A ballistic coefficient describes a projectile relative to a named reference drag model. FreeDOPE therefore needs the model and coefficient as one paired input.
Start with the source
Find the projectile or ammunition record that supplied the coefficient. Record whether it labels the value G1 or G7.
Choose the same model
Select G1 for a G1 value or G7 for a G7 value. Do not choose the model by projectile appearance while keeping a coefficient published for the other model.
Enter the matching coefficient
Copy the coefficient with its original precision and keep enough source identity in the profile name or notes to find it again.
Verify the resulting curve
Recalculate and compare known distances. A model mismatch often becomes more visible as distance and flight time increase.
Expected result
The profile preserves a coefficient, drag model, and source that another reviewer can identify and compare with observed data.