Pretty common for modern manufactured 1911s to have very little if any barrel throat, the rifling runs right up to the chamber mouth, and it goes without saying that it probably won't "plunk" a round assembled with a .452" boolit unless it is stuffed completely into the mouth of the case and has very little if any of the boooit going into the throat.
CZ USA is entering the 1911 market with an all American made pistol, they are a quality conscious manufacturer with a solid reputation but for us handloaders and casters, not so much. Here is another 1911 made for j-words and j-words only.
I contacted them through their FB page to ask about barrels:
Their reply:Glad to see CZ making a 1911A1 pistol! In the USA too! Tell me about the barrels. Are they hardened like many of your other models? Will they easily chamber handloads using .452" bullets? Many current 1911s won't until they get barrels throated. We would just as soon see a company consider the fact that thousands of their customers are handloaders and would like to see products suitable for those customers right out of the box, it doesn't take much! Kudos on the new (old) warhorse, I hope it does well in the market!
I did read that their barrel is stainless, which would mean that it may be able to be cut with a throating reamer so it will plunk and shoot .452" cast boolits reliably.CZ-USA The barrel is hardened, but the chamber is not over sized. Watch your OAL and make sure you use a factory taper crimp. Remember that shooting reloads in CZ firearms is not covered under warranty.