Hydraulic lifter ?

Engine, 67 273 with lunati hydraulic cam & lifters & stock adjustable rockers. When adjusting valves to zero lash + 1/2 turn, I can feel the plunger movement on some lifters & the plunger feels rock solid on some of them. Is this normal? Just go to top of plunger movement +1/2 turn, run until pumped up and re-adjust?