Inconsistent spray from back-pack weed sprayer

[MisterBoy]

I have a 10L or so sprayer and have always had issues with getting it to spray consistently. I'll fiddle with the nozzle until I get the nice wide spray I want, then within a couple of minutes it'll be spraying far less well. It doesn't seem to be a pressure thing because re-pumping makes little difference, I'm forever tweaking the nozzle - wasting time and getting stuff all over my fingers.

Is there a difference between good and bad sprayers and I just have a duff/cheap one? Could the nozzle need replacing?

 

[lostinthelight]

It would help if you said what sprayer you had and if a cone or fan jet

 

[JohnD]

have you unscrewed the nozzle and washed the grit out?

 

[Nozzle]

You might find the weed killer has gone claggy and it gums up the end of the lance. You'll have to give it a good shake to break up the clag, then unblock the entire hose/lance

 

[MisterBoy]

have you unscrewed the nozzle and washed the grit out?

I have a couple of times had a look, more gummy than gritty, but I think even new it did this and cleaning it out doesn't really seem to help much. I'm mixing my own stuff each time if it makes any difference.