Birdshot = Too much surface area, too little penetration. Shallow, bloody, but not deadly. under 10 yards, its very deadly, will render things unrecognizable
Slugs = Too little surface area, way too much penetration. Most of the round's energy is lost to whatever's behind the target, instead of getting dumped into the target. say what you want, Every deer I have shot with a slug has dropped in its tracks even though they have gone through and through. There is a lot of energy in those things
Sabots = See slugs... just not as bad due to expansion in the target.
Buckshot = Enough size to penetrate, great energy deliverance. The ideal. again tracked a lot of deer shot with buckshot, did not find all of them. Also know of a shooting where suspect was shot at several times, was hit several times, but was able to flee and run for some distance. He is now alive and well serving a life sentence.
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The difference between the slug and the rifle rounds mentioned is that the slugs are about 1/2 - 1/3 the speed of the round, but 6-8 times the lead. Same amount of energy, per se, but much more momentum. Those rifles are dumping energy onto the target, while the slug sails through.
If overpenetration's not an issue, slugs will do just fine, it's just that they have much more recoil than shot.
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