My well has been operational for about a year in a new home, and this has been an issue really since day 1. I have a 44 gallon pressure tank my cut in pressure is set at 45psi and my cut out pressure at 65psi. I have 45psi in my pressure tank. I noticed when water was running there would be a momentary loss of pressure and then it would return to normal instantly. I mean this occured in a second or less.

Correction:

After reviewing other threads in this forum I drained the pressure tank and using a good dial type gauge reduced the pressure in my tank to 43psi (2 pounds under the cut in pressure), but the problem persisted. I used my tire gauge (at the pressure tank valve stem) to determine the pressures while the pump was cycling and found the pressure gauge on my system was faulty. Using my tire gauge I adjusted the pressure setting on the switch to a 40-60 cut in/cut out setting and reduced the pressure in my tank (empty) to 37psi. Wahlah problem solved. My problem resulted from the tank being completely drained of water when the switched called for the pump to come in which meant the system was momentarily starved for water. At my current setting there should be about 2 gallons of water in the pressure tank which eliminates the problem. Moral of the story pay a few extra bucks and get a good liquid filled gauge.

nice job diagnosing