Pretty much, though blanks aren't actually bullets, they're rounds or cartridges. The main difference between blanks and regular rounds/cartridges is that blanks don't have bullets (the metal bit which gets shot out of the gun)
They still have the gunpowder though, so like [email protected] said, they are still dangerous due to the explosion that no longer has to propel a bullet.
That's my best guess. I've shot a gun, but I've never shot a lion, so I'm no expert. I don't even know how to reload one.