Foam A Nature - Nerf Double Barrel Shotgun

Well, here's a thing I've working on for a long while now. Though the performance isn't as high as I was hoping for, this double barrel is still pretty fun to play around with.

Compatible with buckshot(Rival), Mega and Slug(single dart) Spring Thunder shells.
Shells available here:
https://www.thingiverse.com/thing:3210080

You will need the following materials:
-music wire for custom bent spring(see video below)
-seventeen M2.6x12mm counter sunk head screws
-one 2 inch chicago bolt
-one 1 3/4 inch 6-32 bolt
-10 coils of a K25 spring
-(at least) 2 small springs (I used Nerf catch springs but I think mechanical pen springs would also work)
-4 1/2 inch length of 1 3/8 inch ID, 1 1/2 inch OD polycarbonate tube
-17/32 inch brass (cut length to match trimming jig)
-9/16 inch brass (cut length to match trimming jig)
-two 1 3/16 ID x 1 3/8 OD x 3/32 cross section (also know as "dash 123" O-rings)(suggested hardness 70A)
-two 14mm ID x 19mm OD x 2.5mm cross section O-rings (suggested hardness 50A)
-two 1/2 inch x 1/8 inch aluminium flat bar (approx. 4 1/2 inch lengths. Use slot in printed part to trim to size)
-one 3/16 inch diameter extension spring (approx 1 1/2 inch in length. Trim length until the spring is taught when extractor is in un-primed position)
-three 7 1/2 inch lengths of 6-32 threaded rod
-seven 6-32 nuts
-1/8 inch round metal pins (I used nails cut to length)

If you want the the shoulder stock you will also need the following hardware in addition to the hardware listed above:
-two 6-32 threaded rods (7 3/4 inch and 8 1/4 inch lengths)
-four 6-32 nuts
-5 1/2 inch length of 3/4 inch wide elastic band

If you want a shell carrier you will also need the following hardware in addition to the hardware listed above:
-four 6-32 nuts
-four 1 inch 6-32 bolts

For more information on how all these parts go together please refer to the tear down video below.

Some parts of the ejector are rather finicky and will need some light sanding in order for them to function properly.

October 2020 Update:
added "barrel_topStripe_picatinny.stl"
This part replaces "barrel_topStripe.stl". So, you can choose if you want a flat top or a picatinny rail on your barrels.