[Brian Pfleuger]

A 223 with a proper deer bullet won't have any trouble penetrating a deer leg/hip/shoulder bones.

Blood loss kills, lack of oxygen incapacitates. The deer will be on the ground in 5-15 seconds if you make a double lung shot. If you don't, blood loss will likely take several minutes to kill it. Even 60 seconds at 20-30mph is a LOOONG blood trail.

No, the slug is not "more forgiving" except that it has approximately 1/3 of an inch wider path. In other words, if you make a bad shot and miss the vitals by 1/3 of an inch, the slug woud graze the vitals where the 223 would miss. In other words, you're adding 1/3 of an inch of error around a 9 inch kill zone.

Misjudging distance at 75 yards? If you think it's 25 or 150, it's like an inch and a 1/2 difference impact. You have a 7,8,9 inch kill zone.

You can't compensate for bad shooting by using a bigger gun. You have to make a good shot. A bad shot with a 223 doesn't become a good shot with a 12ga. People need to get that idea out of their heads.

The 12ga is likely to contribute to bad shooting. Recoil is bad enough that most people will sight in (maybe!) and never shoot it again until a deer is standing there. Most people flinch like hell shooting shotguns. Of course, nobody is ever "that guy" but I can't believe how many guys I've seen jump out of their skin when the gun goes "click" instead of BOOM!

I used a 12ga on deer for many years. I did fine. I only wounded two. It will kill deer, yes it will. That doesn't mean it's first or second or third choice, if there's a choice. It's not ideal. Deer slugs are a compromise by design. Why compromise on purpose? Almost any properly loaded rifle is better.

I've had my say, no minds are changing, the conversations been had 1000 times before and will be again.