Given the general rule that a pound of lunch meat serves about 3 people (with a little extra to allow for those that love to load up their sandwiches), you would need about 27 pounds of chipped ham to feed 80 people. But if this is for a potluck I wouldn't necessarily plan that every single person at the party would want to sample my dish. If it were me, I'd prepare less than that.
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it's a variant of the southern y'all, it has the same meaning. yinz = you 'uns
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As a regional dialect, Pittsburghese is fascinating! Maybe because I grew up hearing it, I don't know. But some of the words are weird: warsh, redd-up, scootch, gumband, jagoff, dahn tahn. The accent isn't real strong where I live, if you want to get the full effect you have to go closer to the city. If you can't visit Pittsburgh and want to hear how those words are supposed to sound you can search You Tube for a sample of Myron Cope, he was a Pittsburgh sportscaster for many years and he was famous for his strong Pittsburgh accent and use of regional colloquialism.
