Addition to original post.Found a James Mccoy in the 1910 census for Pennsylvania,age fits as to year he would have been born in Ireland.Married to Ellen,has son John and two daughters Ellen and Mary.He is a lumberer.How do i make sure he is the real mccoy,i know,i know.
One possibility for the James McCoy you found in the 1910 is a marriage of James McCoy to Ellen Quinn in Philadelphia in 1897.
If you've seen the actual 1910 census image, it might have a column for age at marriage or the year of marriage or the number of years married.
You can see James McCoy's marriage to Ellen Quinn by going to the Philadelphia, Pennsylvania marriage index on the FamilySearch website at
https://www.familysearch.org/search/collection/list#page=1®ion=NORTH_AMERICAUnfortunately, you won't get to see a marriage license. But you can search both names to verify that the marriage certificate number is the same for the two of them.
In any case, you can't be sure if this is your James McCoy. One way to find birth information for James McCoy is to search for some indication that he was naturalized as a U.S. citizen and get hold of the naturalization papers. The 1920 and 1930 censuses might have that information--assuming that he lived to be counted in those years and that you find the real McCoy.
John