Bell Reducer or Flush Hub Bushing

Boom! The classic potato gun harnesses the combustion of flammable vapor. Show us your combustion spud gun and discuss fuels, ratios, safety, ignition systems, tools, and more.
mick04u
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United States of America
Posts: 2
Joined: Mon Mar 17, 2025 9:26 pm

Thu Mar 20, 2025 12:25 pm

Hello, I’m building a potato gun with a 4” combustion chamber and a 2” barrel. What would be a stronger transition from the 4” to 2” pipe, a bell reducer coupling or a flush hub bushing?
Attachments
Bell Reducer Coupling
Bell Reducer Coupling
Flush Hub Bushing
Flush Hub Bushing