A screw will be placed in McCargo's foot to help the fracture heal faster.
McCargo, the second of Buffalo's two first-round draft picks, was hurt late in the fourth quarter of Sunday's game.
The Bills traded up on draft day to grab the North Carolina State product, who manned a collegiate defensive line that included fellow draftees Mario Williams and Manny Lawson.
McCargo has six tackles in five games this season. He had two tackles on Sunday.
Exploding whale video goes viral on Internet
Couple mistakenly served bag of cash at McDonald's drive-thru