When squirting oil in the cylinder between compression checks does not result in any increased compression, it is usually a sign that something in the upper end is amiss.

Unless there is a hole in the pistol... If that's the case, timing and mixture could be the culprit.

1977 CJ-7, fiberglass body, AMC 360 w/ headers, DUI ignition, Edelbrock intake and Holley 4150 carb, TF999, Dana 300, 4.56 gears lockers, York air comp, 4" susp lift, 2" body lift, BFG 35" M-T tires, Megashifter, AGR pump & box, REP8000 winch.