Colt is ending production of AR-15s

[sarisataka]

33. A .223 is a high velocity round.

"With less kick"- less kick than what? A comparative statement is meaningless when made about a single item.

"made to tumble on impact"- false, that is the physics of any high velocity FMJ round. The bullet center of gravity is towards the rear so when it hits a soft medium, such as living tissue, the front slows faster than the rear causing spin; much like a car with a rear mounted engine tends to spin easier. There is nothing magical about the bullet or cartridge.
Hunters, as you should know, use soft point or other designs to increase the chance of a bullet travelling straight when it hits a game animal. These types are prohibited for military use by treaty.
Note- this is an extremely simplified explanation of terminal ballistics, there are many other factors involved so it is impossible to predict if any one bullet will tumble when it hits

I use 223 in a bolt action rifle for varmint hunting. I find it quite effective on prairie dogs at 300-500 yards. Would it make a huge difference if I used .222, a popular round in Europe I have heard?

I do hunt game at times but am not a great example of a successful hunter. Often when I have the chance to shoot I decide the day is too nice to interrupt and take a picture instead. Recently my daughter and I spent are usual day in the woods on youth hunting weekend. Also as usual we failed to see a single squirrel but found it to be a rewarding experience.