Dear Old School Gun Guy On The Internet,
A "blog" is a thing on which there are individual tidbits called "posts". When you post something on your blog (say, for example, a rambling five-paragraph discourse on why damned kids need to get off your lawn) you don't say "I wrote a blog today about why you kids need to get off my lawn." The correct usage would be "I wrote a post today about why you kids need to get off my lawn."
If you wrote a review piece on the Blastomatic 2000 for Guns & Ammo, you wouldn't tell everybody you wrote a magazine, would you? No, you'd tell everyone you wrote an article. Same thing.
To do it the first way makes you sound like Joe Biden and, really, who wants that?