  We calculate the resistivity contribution of tilted grain boundaries with
varying parameters in sub-10nm diameter metallic nanowires. The results have
been obtained with the Boltzmann transport equation and Fermi's golden rule,
retrieving correct state-dependent relaxation times. The standard approximation
schemes for the relaxation times are shown to fail when grain boundary tilt is
considered. Grain boundaries tilted under the same angle or randomly tilted
induce a resistivity decrease.
