Interpolated impulse response for fraction delay?
Unfortunately fractional delays are much more complicated than this. Your example would create a filter where delay and amplitude are significantly dependent on frequency. 
I strongly suggest reading http://ieeexplore.ieee.org/xpl/login.jsp?tp=&amp;arnumber=482137&amp;url=http%3A%2F%2Fieeexplore.ieee.org%2Fiel4%2F79%2F10273%2F00482137.pdf%3FisNumber%3D10273%26arNumber%3D482137%26isnumber%3D10273%26arnumber%3D482137
and
https://ccrma.stanford.edu/~jos/Interpolation/