How to Build a DOPE Card
Woody's answers are based on published federal and state law. Not legal advice. Consult a licensed attorney for your specific situation.
A DOPE card records your rifle's bullet drop and wind drift corrections at various distances. Log actual shooting data including distance, elevation clicks, windage adjustments, and environmental conditions.
How This Affects Your Precision
DOPE (Data On Previous Engagements) cards eliminate guesswork by providing proven firing solutions from your actual range sessions. They account for your specific rifle, ammunition, and shooting style rather than theoretical ballistics. Building accurate DOPE requires consistent range time and meticulous record keeping.
The Detail
Start with a basic template that includes columns for distance, elevation adjustment in MOA or mils, windage correction, wind speed and direction, temperature, and barometric pressure. Many shooters add fields for ammunition lot numbers since different lots can shoot to different points of impact. Your DOPE card should reflect actual fired rounds, not ballistic calculator predictions.
Begin data collection at your rifle's zero distance, typically 100 or 200 yards, then work outward in logical increments. Record the exact number of clicks or holdovers needed to center your groups at each distance. Pay attention to environmental conditions since temperature and altitude significantly affect bullet trajectory. Cold weather typically requires less elevation adjustment while hot conditions need more.
Document wind calls carefully since this separates good shooters from great ones. Note the wind speed, direction relative to your firing line, and the corrections that actually worked. Full value winds require maximum correction while quartering winds need about 70% of the full value adjustment. Record mirage conditions and their relationship to actual wind effects downrange.
Transfer proven data to a waterproof card or laminated sheet you can reference quickly. Organize the information logically with the most commonly used distances prominently displayed. Some shooters prefer separate cards for different ammunition types or seasonal conditions. Update your DOPE regularly as your shooting skills develop and equipment changes.
Build Impact
Your DOPE card becomes more valuable than any ballistic app because it reflects real performance from your specific setup. Consider environmental extremes you'll encounter when designing your data collection plan since temperature swings of 40 degrees can shift impact by several MOA at long range.