Yes like that, allows you to put more grease pressure to the fitting.

 

Came across this thread when I was recently trying to figure out how to grease this kind of fitting for the first time. After reading the thread, I ran down to my local hardware store to find an adapter for my grease gun. The guy at the hardware store showed my where to find them, but then he suggested it might be easier to use a chainsaw grease gun instead - they're designed to grease the sprocket on the end of the chainsaw bar.

I picked up a disposable one like this - it comes preloaded with grease. You can also get a refillable metal one like this . When pumping the grease, you are pushing directly down onto the fitting, therefore no problems trying to get the tip to seal into the fitting well. This thing worked perfectly - I'd highly recommend one of these guns for this type of fitting! Available all over the place online if you google chainsaw grease guns, or go look in the chainsaw accessories section at your local hardware store.