I absolutely LOVE Grifball, but I’ve kinda had a small problem with it which goes back to H3. The problem is the hit registration on the hammer, sometimes I get the kill, sometimes I don’t, so I come here today to ask how do you guys play Grifball ? Are there any secrets/tips you could help me get better ?
P.S GET THE BALLLLLL !
Getting the timing down with the gravity hammer takes practice.
Be patient. This is my big downfall too, I’m not a patient tank. When I slow down and start paying attention to timing, I find I do MUCH better.
Be flexible, the connection won’t be the same game to game so being able to make adjustments (ie swing later/sooner, etc) are helpful skills to have tucked in your pocket.
Mostly though it’s lots and lots of practice. 
Play Grifball pro. It is a lot less connection dependent and similar to halo 3/reach grifball.
Take your time and try to get the timing of the gravity hammer down, and the range at which it can kill. The few games I have not done this in it goes terribly bad for me. Usually people swing the hammer outside the effective kill range so just be patient.