Help with gravity/suggar addition plz - may have cocked up.

[Cully]

Have been given some grapes from a friend with Noble Mould on them. After a lot of reading decided to leave the mould on and go ahead and make some wine. So mashed them in a bin, took a gravity reading and set about Chapitalizing the must. Took gravity which was 1.070, applied the calculators on Brewers Friend and its saying I need to add 200grams of sugar to get an end strength of 12.5%. What is puzzling me slightly is that I made some apple wine last week which when applied to the same calculator needed 1 kilo of sugar, which I duly added and stirred in. I may have cocked up here. If I have added too much brewers sugar will this make the resultant apple wine undrinkable?

[jaroporter]

what was the gravity reading for the apple before adding sugar? most country wine recipes i've seen/used seem to use around a kilo of sugar per gallon. sometimes more. very few of them go into such technical details as adjusting for specific sugar content of the fruit. point i guess being, a kilo of sugar doesn't seem like an unreasonable addition, to me at least..

[Brewhunter]

Yes the apple sounds fine I will usually add between 1kg - 1.3kg of sugar per gallon,
I'd be interested to find out how you get on with those grapes

[Cully]

The must tastes fantastic. Going to add 200 g sugar to the squashed must tomorrow and take another reading. When the first fermentation dies down and I can put it in to a demijohn, will take another reading and adjust for 13% strength. The apples came from the same bloke and are legacy cookers of various types. He has Pears too but they all fell and went off quick - he is going to keep them for me next year.