MeterJet Spray Gun: Comments on Calibration

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Most spot treatments inadvertently over-treat the intended target with excessive spray deposit. The MeterJet Spray Gun is an effective tool to guard against this problem and accurately spot treat; however, it requires precise calibration.
Begin with a simple example to spot treat approximately one square foot with a spray nozzle attached to the Meter Jet Gun.
  • Practice a nozzle and movement technique so each trigger pull treats one square foot.
  • Attach the gun to a backpack sprayer, then pressurize and set the calibration ring to a fixed value.
  • Pull the trigger 20 times into a precise measuring container. This equates to the volume for treating 20 square feet.

If you’re utilizing pesticides on a per 1000 square foot basis this would equal 1/50 of 1000 square feet. For example, if 4 fluid ounces of spray were collected in 20 trigger pulls, this equals 4 fluid ounces per 20 square feet, or 200 fluid ounces per 1000 square feet. Convert to gallons by dividing 128 [ounces per gallon] into 200, which equals 1.56 gallons per 1000 square feet (or 68 gallons per acre). This provides a calibration setting to add the appropriate amount of pesticide per gallon of water in the backpack sprayer.