Field solver · 6DOF, spin drift, Coriolis
Type the distances you are shooting. Tap a row to put it in the readout above.
Tap a rifle to shoot it; its bullet, sight and zero are edited inside. A rifle keeps the bullet, muzzle velocity, twist, sight height, zero, reticle and turret — not the weather or the distances, which change every outing. Edits are not written back until you choose Update from its ⋯ menu, so a rifle you have changed says “modified” until then.
A rifle preset saves the barrel and zero, the bullet and the sight as they stand right now, in one entry, and loading it replaces all three — a rifle comes with the load it shoots and the scope bolted to it. To move just one of them, use the Bullet or Sight preset inside the rifle. Presets travel between browsers; the cards above stay in this one.
Saved presets go to a public list.
Presets you save are sent to a list everyone using this page can see and load, and anyone can add to it. Do not put anything in a preset name you would not publish. You can delete the ones this browser saved; you cannot delete other people's.
Your zero was set on one particular day. Turn this on and the scope angle is solved under those conditions while the bullet flies through today's air — which is what actually happens. Leave it off and the solver assumes you zeroed in the conditions you are shooting in now.
The BC must match the standard: a G1 number entered against G7 will be wrong by roughly a factor of two.
Both of these leave the device. “Use my location” asks the browser for your coordinates; “Fetch live weather” sends those coordinates to the Open-Meteo public API and fills in temperature, pressure, humidity and wind. Nothing else on this page ever contacts the network, and neither runs unless you press it.
Station pressure is what a Kestrel reads — not the altimeter setting corrected to sea level. Positive shot angle is uphill. Latitude and azimuth drive the Coriolis term.
Drag the dial, or use the arrow keys. The clock is relative to your shot: 12 o'clock blows from the target into your face, 3 o'clock from your right.
A turret factor other than 1.000 scales the clicks you dial. Set it only if you have measured your scope's tracking on a tall target: a scope that moves 9.7 MIL when you dial 10.0 has a factor of 10.0 / 9.7 = 1.031.
Every logged shot stores the prediction, what you actually dialled, where it landed, and the complete setup that produced it — bullet, rifle, zero, atmosphere and wind. It is recorded to check whether the model is realistic; it never feeds back into the solver, because a prediction corrected by the last observation is no longer an independent test of anything.
Pre-filled with what the app told you. Change it only if you dialled something else.
This is the single most useful number for checking the model. Leave it blank if you did not measure it.