I would say .44 cal semi wadcutter.Looks modern-ish. Bigger than .44 S&W or.44 magnum bullet diameter.
Ya, that was my first inclination too, but the diameter isn't right for most .44 calibers. Most come in Diameter: .429 to .430 inches, which would be a bit less than the .440 on the micrometer image. I suppose if the micrometer wasnt zeroed out prior to measurement it could read larger. The weight is 200.6 grains which is certainly in the realm of .44 S&W, magnum, etc..I would say .44 cal semi wadcutter.
Looks like a black powder bulletWeighs 13 Grams
It’s solid with a flat tip.. 3 rings
Please also see my other post about identifying 2 different bullets
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