It can be fast, but some Sheriffs don't like having their "power" challenged.
§724.11, WEAPONS
4. The sheriff or commissioner of public safety shall approve or deny an initial or renewal
application submitted under this section within thirty days of receipt of the application. A
person whose application for a permit under this chapter is denied may seek review of the
denial under section 724.21A. The failure to approve or deny an initial or renewal application
shall result in a decision of approval
The Sheriff has 30 days to make a decision. If a decision isn't made in 30 days, approval is assumed automatically.
It does depend entirely on the Sheriff. I had my written form WP2 in my hand 15 minutes after I walked in the door with the proper paperwork. I had to wait 30 minutes more for my WP9 wallet card because they were in the process of setting up the computer/camera. The staff didn't like the first try. I turned down the second try. The Sheriff turned down the third try. On the fourth attempt we finally got a picture everyone thought was acceptable. 45 minutes total time that could have been 15 to 20.