I had the same issue with my 84 H16.
Picked up another sail set from ebay recently but this was even harder to raise.
I also recently picked up another mast recently that is from a later period, guessing 90's.
This weekend I tried the newer mast with the newer and older sails, what can I say they went up a dream.
Previous to this I was going through silicon lube like no business!
So what was different about the two masts?
The earlier mast had a really small luff feed grove. It was about 3" in length but the later mast has a considerably longer groove I would guess around 6 - 7" and with a wider flare.
What I found was happening on the old mast was that the luff was contently catching and fighting against the smaller feed groove.
It also caused an acuter angle against the luff and the boom as it was almost raised causing the last foot or so to be even harder to raise even while feeding.
Hand feeding is required if sails are tight as one should not be yanking hard on the halyard but rather feed in and then take up the slack with the halyard. Yanking on the halyard causes the luff to tighten in the mast even more since there is a slight curve in the sail luff and by pulling hard on the halyard causes the mast to bend slightly to meet the luff which causes more friction.
My new to me mast and sails goes up and down like a pole dancer do large to David Grey's come sail with me! Wondering now weather she is a bit loose!
So what type of mast luff groove do you have?
I know how frustrating it can be particularly when on your own and other sailors have arrived after you setup sailed and returned to be still there trying to raise the main!
I bought a H14 to compliment the H16 for this very reason