That depends on the way you do the experiment. If for example you pull the plunger away from the solenoid then the measured force will be larger than the calculated force because you have to pull against the magnetic force and the friction force (from the side force because the plunger is never concentric to the solenoid). On the other hand if you use the solenoid to lift a weight from a distance you will need more current than the calculated force needed to produce the force to pull the weight, because again you need to overcome the friction force. Therefore, when you will calculate the force for the measured current you will find that it is higher than the weight.