I don’t see how a comet that gets as close as 724,000 miles from the Sun could possibly survive. The temperatures in the corona alone would bust it up nicely.
Crossing the “Roche Limit” should pulverize any aggregate mass, so no worries about a cannon ball. Understudy for a “clay pigeon”? Anyone know if the plane of the projected exit trajectory approaches Earth’s orbit if comet debris exit in a fan pattern? Suitably coated metallic objects have survived near ground zero nuclear detonations due to ablative shielding effects. Some of the comet fragments could survive shielded within a cloud of vaporizing debris post breakup.