Abstract: A firearm, such as a pistol, capable of accepting into its' magazine well either a narrow body (single cartridge row) or a wide body (double cartridge row) magazine is disclosed. The magazine well within the pistol's grip is bevelled to receive a bevelled wide body magazine. The magazine well has at least three contact points for contacting, aligning, and securely positioning a narrow body magazine within the grip. A firearm embodying the present invention can be a .45 ACP, semiautomatic, 1911 government model style pistol.