Actually shorty shotguns are one of the easiest and least expensive (registration wise) class III's you can own. They are defined as AOW - any other weapon. Basically any other weapon that doesn't fall under the "normal" class three definitions. You can register an AOW for under five bucks! Same thing as dealing with a full auto - go to a class III dealer to do the paperwork.
NOW - to get to the chase. A 16 inch long pump gun seems like a bad a** weapon to have right? Trust me, you yank the loud button one time on a breeching weapon with a three or three and a half inch round in it and that will be about all you want of one-a those ever again. The term "breeching weapon" which is what really short 12 ga pumps are generally known as in LE basically refers to a 12 gauge master key. There are special frangable breeching rounds that are used and simply the muzzle of the weapon is placed against the door frame at the point where the lock bolt goes in. Note too that the member of the tactical team doing the door "unlocking" will have a full face shield as well as guard dog style safety glasses and heavy gloves. Obviously when breeching a door in this manner, stuff tends to fly! You can bet there are very slim few standard domestic doors and latches that won't yeild to this method of unlocking.
The new 870 is a bit gimmicky for me. The modular function is a neat thing for tactical use, but for home defense the standard 'ol 870 LE version or Marine Magnum are hard to beat. There IS NO better home defense weapon than a 12 gauge pump - period! I prefer the Remingtons because of the steel reciever. Mossy's are good pumps but the alloy reciever is a concern for me - but hey, I like to play with ammo loads.
At present I have - shall we say, a few 870's. I have played around with different configurations and chamberings (3 1/2 as opposed to the standard 3), sights, stocks, etc. Remington makes the 870 in 3 1/2 mag in sporting configurations but not in any normally available LE or tactical models. Again, sort of like the shorty's you gotta trust me on this one - a 3 1/2 mag tactical pump is a bit of overkill (pardon the non intentional pun). And you for sure don't want to waste any time trying a standard Remington top folder stock with a 3 1/2 magnum - IT HURTS! The 1/8" rubber pad on the butt plate is to keep the butt from scratching up the top of the barrel or heat shield, it DOES NOT do anything for your shoulder!
You guys know that I'm a die hard FAL and 1911 nut. BUT, when things go bump in the night it is a Surefire and laser equipped 870 pump with Wilson Combat tritrium rifle sights that goes with me on patrol! :right: