Documentation
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LoadOut solves the whole flight of the bullet every time an input changes. Nothing is a lookup table, nothing is interpolated from a chart, and nothing is assumed: an input the solver needs and does not have stops the solution and is named on screen.
The solver
Inputs
Inputs come in three groups. The first two have no defaults beyond the four disclosed starting values below; a blank field stops the solution and is named on the "Can't compute firing solution yet" card. Environment fields fall back to the standard atmosphere, and the solution says so.
| Input | Group | Unit | If blank |
|---|---|---|---|
| Bullet Weight | Projectile | gr / g | No solution; named on the card |
| Bullet Diameter | Projectile | in / mm | No solution; named on the card |
| Ballistic Coefficient, with its drag model | Projectile | — | No solution; a catalog coefficient LoadOut could not source is withdrawn rather than used, and the card says why |
| Bullet Length | Projectile | in / mm | Spin drift is left out, and the solution says "Spin drift not included. Add this bullet's length (OAL) to compute it." |
| Muzzle Velocity | Muzzle | fps / m/s | No solution; named on the card |
| Zero Range | Muzzle | yd / m | Starts at 100 yd on a new firearm, disclosed as a starting default |
| Sight Height | Muzzle | in / mm | Starts at 2.0 in on a new firearm, disclosed as a starting default |
| Temperature | Environment | °F / °C | 59 °F, the standard atmosphere, disclosed |
| Station Pressure | Environment | inHg / hPa | 29.92 inHg, the standard atmosphere, disclosed |
| Humidity | Environment | % | The standard atmosphere, disclosed |
| Station Altitude | Environment | ft / m | Sea level, the standard atmosphere, disclosed |
| Wind speed and direction | Environment | mph / km/h | No wind. The solver never invents a breeze |
| Twist Rate | Advanced | 1:in | Spin drift and the stability check are left out and labelled |
| Twist Direction | Advanced | Right / Left | Starts at Right, disclosed as a starting default until you set it |
| Incline | Advanced | ° | Level |
| Powder Temperature Sensitivity and Reference Temperature | Advanced | fps per °F / °C | No temperature correction to muzzle velocity |
| Latitude and Firing Azimuth | Advanced | ° | The Coriolis correction is left out and labelled |
| Zero Temperature, Zero Station Pressure, Zero Humidity | Zero conditions | as above | The zero is assumed to have been shot in the current conditions |
The standard atmosphere
When every environment field is blank, the solver uses the ICAO standard atmosphere: 59 °F, 29.92 inHg of station pressure, dry air, at sea level. Every surface that shows a solution then says "Using ICAO standard atmosphere" for as long as that is true: the Ballistics tab, the Target Card, Range Day, the Hit Probability Map, True DOPE, Full Analytics, the exported DOPE table, and Match Day. Density altitude is never typed; LoadOut works it out from the four environment values and shows it beside them.
Drag models
| Model | Reference shape | Use it for |
|---|---|---|
| G1 | Flat-base, the classic Ingalls standard | Most published coefficients; flat-base and short-boat-tail bullets |
| G2 | Aberdeen J projectile | Rarely published; some military profiles |
| G5 | Short boat-tail | Short boat-tail bullets |
| G6 | Long flat-base | Long flat-base bullets |
| G7 | Long boat-tail, very-low-drag | Modern match and long-range bullets; the coefficient most makers publish beside G1 |
| G8 | Very long flat-base | Long flat-base bullets |
| Measured curve | The bullet itself | 295 bullets ship with a measured drag-coefficient-versus-Mach curve, applied automatically when you pick one; it replaces the table and the coefficient |
A coefficient is only meaningful with its model: the same bullet's G7 value is roughly half its G1 value. LoadOut stores the two together and never mixes them.
Effects
Spin drift and Coriolis can be switched off under Settings › Ballistics & Range Day. When either is off, every place it would have appeared says so rather than silently showing a smaller number.
Truing
True DOPE fits the solver to what your rifle actually did, and it is free. Three methods, each correcting a different thing:
| Method | What it corrects | When to use it |
|---|---|---|
| Muzzle Velocity | The speed the bullet left with | Your drop is off by the same proportion everywhere, or you have no chronograph |
| Drag Scale | One factor across the whole drag curve | Drop is right up close and drifts with distance |
| DSF Table | A drag factor per Mach band instead of one number | Long-range work where a single factor cannot fit both the supersonic and transonic regions |
Each can be cleared separately: Clear Muzzle Velocity, Clear Drag Scale, Clear DSF Table. Recording a factory box's published velocity on a profile clears any truing you had fitted, because a published velocity comes off the maker's test barrel, and your rifle is not that barrel.
Confidence flags
The solver reports how much it trusts each row, and the words are the app's own:
The flags are per bullet, never a fixed distance: a .308 match load goes transonic near 1,000 yd, a high-coefficient magnum stays supersonic past 2,500. A measured drag curve relaxes the transonic flag, because the curve was measured through that band.
Limits
Outputs
| Output | Where | What it holds |
|---|---|---|
| Solution | Ballistics › Solution; Range Day; the watch | Elevation and windage to dial or hold at one distance, with the confidence flag and the environment source |
| DOPE table | Ballistics › DOPE; the watch; export | Every distance in your ladder, with drop, wind, velocity, energy, and time of flight |
| Target Card | Ballistics › Target Card; Range Day; the watch | A plan across a string of targets, with the turret carried between them |
| Reticle holds | Ballistics › Reticle; the scope view | The same holds drawn on your reticle |
| Analytics | Ballistics › Analytics; Full Analytics (Pro) | Transonic and subsonic distance, maximum point-blank range for an 8-inch vital zone, the energy threshold, maximum ordinate, time of flight, spin drift, Coriolis, and the velocity and energy curves |
| Hit probability | Hit Probability Map (Pro) | The probability of a hit at any distance from your group size, range uncertainty, and wind uncertainty |
The Internal Ballistics Estimator
A separate, Pro tool under Tools & Resources that estimates muzzle velocity and peak chamber pressure for a hypothetical load from case capacity, the powder's relative quickness, charge weight, bullet weight, diameter, and overall length, and barrel length. It is a mobile estimator, not a pressure-testing instrument, and the app says so on every visit with a banner that cannot be dismissed:
Always verify against a published manual. The predicted peak pressure tends to read LOW. Treat it as a floor, not headroom; your actual peak is likely higher. Never add powder or exceed a published max because a prediction sits below it.
Across its test corpus the estimate lands within about 10 percent on velocity and 15 percent on pressure. It applies cleanly between 10 and 110 percent loading density, and it warns on the cases that push it outside its calibrated band: a dual-category magnum-pistol powder, a low loading density, and a very slow powder, each with its own advisory. An unknown powder returns nothing rather than a substitute.