Garmaine Staff asked 3 years ago

If I (US citizen) come into Istanbul on one airline (Turkish) with a checked bag, and then fly out later to Kazakhstan from the same airport that day on a separate ticket on another airline (Astana), do I have to go through customs and immigration to get my suitcase and go back through the departure screening process to catch my other plane? Is a visa necessary just to do that, even if I am not leaving the airport? My layover time is about 6 hours