LLigetfa
DIYer, not in the trades
What did the other gauge read when your test gauge read 48?By the way, i bought a water pressure gauge tester since I have a spigot/bib coming off the well pipes and it was 48 psi. I also filled up a 5 gallon bucket and it took 40 seconds...What would tell me about my sprinkler flow with the zone or what not.
As you discovered, your spigot cannot flow at high GPM due to the size of the opening so it is apples to oranges comparing it to your sprinkler system. You would need to replace it with a full port ball valve to measure higher GPM.