Number one poaching round is the .22 mag and you don't think the .243 will work ? my Lord, I thought I was posting to those that knew a little about cartridges and hunting. I've popped more deer with a .223 than most have ever seen in their lives. Do you think I use the 30-30 because it doesn't work, yet the .243 has twice the energy? For 60 plus years the .243 has proven itself to be a more than sufficient round for deer.
Deer are not wearing Armour any more today than they were 60 plus years ago. Get a grip and stop with the Texas heart shots! There is not a rifle made I could not harvest a deer with. Try to actually hit a vital organ.
Have you ever gone done south? I've use a 38spl out of a S&W model 10, a Star BM in 9mm, a .22 mag Marlin, a Savage .223, 10mm 1911, 44mag pistol and rifle, 30-30, 32sp, .357 mag revolver, 6.5x55, 308, 30-06, 7mm rem.mag.. There are those of you that think the .243 won't cut the mustard? Give me a break! It's time you hit the range and actually got up off the bench and shot free hand. Three shots, 5 seconds at a pie plate 100 yrds away.
By the way, a 12ga 3"mag slug out of a rifled barrel will be able to take a deer at 200yds if you know where to hold.