Showa 29, or 1954. It is worth a bit more than newer types, around 20 cents. Is the edge reeded? (this is a confirmation of my date reading) It is also bronze, not brass.
That's a common mistake that I was plagued with. I am using the Krause book now and it is good. I have an excel spreadsheet to validate my argument (row 1 is year 1, row 2 is year 2, etc.)
That's what I used to use, before I got my Krause book. When you add 29 to 1926, the year "1927" becomes the first year you count. However, 1926 is the first year of the reign meaning you need to subtract one year from your answer, or better start a year behind the year that the emperor's reign started (ex. 1925+29=1954; year 1 is then 1926).