Slug Effectiveness
I've had the pleasure of hunting with slugs for many years, with the result of a lot of experience with bullet-on-body results. I'm sure others here have too, but I haven't seen this mentioned, so here goes.
At close range, say inside 50 yards, the far and away, hand's down winner in effectiveness on a 180 pound plus and minus animal is the foster slug.
I now use sabots and rifled barrels because of the much greater accuracy and effective range of those projectiles. They are NOT more effective in terminal ballistics at short range. This includes the newer high-tech bullets.
Sabot slugs have much less velocity for equal mass, and so much less kinetic energy. 1700 fps out of a 2 2/4" 1 ounce slug gives energy well over 3000 fp., and the 3" number is hotter but won't group as well. I just miked three that I recovered from fleshy critters and they are consistent in expansion at about 1.12 inches, with a big hole in the center like a donut. I don't know why they don't tumble, but apparently they don't. One out of six didn't expand.
If you hit your target solidly, these probably will not exit, which is good in your scenario. The rifle bullet type sabot slugs almost always exit.
Fosters slow down a lot faster than the smaller sabot bullets, therefore the superior behavior of sabots beyond my made up limit of 50 yards.
Now somebody has invented the "powerball" type slug this year, which is a foster type with a ball in the cavity to keep it even against the bore. They claim drastic improvements in accuracy in a smoothbore. Should lead less and more evenly too. Perfect for a defense gun that will also be used for buckshot (rifled barrels are terrible with shot). PLEASE somebody give me test results on this one.
Low penetration is best with shot, as has been said. I can't be sure of this 5 yards or less range, so's I prefer to have a lethal option a bit farther out, and that means slug. Shot is much less lethal at more than bedroom ranges, and the pattern up close is so small that your hit probablity is not much better. (Try head shooting a turkey at ten yards when you are excited). Lot's of folks miss. Penetration of the more powerful fosters is much less than the sabot bullets. So called "killing power" is greater too. No contest, unless this ball slug is as good as advertised.
Sorry if I rambled, but this is interesting to me. Now, I wish someone would post some test results from a variety of sabot slugs. Maybe that should be a seperate thread?