Threaded connection, internal pressure question

Hi there! Take a look at the drawing attached, it's a rough representation of a cylinder under pressure, yes there are some imperfections like missing o-rings, but imagine it is tightly sealed, the question is how much internal pressure can it handle before it brakes at the threaded connection, I found how to calculate the shear strength of the threads, but I don't know how much internal pressure can this threaded connection handle. Obviously, I can calculate the wall thickness of a cylinder with Barlow's equation, it will not apply to the threaded part of the cylinder, because the outer thread will definitely add some strength to the minimum wall thickness of the threaded part.
I need somebody to solve this problem without FEA, and explain me how to do it, in imperial units.