There are many factors to consider in determining the value of Walking Liberty Half Dollars. These pieces were manufactured between 1916 and 1947 and have a high silver content. When you calculate the value of the coin, you need to look at values including the price of silver, percentage of silver in the coin, price of copper, percentage of copper in the coin, total weight in grams, ounce to gram conversion factor and the pound to gram conversion factor.
You should also look at other factors including the mint mark. These coins were minted in Denver (D), Philadelphia (P) and San Francisco (S). Even coins made within the same year can have a difference in value with some mint marks. You can also check the Numismatic Value Range to see what people usually pay for specific coins.
There are also ways to calculate the melt value of silver, but you probably want to focus on the above values when you are investing in Liberty Walking Halves. The price of silver and copper are the only factors that may change and they can change on a day to day basis, so you need to keep this in mind when determining values.