TexasCHLforum.com

I think a key factor in this doctrine is what constitutes "official purposes."

It's perfectly legal for anyone to mail rifles and shotguns, and for FFL holders to mail handguns, so, pretty obviously, it simply must be legal to carry such into the Post Office.

Given that, another interesting question is whether self-defense is such a recognized "official purpose?"

By the way, reading the other thread linked above, the issue of whether the USPS is a governmental entity is interesting.

If it is an agency of the federal government, then it seems to me that the conflict with the Texas law according to the posted CFR must rule, and it's legal because Texas law says so.

If they want to claim that the USPS is not a governmental entity, then they must have signage which complies with 30.06.

It must be one way or the other.