The pistol-bullet is indeed a civil war era Colt Revolver bullet. The other one you asked about appears to be a Confederate-made 2-groove minie for the Mississippi Rifle. However, the MR minie typically measures approximately .530 in diameter. The 2-groove minie in your photo looks like the same diameter as the yankee 3-groove minie next to it. Is the yankee minie a .54-caliber, or a .58-caliber? Please use a digital Caliber to measure the diameter of both of your minies, in hundredths-of-an-inch, and tell us the result. I'm asking because 2-groove CS Mississippi Rifle minies were only manufactured in .54-caliber size, so if yours is larger than that, it isn't a Mississippi Rifle minie.
