Good grease gun that doesnt lose prime???

[2busy]

So after use, I release the spring as to not leave tension on it. Is that not proper protocol?
Seems if you store it with spring engaged, it'll leak and/or push the plunger past all the grease which I've had one do.

Never thought I'd be considering a $100-$200 grease gun!!!

In hot weather tension on the spring can cause what you described. Nature of the beast. Even battery operated ones have a spring to push the plunger.