Muckish

[Windy]

 What's the base of Muckish like for a wild camp ?
Up top can get draughty  .
Just that I might get down too late to start the ascent and cover the 7 sisters and may spend a night at the base.

[whoRya]

My recollection is that it is fairly stony around the base, certainly at the quarry side (as you might expect).  That said I'd be surprised if you couldn't find a nice dry spot on top of a peat hag just down below the quarry.  Myself and Rumblebum did pitch on top of it, but as you mentioned it's not often the conditions are right for that.

Are you thinking of carrying your overnight gear the whole way?

[Windy]

Yes with an overnight at altan

[whoRya]

That sounds like a challenge and a great experience.  Should the conditions allow, camping on top of Muckish would get a bit of your climbing done and set you up well for the next day.  Perhaps though you don't want to get to Altan too early.  Best wishes for the trip.