Old bullet with rings..how old?

[qaela4]

Found this at a park that has been around since at least mid 1850's, used as a mustering grounds and a fair grounds. Any help by those "in the know" would be great. I was told the one on the right is a .25 and the one on the left could be as well or a .32. I know nothing and ignorance can only be cured with knowledge so please educate me if you can. Thanks in advance to all who try.

 

[BosnMate]

Need measurements in 1/1000 of an inch for positive ID.

 

[Ninjafossils]

Well the one on the right is definitely a colt .45 pistol bullet. The one on the left looks like a post war bullet. It might be civil war, but we do need better measurements and pictures.

 

[l.cutler]

Looks too small to be a .45 but like BosnMate said, measurement will give you the caliber.

 

[jwarner51]

The right one doesn't have a jacket on it does it. Kinda looks like it from the bottom, just covered with corrosion.

 

[BosnMate]

A friend of mine had one of those little .25 auto's years ago, and as I recollect the gun fired full metal jacketed bullets, probably to prevent feeding problems would be my guess. Stand the bullet up on a ruler, if it's about 1/4 inch it's probably .25 caliber, and if it's almost 1/2 inch it's probably .45. The one on the left in the picture, which only shows one view, which limits positive ID as much as not having proper measurements. In the view you show it looks like a target bullet, or as they are called, "wad cutter." Those bullets are flat across the end so they will cut a crisp, clean hole in a paper target. However it has been fired, and depending on what it hit, it might have been flattened by impact. At first glance it looks like a .45 ACP and a .38 wad cutter, a dime measures 3/4 of an inch, so size comparison looks to me to be smaller than .45, but without measurements we are just guessing.

 

[qaela4]

 

[BosnMate]

It looks like your full metal jacket bullet is about 5/16 inch, which is .3125. A .38 bullet is .357-.358, which is also the size of a 9mm, however, .312 is the size of a .32 caliber bullet.
Your find was probably fired from a .32 caliber semi auto, which feeds the metal jacket more reliably than a soft lead bullet. The first bullet on the left looks like it's 9/32, which is .281, which is about
6mm, .283 = 6.5mm, which was the Japanese WWII cartridge, as well as several European firearms. The third bullet on the right is about 5/16 which again is about .30, which makes me
think it's a 30 Caliber rifle bullet, perhaps military 30-06. All of this is an educated guess, or a swag, (scientific wild assed guess). If you want positive ID, you need positive measurements
in 1/1000 of an inch.