A free interactive visual explainer of the core ballistic and optical ideas behind every shot. Move the sliders, watch what happens. Universal physics, applicable to bullets, arrows, and shotgun patterns.
Twelve interactive widgets cover trajectory and line of sight, angular vs linear precision, how groups are measured, precision vs accuracy, wind drift, hold vs dial, click value, parallax, first vs second focal plane, MIL ranging, atmospherics (wind, temperature, density altitude), and ballistic coefficient. Each widget uses sliders the user can move directly to see how a single variable changes the outcome.
The page is structured so a beginner can read it end-to-end as a primer or an experienced shooter can jump to a specific concept. No numeric readouts in the discipline-neutral primers; quantitative widgets show real units (MOA, MIL, click values).
A tutorial covers one concept end-to-end at someone else's pace; a wall of text describes ballistics without letting the reader test the relationship. Driving the sliders puts the relationship on screen, including the counter-intuitive cases — true MOA is not 1 inch at 100 yards, a 1 MOA error grows at distance, parallax depends on eye position, a second focal plane reticle subtends differently at different magnifications — so each term ends up attached to a working model rather than to a definition.
For the mental side of shooting, see /focus: a box breathing pacer, a quiet-eye fixation trainer, a pre-shot routine builder with a printable card, and a Stroop attention game used as a pre-load state check.
Live conditions for indexed shooting ranges → range atmospherics directory (Crumlin Sportsmen's Association · Silverdale Gun Club).