This easy to assemble key chain kit features a real once fired 308 (7.62 x 51mm) brass cartridge case and a real 308 bullet.
You will receive a deprimed, once fired piece of 308 brass, which has a a heavy duty clevis pin inside the 308 case. The shoulder of the clevis pin is large enough that it will not fall out of the neck of the case and the shaft of the clevis pin fits right through the slightly enlarged flash hole and the primer pocket. You will also receive a pulled 308 bullet and a chrome key ring.
The clevis pin MUST be installed before pressing the bullet into place. Please take care in pressing the bullet into the case. The bullet needs to be kept aligned with the case. You can also want to use a small amount of epoxy in the case neck before pressing the bullet in to help keep the bullet in place.
For the fired look, just glue and press the bullet into the neck of the case and slide the key ring through the hole in the clevis pin. You should be able to knock these out in about a minute.
For a slightly more polished look, the ding can't be removed so it isn't "new", turn a wooden dowel/jam chuck that fits into the neck of the 308 case. Put the case on that chuck and using Flitz or some other metal polish, polish the case to your desired level of finish.
Or go crazy and try turning your own "bullet" from a piece of acrylic for a one of a kind look.