I agree with Socrates the intent is to have round or near round shot particles. Because the atoinzation process yields made different shape it is necessary to determine acceptable shapes as defined in Figure 1. Marginal shapes including nodulated, elongated, and twins are acceptable as long as they number less than the allowable amount listed in Table 3. A nodulated marginal particle would be one containing at least one attached shot particle. An Elongated particle in most shot specifications define them as; a particle whose length is twice the width of the particle. Twins would be considered as two particles attached that are approximately the same size.
