Yes the bullet is non-jacketed lead alloy (not pure lead.) The alloy is composed of 92% lead, 6% antimony & 2% tin with a Brinell Hardness Number of 18.
In 45acp the round doesn't get hot enough to worry about barrel leading. But to be safe I usually recommend shooting a few FMJs after every 200 rounds fired or so. But if you clean your gun regularly this is a non-issue.