Odd how the 243 fans feel it is the panacea of deer rifles when it obviously isn't. I have never lost a deer I hit with either a 22-250 or a 243 but I have followed up some long and pretty thin blood trails for myself and others. I also note that those 243 afficionado's are generally from states where pretty open country is the norm or shoot from stands overlooking feeders. If a deer goes 150 yards and crosses a property line, even if it's carcass is visible it is lost. If your night hunting feral hogs the problem is a lot worse and the 243 is certainly no better than a 22-250 in that case. So at the no fault of the 243 I will say your right it was the fault of the guy who chose it to hunt with!
For most of my hunting career, I considered the 243 to be marginal, as I saw a lot of deer shot with it that ended up either not being recovered, or found after they had been dead for some time. Then I began to think about it, and in just about every one of those cases, the shooter was either an inexperienced hunter, or someone who simply made a bad hit. I've seen plenty of deer killed with the 243 where it worked just fine, and I've killed a few with it myself. So, as in just about any other cartridge, success or failure, can be laid squarely at the feet of the person using it.
The issue of a deer being shot and crossing a property line can happen regardless of caliber used. I have an idiot of a neighbor who uses a 300 Mag, and every season I find deer on my property that were originally shot on his. Once again, it all falls back on the shooter, and if a deer is too close to a property line, it's not going to matter what it's shot with.
