin, Athlon, LabRadar) - Barrel-life tracker - Cleaning log per rifle 3. Weather & shot inputs - Automatic weather fetching - Range-bracketed (zoned) wind - Standard atmosphere (ISA) - Coriolis (optional) 4. Zeroing workflow - Atmospheric Zero — adapted to current atmospheric conditions - Truing — MV, BC/CDF (velocity or drop), or DSF - Truing factor display - Scope click calibration — tall-target test turret correction - MV-vs-temperature auto-fit from every logged reading - Ladder test — velocity-vs-charge 5. Groups analysis - Groups precision analysis — calibrated grid, photo overlay, live ES/Mean Radius/CEP/R95 - Cold-bore and excluded shot tagging - Shareable links 6. Shooting logbook - Sessions (DOPE sheet) — date, weather snapshot, hit/miss, corrections - Session summary — hit %, cold-bore result, point-of-impact bias - Selectable scaled targets with shot marker — IPSC silhouettes, rectangles, gongs - Session photo gallery - LR runs — session aggregate 7. Stage cards - Planned distances and wind holds - Auto-filled editable vertical/wind hold - Full-screen card viewer with color-graduated distance levels - Past-run logging per stage - Match type: PRS (par-time + tally), Practice (no timer), or Custom (per-stage / shared overall match clock / no timer; hit-count or points-per-target scoring) - Export — Print/PDF, CSV, PNG - Match — group multiple stage cards into one match 8. Statistics & analysis - Insights — data-driven suggestion cards - Overview - Group accuracy - Precision trend - By-cartridge breakdown - Load comparison - Session hit rate - Cold-bore analysis - Wind accuracy - Call bias - Position & support hit rate - MV trend 9. Field tools - Range estimation - Maximum Point Blank Range (MPBR) - Moving target lead - Hit probability (WEZ) - Printable zeroing target - 3D trajectory 10. Converters - BC from two speeds - MOA ⇄ MRAD at distance - Click value at distance - Slope angle - Cant error - Imperial ⇄ metric unit converter 11. Units, data & app-wide Installable PWA — works fully offline, updates in the background Optional accounts with multi-device cloud sync (offline-first) Full JSON backup — export/import your data Per-quantity metric ⇄ imperial switching; engine always computes in SI Theme — dark / light / system