The "DEFCAD MEGA PACK," a collection of restricted and unrestricted 3D printer plans originally put together by Defense Distributed is now up to version 4.4 and includes several firearms not original to the Wiki Weapon project.
Some of the additions are small, including new barrels for the Liberator pistol in an assortment of other calibers including .25 ACP, .44 Special, .45 ACP and 9x18mm Makarov. The original Liberator barrel chambers .380 ACP and can withstand maybe 10 shots before failing.
The barrel just pops off for reloading or replacement, so it's quite simple to change calibers to work with whatever ammo is on hand.
Some of the other designs are more radical, like the Liberator pepperbox. Also chambered for .380 ACP, this pistol features a four-barreled cylinder that promises increased durability over the original Liberator design and quadruple the capacity.