The Northwest Territorial Mint offers Silver Bullion in 1 ounce .45 ACP "bullets." These bullets aren't actually live ammunition, but are investment-grade .999-fine silver. Larger calibers such as .50 BMG available as well. Be sure to watch the interesting video at the link on the making of the bullets.
Note: This post is not meant to be an investment recommendation, nor am I in any way affiliated with the seller. I just find this to be an interesting object of desire.
HT to zercool.