  The spallative production rates of Lithium, Beryllium and Boron (LiBeB) are a
necessary component in any calculation of the evolution of these nuclei in the
Galaxy. Previous calculations of these rates relied on two assumptions relating
to the nuclear physics aspects: the straight-ahead approximation that describes
the distribution of fragment energies and the assumption that the major
contributor to the production rate arises from single-step reactions between
primary cosmic ray projectiles and interstellar medium targets. We examine both
assumptions by using a semi-empirical description for the spall's energy
distribution and by including the reactions that proceed via intermediary
fragments. After relaxing the straight-ahead approximation we find the changes
in the production rates and emerging fluxes are small and do not warrant
rejection of this approximation. In contrast we discover that two-step
reactions can alter the production rate considerably leading to noticeable
increases in the efficiency of producing the LiBeB nuclei. Motivated by this
result we introduce a cascade technique to compute the production rates exactly
and find that the results differ only slightly from those of our two-step
calculations. We thus conclude that terminating the reaction network at the
two-step order is sufficiently accurate for current studies of spallation.
