The smaller pigs taste better, and unless you are looking for a head mount, skip the Boars, and go for the sows! The boars, especially the big boys, are rank, and the meat tastes like it!
Unless they have been caught, and clipped, and then released. The fighting sheild is mainly on the back, around the neck and past the shoulders. It is a thick grisly chunk of skin, and is very tough. It protects the hog from tusks, and teeth, and fangs, and claws from big cats. Like they said, the key is a good arrow, and "SHARP" head! And also as they said, use the heaviest bow you can shoot well. Tough?!
I shot a sow quite a few years ago, at about 15 to 25 yards, with a .357 magnum, with 158 grain, semi jacketed hollow points. I hit her the first shot, in the front section of heart, and she took off like I had fired in the air! I thought I had missed! I then shot her again, and hit her in right front leg, between the shoulder, and elbow, and it shed it's jacket, and lodged in her left front leg, at about the same point. My buddy, was to my right some distance, and shot her from the hip with a 12 gauge with 3 inch magnum triple ought, and blew an inch or more hole through her jaw, and when she turned, he shot again, and severed her spine, and that ended it! She was less than 15 feet from him when he first fired, and she was heading right at him. When I cut her open, the front half of her heart, had been severed almost in half, and her liver was like chunks of thick jelly, and her insides was full of blood. My bullet was mushroomed beautifully, and lodged in the skin on her left side! She dressed out at about 100-120 lbs. However, there were some "HUGE" hogs in that area, of Perry Florida. After I got home after that trip, I bought my S&W Model 29, .44 magnum!
But then again a .22 short in the forehead will drop them like rock.
Wayne