Unless
You have an experienced fire team that has worked together.Zero hour is impossible.
Everyone is rushing,bumping each other off Ledges et cetera
I just did a fire team and each of us only died twice and we died just about 25 seconds short.
F*** stupid
-
I can assure you doing normal in 20-25 min with help is very obtainable. Legend prob not so much for your average player. Not sure which youre referring to tho.