I have seen a good amount of elk lost with 7mm mag, 300 wm, and 338 win. All claimed perfect hits, little to no blood trails, but animals not recovered. A few we have found at later dates, they did have two holes, but it didn’t seem to help in those cases. High chest shots, don’t leak much no matter what you punch the holes with. If your having problems try from a tree, so your shooting down on them. Or shoot lower in the chest cavity. If your still not sure you can do that, a high shoulder shot with your magnums, should take both shoulders out of play, and they won’t go no where. Still not sure, why stop at the 300 magnums, if it’s that thick and shots are not long, why not 458 win, 338 lapua, 570 nitro.? By your way of thinking bigger holes, make more blood on the ground, why not make the biggest holes you can ? And those “ real men’s” calibers will surely take out both shoulders, if you or any body with 40 years of experience behind them should know. It’s not only two holes, and yes two holes are great. But it’s where those two holes , (and what is destroyed between )are located that REALLY TRULY matters.