Three tools on one page: sectional density and form factor from a published BC; a BC measured from your own two chronograph velocities; and a G1↔G7 conversion done the honest way — by matching the 1,000-yard drop of a full trajectory run, labeled an estimate.
1 · Sectional density & form factor
2 · BC from two velocities (your chronograph)
3 · Convert G1 ↔ G7 (trajectory matching)
Read this before you rely on any number here. Predictions use the standard G1/G7 drag models and the data you enter — they are estimates, not measurements, and they are never load advice. Confirm with live fire at distance. For anything you load yourself, work only from current published manuals (Hodgdon, Sierra, Hornady, Lyman), start low, and work up. TruingLog publishes no load recipes and suggests no charge weights.