30-40 krag multi ball

Can someone shed some light on the worth of a single cartridge in good shape? I have around 8 in my collection and wondering

Also, dealing with the krag cases, I have a slew of shotshells style in various lengths that I would like to ask the same as well.

The price for the 30-40 Krag multi ball is worth what some one will pay for it. I have seen the asking price in the $20-30 range but that may be influenced by specific headstamp.I paid about $8 for the one I have.