Quoted:
You can drive around with a loaded M16 hanging in the gun rack of your pick up if you wanted. Properly NFA registered of course.
It is legal but you could be arrested for it. Texas law in regards to NFA items has a major flaw.
Sec. 46.05. PROHIBITED
WEAPONS.
(a) A person commits an offense if he intentionally or
knowingly possesses, manufactures, transports, repairs, or sells:
(1) an explosive weapon;
(2) a machine gun;
(3) a short-barrel firearm;
(4) a firearm silencer;
(5) a switchblade knife;
(6) knuckles;
(7) armor-piercing ammunition;
(8) a chemical dispensing
device; or
(9) a zip
gun.
(b) It is a defense
to prosecution under this section that the actor's conduct was
incidental to the performance of official duty by the armed forces or
national guard, a governmental law enforcement agency, or a correctional
facility.
(c) It is a
defense to prosecution under this section that the actor's possession
was pursuant to registration pursuant to the National Firearms Act, as
amended.