I think to be considered a ''pistol'' the ''shotgun'' had to come from the factory with a pistol grip installed and not a traditional buttstock.
I have an H&R and put a pistol grip on it. I chopped the barrel down to 21'' when it came across my mind that I forgot to measure OAL!! It even says on the grip "Use with 22'' barrel or longer"
Anyways, it measures EXACTLY 26'' and that is only because the pistol grip is angled backwards a little as it goes down. Lucky thing. Then again, I could have just got a stock and chopped it down to 18''.
"All skill is in vain when an Angel pisses on the flintlock of your musket." -Dean Speir