RE: .243 Big Game Animals
Not looking to highjack the thread, but I know several guys who use a .243 for caribou with complete satisfaction...They are not that tough and they do not tend to run off into the thick s*** when wounded, as deer and elk usually do..
IMHO, a rifle in the .270-.280- 30-06 - 7mm Rem Magclass is ideal for caribou..The only reasonI mightuse anything more powerful is to defend myself from what might come to TAKEmy caribou, I.E a hairy volkswagon... That's why I've carried a .338 or a 9.3 x 62 on a couple of my Alaska caribou hunts..
To get back to the original question, a .243 is definitely too light for moose, despite the fact that it will kill one under ideal conditions...
The natives canoe up along side moose and shoot them with .22 rimfires , and I'm sure they shoot plenty of moose with thier .223 ARs and Mini 14s, BUT that does not make those calibers a good choice for moose hunting.. I watched a video of my Inuit guide's 10 year old son shooting a big polar bear with a .222, but that hardly qualifies the .222 as a good polar bear gun...
A more sensible minimum would be a .270 with premium 130 to 150 grain bullets...