I keep waiting and hoping to see, hear or read about muzzleloader hunting with big bore calibers. Unfortunately everyone seems in a rush to turn their smoke pole into an inefficeint version of their bolt action -06 (or .270 or whatever). I always giggle (or frown) when I see an .50 inline with a 4x12 scope stuffed with the now cookie cutter load of 150 gr of wonder pellets under a saboted light for caliber pistol bullet. The scope reticle is pre-calibrated to ranges out to 250 yards or more and the bullet isn't even .50 cal but rather .45. Just how a 250 yard shot at an animal with this rig is any more challenging or impressive than the same shot with the old .308 I haven't figured out yet. On the other hand, hearing about someone sneaking up to chip shot range and killing a big game animal with a controlled shot from a large bore and I know I'm listening to someone who prides themselves on hunting and not just shooting.
Reading the article, I can't quite get behind a load using 200 grains of FFg. I'm not so much concerned about damaging the gun (although possible with some lower or questionable quality imports) as much as I wouldn't want to waste the powder. I'll bet a significant amount would end up unburned on the ground. Much more than 120 gr would be too much & I'll bet the best loads for efficiency and accuracy would be between 90 and 110 grains.
What does "gauge" mean anyway? As used here gauge means the number of round lead balls the same diameter as the inside of the barrel (aka the bore) that it would take to weigh one pound. It takes 12 lead balls the same diameter as a 12 gauge barrel to weigh a pound. The smaller 20 gauge would require 20 balls of that barrel diameter. The larger bore 12 gauge would require 12 lead balls of the bore diameter to weigh one pound.
In general the number of pellets in a shotgun shell...