Bullet ID assistance - Lattice bodied bullet

The bullet pictured was recently found by a during an archaeological metal detection investigation. The bullet is about .55-caliber and weighs 15 grams (231 grains). We would be grateful for any identification assistance. Is it a shotgun slug or something else? LIBI

It looks like a typical wadcutter projectile and given the approximate diameter it seems to have been a .38 Spc. or .357 Mag…

That makes sense. The site has later goose and wild fowl ammunition components on it but was also a picket area during the Civil War.

At 231 grains, considerably more than the weight of the.38/.357, 148 grain Hollow Base Wadcutter, or 158 grain Semi-Wadcutter.
My guess would be a .45 calliber, perhaps a handload for a Bullseye shooter. 230 grains is standard for the .45 ACP, and I have loaded the same type bullet in a .45 Colt for a small game hunting round.