According to PC §46.035:
So even without a sign, carrying in a 51% location is illegal.(b) A license holder commits an offense if the license holder intentionally, knowingly, or recklessly carries a handgun under the authority of Subchapter H, Chapter 411, Government Code, regardless of whether the handgun is concealed or carried in a shoulder or belt holster, on or about the license holder’s person:
(1) on the premises of a business that has a permit or license issued under Chapter 25, 28, 32, 69, or 74, Alcoholic Beverage Code, if the business derives 51 percent or more of its income from the sale or service of alcoholic beverages for on-premises consumption, as determined by the Texas Alcoholic Beverage Commission under Section 104.06, Alcoholic Beverage Code;