bushmaster,
Is it a US marked gun, a commercial riot gun or a cut-down?
The Stevens 620 (and various 'hardware store' marked versions) is an evolution of the older Stevens 520. It's basically a slave to fashion- Stevens wanted to keep up with the style of streamlined receivers that was then in vogue, and so they rounded off the hump-back receiver of the 520.
It's an old Browning design, the 520 patent dates back to 1903, the first 520s were sold in 1904. The 620 was introduced in 1927, the 520 stayed in production at least until 1932.
The takedown system was apparently 'borrowed' from the older Burgess pump shotgun design (see
http://www.shootingbums.org/hvr/burgess.html for pics) and is my nomination for the best shotgun take-down system of all time. It removes both magazine tube and barrel from the receiver, so you get a compact package that's easy to carry, especially when the gun has a riot length barrel.
To take it down:
1) make sure the magazine and chamber are empty. The action should be cocked and the safety ON.
2) open the action, bolt all the way to the rear.
3) grasp the grooved portion of the magazine tube and turn it clockwise (looking from the rear of the gun) until it stops. As you turn the magazine tube, its threads will withdraw the 'keystone' locking blocks from the front of the receiver.
4) with the action still open, push down gently on the top of the barrel near the receiver while pushing up on the bottom of the receiver. The barrel assembly should slide down a bit until it's stopped by the action bar, which is still in the receiver.
5) slide the forearm all the way forward till it stops, supporting both the barrel assembly and the receiver while doing so. When the action bar is clear of the receiver, the barrel assembly should side the rest of the way out of the receiver.
To get access to the magazine tube, remove the screw (use a properly fitted screwdriver) that holds the magazine end piece to the lug on the bottom of the barrel. NOTE that this part is under pressure from the magazine spring, and rests in a shallow step machined into the lug. Be careful to control it after the screw is removed, or the magazine spring will launch it for you.
With the screw removed, the barrel assembly can be separated into its component parts for cleaning and maintenance.
I'd suggest no user attempts to disassemble the receiver- it IS a Browning design we're talking about here after all. If the internals badly need cleaning, remove the stock and soak the receiver assembly in a mild solvent (kerosene in a safely secured container, or even hot water with a degreaser), then shake/blow out the excess solvent with compressed air, dry with a heat gun or hair dryer, and re-lube.
They're genuinely neat guns, the military-marked versions are bringing pretty spectacular prices these days. If yours is so marked, take really good care of it... and if it isn't, treat it nice anyway
. They're great old guns.
hth,
lpl
