Here is the law, not opinion.
Under federal law, it is as incorrect to say a felon can not own any firearm, as it is to say a felon can own any firearm.
State and federal law do not trump each other. You can be prosecuted in state or federal court.
You are correct that under Texas law, a felon can not posses a firearm until 5 years have passed from the COMPLETION of the punishment.
Under federal law anyone convicted of a crime with a possible punishment being a year or more in jail (ie. felon) , it is illegal "to ship or transport in interstate or foreign commerce, or possess in or affecting commerce, any firearm or ammunition; or to receive any firearm or ammunition which has been shipped or transported in interstate or foreign commerce. "
US Code Title 18 Section 922 (g)
Notice that is states " possess in or affecting commerce, any firearm or ammunition; or to receive any firearm or ammunition which has been shipped or transported in interstate or foreign commerce". So if a firearm has never been shipped into or out of the state (made in Texas), it is not against federal law for a felon to posses it. Bond Arms is made in Texas.
Also look at what a "firearm" is. Under federal law (also Texas law), an antique firearm is excluded in the definition of a firearm.
An antique firearm is:
(A) any firearm (including any firearm with a matchlock, flintlock, percussion cap, or similar type of ignition system) manufactured in or before 1898; or
(B) any replica of any firearm described in subparagraph (A) if such replica—
(i) is not designed or redesigned for using rimfire or conventional centerfire fixed ammunition, or
(ii) uses rimfire or conventional centerfire fixed ammunition which is no longer manufactured in the United States and which is not readily available in the ordinary channels of commercial trade; or
(C) any muzzle loading rifle, muzzle loading shotgun, or muzzle loading pistol, which is designed to use black powder, or a black powder substitute, and which cannot use fixed ammunition. For purposes of this subparagraph, the term “antique firearm” shall not include any weapon which incorporates a firearm frame or receiver, any firearm which is converted into a muzzle loading weapon, or any muzzle loading weapon which can be readily converted to fire fixed ammunition by replacing the barrel, bolt, breechblock, or any combination thereof.
So you can own any firearm made before 1899. Or any replica of a firearm made before 1899 as long as it does not use center or rime fire ammo. A Walker colt is an antique firearm.