No semi-autos at all.

Semi-autoshotguns only when used for small game, fur bearer, turkey or unprotected birds.
(didn't find a rider saying whether or not they were legal for deer, so I would have to say assume no. though you can write or email the PA Game Commission to check.)

Flintlock-only during the main/regular season which is just after Christmass. During the early season you can use any muzzleloader, flint, percussion or inline, that fits in the minimum/maximum regs for the season.