Lee reloading presses are ok for a start off but the dies scalles powder throwers are cheap junk.
If you want accuracey buy RCBS
Oh my what a sweeping statement
and one that is obviously total cobblers
I do prefer the Lyman scales that I picked up used some years back but I did start with a set of Lee scales and apart for the adjustment which i didn't like they are fine and accurate. As for Lee dies I had one set with caused problems when the expander withdrew and was stretching the neck shoulder but these were replaced by Lee. Now I have dies made by Lee, RCBS, Lyman and Redding and in all honesty they all performa about the same.
Now i have never used the Lee powder perfect measure but know those that have and they didn't have any problems providing the instruction of use were followed. I have an RCBS Uniflow again picked up used but it not in use due to lack of space so i use:-
Horror of Horrors
I use lee Dippers with the scale
I do not have check weights, keep meaning to acquire some but have honestly never found the need, I periodically break out the CH scales (also picked up in a trade) and check the two against one another. The chances are both being out by the same amount is too small to contemplate.
Now back to the OP and the question. Your doin soemthing wrong... Go back to the beginning and read the instructions...................... Yes READ them
follow them and you should not have a problem. It's something simple I'll wager that is causing this. Like did you rune powder through the measure first to coat the insides like Lee say?
Did you check the thrown charges in the scale pan? Was the scale zeroed and sat upon a flat level surface? You really need to read through the instructions and follow them to the letter and which such huge variations you also need someone who has been successfully and SAFELY hand loading for some time to go through it with you as there is a major error here and a potentially unsafe one.