The HS 129 B-2 had the automatic 37mm or 75mm cannon. As the war progressed, the 75mm became more common. They both fired AP ammunition.
The B-1 version had 4/7.9mm MG's and either dual 20mm or a single 30mm with the 30mm being loaded with AP rounds. The B-1 version also carried 8/50kg bombs.
BTW... I have multiple sources that list the max speed of the Hs-129 as 253mph at around 12k *unloaded*. It would be near Il-2 speeds once loaded for combat.