The gun Vincent uses is a 1911A1 Auto Ordnance .45 ACP pistol that has been chromed and given pearl grips. Jules' gun is a Star Model B 9mm pistol that has been chromed and given pearl grips, too.
"Butch (Bruce Willis) taunts Zed (Peter Greene) with the samurai sword and says, "You want that gun, don't you Zed? Go ahead and pick it up. I want you to pick it up." This is also said by Sheriff Chance (John Wayne) in Rio Bravo (1959)"
Ha! I knew that line sounded familiar!