The part 'shall not be infringed' is not the big issue.
The big issue, which was addressed in Heller and McDonald in 2008 and 2010 was; is the right to have a militia; to be in the militia; or, to have guns for your own personal protection.
It is clear that reasonable regulation does not 'infringe' the right.
I don't even know if there have ever been any cases that defined 'infringe', as regards guns, or gun rights. All the cases are on copyrights.