Not scientific my any means. Just an observation. Last weekend I slaughtered and butchered a pig on my in laws' farm. The killing method I used was a brain shot with my 10mm 1911 Commander using my handload of a 180gr XTP traveling at 1200fps at the muzzle. Distance from muzzle to the pig's head was approximately 2 inches. When I shot it, the pig immediately dropped down on the ground and then rolled to its right side and its left leg kicked twice and it was still. I hooked it's hind legs on the cable, then cut its neck to bleed out. After I skinned it and butchered it, I wanted to venture a bit into the terminal ballistics that occurred. All this talk about over penetration with fast and heavy handgun cartridges had me intrigued. Immediately after bleeding it out and washing the body, I noticed the bullet didn't exit the skull. This is the entrance wound to the skull. I was pretty close to being on the money. The shot favored the pig's right side but was otherwise acceptable placement. Look between the eyes for a little white circle along the blood streak of its forehead. The bleeder cut. Notice the clump of very dark blood. The shot also made the right eye bulge out of the socket. Here is sucked back in a bit, but it was halfway out when I was washing it after bleeding it. After butchering, I skinned the head down to the eyes to get the jowl meat. I noted the entrance wound and stuck my knife in the hole to get a trajectory path. This is the throat opened up. Note the large collection of very dark blood. So that was the damage done to the head by gunshot. I didn't cut the head apart. I tossed it in the field and anchored it down. The coyotes and birds will clean it and I hope to recover the bullet and see what it looks like. This post is an afterthought. Now I wish I would have opened up the head and looked inside. I'm going to check on the farm this weekend and see if anything touched it. I've heard a rumor that coyotes are very slow to eat the remains of domestic animals. I actually really thought the bullet would completely penetrate the skull at that distance. I was absolutely certain it would. I waited a while for the best shot and even neglected a few because a log was underneath its head. Based on this, with the velocity at 2 inches from the muzzle versus, say, at 20-some feet during an attack, if it didn't pass through at a 2 inch shot, I don't think it would pass through at a 20 foot shot. Your thoughts on it? I've had pass throughs at much longer distances than this.