Nowhere does the 2nd state what types of arms. The 2nd says the “right of the people” as a separate clause from the militia. Furthermore, in the Federalist Papers and writings of the Founders and Framers “The Militia” is the people, separate from any state or federally organized military body.
The purpose of the 2nd was so The People would be as well armed as, and able to resist a government that slipped into tyranny.
Both Heller and McDonald SCOTUS decisions affirmed the the right to keep and bare arms is an individual right, not a collective right.