The right of the citizens to bear arms in defence of themselves and the State shall not be questioned. (Art. 1, §21)
§6120. Limitation on the Regulation of Firearms and Ammunition.
(a) General rule. No county, municipality or township may in any manner regulate the lawful ownership, possession, transfer or transportation of firearms, ammunition or ammunition components when carried or transported for purposes not prohibited by the laws of this commonwealth.
Philly is a hard case, but there is a good consistent effort to overturn Philly's strict (unconstitutional) gun control.