Detailed Instructions: Given a travel related situation, and given a specific question about the situation, summarize the question into a title
Problem:I think it's better if I tell a short example:

I plan on going from country A to country B, and I find out that it is cheaper if I pass by country X.
However, the flights from A to X and then from X to B have to be booked separately with unrelated airlines 1 and 2.

Is it usually possible to ask airline 1 to automatically transfer my luggage on arrival to city X, to the plane managed by airline 2?

Or do I have to grab my luggage myself and go through customs and airport-security?

Solution:
Luggage transfer between unrelated airlines