[Steigerwald]

It really does not matter whether there is a clog in the barrel. Assume there is one by some random occurrence. That would mean that the bell reducer which is not pressure rated would be experiencing the full pressure. Not only that, but when you open the valve, there is a sudden change in the pressure which causes a shock to the assembly making it more likely to blow out.

Every component on a project like this one has to be rated to the absolute maximum pressure that is to be put in. If air flows through a component, there is a chance that it will be at high pressure. Possibly not under normal conditions, but you should always plan for the worst.