Hey Wabi and Screwbolts, a word of caution about wads from milk cartons.

This may have been a one-in-a-million occurrence, but I want to tell you about it anyway. Up until last year I had an original 1800's vintage Belgian made double barrel 20 Gauge that I used to use wads cut from milk cartons in. These were the cartons with a light paraffin coating. Now this gun had a fairly rough bore, but was solid and shot well.

One time when I was "vigorously" pushing a milk carton wad down the bore there was a distinct flash and small "pop" when the wad was about a quarter of the way down. Scared the bejesus out of me. There's no way to tell with certainty what caused it, but my theory is that friction of the rough bore + the paraffin coating + perhaps a granule of powder trapped where the edge of the wad met the bore all came into play. Anyway, for the rest of the day I sure pushed those wads down gently, and stopped using paraffin coated wads after that.