I recently picked up a S&W 3000 police trade in with the 18" "Pol. Cyl." barrel and speed feed stock. It's marked "Pat. Pending". Do all of them say this or do some have patent dates?
I have two of the model 3000. Both police riot gun turn ins. One is 18 1/2" barrel five shot. The other a 20" seven or eight shot. Not sure, never tried to load eight. Both function well and one stays by my night stand.