Yes using a smaller nozzle will affect the distance.
www.hunterindustries.com/Resources/PDFs/Instructions/Domestic/lit379w.pdf
Did you use male adapters on this job where the leak is? I had a problem with Spears male adapters.
I had to make three free service calls recently from their latest design leaking. I talked to a Spears representative about the problem. I'm not the only one to complain to them. He gave me the old part numbers and I bought 6 boxes.