I am briefly touching base on dis-assembly of this shotgun in my pulse build thread, but figured I would put a little more detail here.
First off, this thing is awesome. Damn near real. It comes apart nearly identical to a real 870.
Attachment:
20141209_185216_HDR.jpg [ 191.78 KiB | Viewed 6642 times ]
Attachment:
20141209_190702.jpg [ 317.28 KiB | Viewed 6642 times ]
There are really only 3 differences that I am aware of. Two very very minor. One kind of unique.
-Minor difference 1 = Trigger assembly pin size. In the real 870 the rear pin is larger than the front. On the APS CAM870 the pins are the same size. Because of this, side-saddle accessories for real 870s wont fit without modification. Most other accessories should be plug and play if you wanted to use aftermarket parts to mod one up for actual airsoft purposes.
-Major difference = Slide removal. On the real 870 there is a spring/tension bar on the inside of the body that must be pushed in to release the slide. On this airsoft shotgun the little thing that looks like the tension spring does nothing to release the slide. Turns out on the top of the inside of the body is a knob that blocks the bolt assembly from sliding forward.
Attachment:
20141209_185052.jpg [ 152.89 KiB | Viewed 6642 times ]
You can access this "block" by first removing the trigger assembly. Then you remove the two screws in the silver 'block'. Once you pry the silver thing out the forend/grip/slide assembly slides right out.
-Super Minor difference 2 = Removal of the fore-grip is similar to a real one as well, except that there are only 2 'notches' in the retaining nut. The usual "tools" with the "teeth" pattern may not work here. Once you get something to grip those (i simply used needle nose pliers spread out) it unscrews and the grip can be removed.
Attachment:
20141209_185301.jpg [ 123.29 KiB | Viewed 6642 times ]