This time of year I usually have good luck hunting customer rolls from the bank. Today I picked up a box of red customer rolls. In the first ten rolls I only found 5 copper coins. The rest (495) were zinc/copper. I finally fell victim to a copper hoarder. I guess I will hunt the rest of the box, but it is tempting to just re-roll the ten and dump the box to my dump bank.
I don't bother to keep copper either. I look for any missing dates in my collection and also errors and variaties. But if all you get are '83s to current, you can't find much.
Weigh the entire roll with a good scale. 50 x 2.5g = 125g + a gram or two for the wrapper. 50 x 3.11g = 155.1g + the gram or two for the wrapper. at say 128g + the weight of the wrapper it has either an extra zlincon or 5 copper cents.