A slight correction and more details on the wounding of PaulHamilton Craps, my Great-great grandfather:
His medical records put the wound half way between the sternum and shoulder joint on the left side, one inch below the collar bone. The bullet exited one inch below the shoulder blade. This likely happened as the troops of Drayton's Brigade knelt behind a stone wall surrounding a peach orchard on the SE corner of Sharpsburg at around 1:30pm. They were probably facing the 9th NY, also known as Hawkins' Zouaves. As the 9th NY crested the hill just 30 or so yards in their front, the 15th SC opened a devastating fire. The New Yorkers regathered their senses and returned fire, over-running the Southern position and driving them through the town.