I was trying to compare my hand calculations to Solidworks FEA and I was always getting a discrepancy in bolt factor of safety. I dug into it deeper and realized that Solidworks calculates bending stress for a bolt using its nominal radius for area moment inertia and stress calculations. Is there a reason for this that I cannot think of? I have been using the minor diameter to be conservative and do not know what the correct radius would be but I am pretty sure a bolt does not have same bending strength as a solid cylinder(unless analyzing portion with no thread).