Jenrick, under federal law that isn't a firearm, either.
Per the the ATF:
the term “firearm” is defined in the Gun Control Act of 1968, 18 U.S.C. Section 921(a)(3), to include (A) any weapon (including a starter gun), which will, or is designed to or may readily be converted to expel a projectile by the action of an explosive; (B) the frame or receiver of any such weapon
A black powder pistol definitely falls under this definition. Now the AFT has been VERY reluctant to file charges on this in my experience, and the rule of thumb I have received from them is that the item in question must use fixed case ammunition that is commercially available. We had a suspect in possession of an actual Colt SAA in .45LC (not a replica) along with a bunch of narcotics, and when we went for the federal firearms enhancement we were told that they would not file charges as .45 LC was not "generally commercially available." YMMV however.
However, it would still be a deadly weapon if used in that way. Meaning, if you shot someone with one, you'd still be charged with ADW. The court wouldn't say "oh but that's not a firearm so it's ok."
Of course, in Texas it certainly qualifies as a deadly weapon, which would lead to enhancement on a lot of different charges.
How does that fit with TX law? Are only modern handguns prohibited from open carry, or other weapons as well?
Basically, if you read Chp 46.01.05: ""Handgun" means any firearm that is designed, made, or adapted to be fired with one hand" . 46.01.03: "Firearm" means any device designed, made, or adapted to expel a projectile through a barrel by using the energy generated by an explosion or burning substance or any device readily convertible to that use. Firearm does not include a firearm that may have, as an integral part, a folding knife blade or other characteristics of weapons made illegal by this chapter and that is:
(A) an antique or curio firearm manufactured before 1899; or
(B) a replica of an antique or curio firearm manufactured before 1899, but only if the replica does not use rim fire or center fire ammunition.
So as we've discussed already a cap and ball black powder replica pistol does not meet the definition of a firearm or a handgun.
Sec. 46.02. UNLAWFUL CARRYING WEAPONS. (a) A person commits an offense if the person intentionally, knowingly, or recklessly carries on or about his or her person a handgun ....
In short you can open carry a black powder pistol, as it's NOT a "handgun" under Texas law. You can open carry a "Firearm" which is NOT a "handgun" so long as you don't do it anywhere the law says you can't. Hence you can legally walk down S. Congress Ave. in front of the capital with a AK/AR/Shotgun/Etc. under this section, while doing so with a holstered unconcealed Raven .22LR is illegal.
Now there is a seperate offense under Sec. 42.01. DISORDERLY CONDUCT. (a) A person commits an offense if he intentionally or knowingly: ... (8) displays a firearm or other deadly weapon in a public place in a manner calculated to alarm
We deal with this on a regular basis when folks are open carrying to protest or just for the heck of it. Common sense and good judgement are the rule of the day on what constitutes a "manner calculated to alarm." If you show up at an anti-gun rally with your AR and are wandering around in low ready with the firearm, IMO you're probably there to cause alarm to the protestors. If on the other hand you are there with a bunch of Pro 2A ralliers, you aren't there to cause alarm regardless of the fact that someone might be alarmed.
-Jenrick