Well, you have sort of an answer in that the most rails ever gotten was twelve, which I believe is 3x around the table. just guessing that's about 18ft per trip so 54ft. So I think that if it were a straight line with regular cloth the pool ball could travel much much farther than that before the friction slows it to a stop. In the 12 rails shot the pool ball is being braked by the cloth and the rails.
I think the most I have ever gotten is four table lengths up and down, which is 28ft without the cue ball leaving the table.
I bet you could shoot a pool ball a couple hundred feet at least.
Reminds me of the old Titanic Thompson story where he bet he could hit a golf ball a mile. When the bet was right he took everyone to a frozen lake and whacked it. Everyone paid off and no one bothered to measure it.