Carbon steel
The Bauer Automatic is an approximate copy of the Baby Browning and was designed as such in order to avoid copyright infringement claims from FN, which at that time still had USA patent protection on various components of the 1931 Baby Browning. For example, the Bauer Automatic was produced using 416 stainless steel investment castings while the FN Baby Browning slide and frame were originally produced from 8620 carbon steel bar stock. (However, with the purchase of a European-based investment casting operation during the early 1970s, the FN pistol frame and slide were produced from 8620 Carbon steel investment castings). The Bauer Automatic utilized a different auto safety spring and the barrel was removed (and the slide released from the frame) by twisting it clockwise 45 degrees, rather than counterclockwise, as is the case with the FN Baby Browning. The Bauer Automatic has engraving on both sides of the slide, whereas the FN Baby Browning has engraving only on the side opposite the ejection port. This copy of the Baby Browning is not known for its consistent machining tolerances. Many parts interchange with the FN Baby Browning, including grips, magazines, and various internal parts.