As my handel suggests my cailber of love is the 358 WCF; it takes no prisnors!

Have never had to track any game I've shot with it. With that saying, the wife has a 243 (hell I have two) I've loaded some good varmint/target rounds; but (I know I may start a firestorm)

I 've found it lacking in deer size game. This is with shamefuly factory loads especialy, and regular bullets. Hence why I've thought about switching to Barns; used them in everything from my 257 Roberts Imp, 7X57 Imp, 308, 3006, and the mighty 358. THEY WORK! Trouble is what would be a accurate hunting load?
Her rifle is a sweet almost new condintion 788 w/a 22" Bbl; my newest piece is a Rem. 700 w/ 18" Bbl both factory barrels, the Rem. 700 is brandy new virgin, w/ syn stock. Taking a young hunter with me to GA, in a few weeks, thought it would be a good platform for him. Any help out there?