TexasCHLforum.com

Solaris wrote:

ScottDLS wrote: If state/local put up the signs it would violate state preemption of firearms laws, so they could not make it a criminal offense.

No it would not violate that, as the law specifically allows it. Google-Fu FTW once again.

Sec. 229.001. FIREARMS; AIR GUNS; KNIVES; EXPLOSIVES. (a) Notwithstanding any other law, including Section 43.002 of this code and Chapter 251, Agriculture Code, a municipality may not adopt regulations relating to:
(1) the transfer, private ownership, keeping, transportation, licensing, or registration of firearms, air guns, knives, ammunition, or firearm or air gun supplies; or
(2) the discharge of a firearm or air gun at a sport shooting range.
(b) Subsection (a) does not affect the authority a municipality has under another law to:
...
(6) regulate the carrying of a firearm or air gun by a person other than a person licensed to carry a handgun under Subchapter H, Chapter 411, Government Code, at a:
(A) public park;

So as I wrote, unless you are one of the exceptions, the sign is enforceable.