It may not seem like the same thing to you, but actually it is. The meaning of the 2nd Amendment is clear from reading not only the Constitution, but numerous other writings that elaborate upon the intent. The fact that some people deliberately choose to ignore this is irrelevant, and doesn't make the ordinances any less unconstitutional than the old Jim Crow laws.
"The Second Amendment declares that it shall not be infringed, but this, as has been seen, means no more than that it shall not be infringed by Congress." -- US Supreme Court, U.S. v. Cruikshank, 92 U.S. 542 (1875), Presser v. State of Illinois, 116 U.S. 252 (1886)