This write up is well overdue. It should’ve been done in August before school started. In the middle of cutting the stock with a table saw, the wood shot back and ripped my fingernail off and stuff so I couldn’t finish it for months. I finally got around to finishing it so here it is. With the increasing rarity of the PAS and the fact that I don’t even think the ball shooting version is available on Amazon anymore, I decided to make one myself.
This is my initial designs for the gun. It was a late night and I didn’t realize the gigantic problem with this priming design until the next morning. I couldn’t believe I thought it was that simple. You can decide my initial stupidity for yourself:
Materials-
1.5” PVC
1.5” PVC endcap (the squared off type, not the rounded one. I found one in Lowes by accident
A PVC reducer to go from 1.5” to .5”
.5” CPVC
Some 3/4" wide wood for the stock and pump guide
Spring (I used a [k26])
Catch spring (I got one out of a BBUMB for the springs from the buttons for integrations
Various screws
Small piece of sheet metal, polycarbonate or whatever material you like to fashion a trigger out of
1 zip tie
Metal shim or rebar or whatever this part is called, see the write-up for specifics on it
Various bits of PVC for the inside of the blaster
3.5” section of 1” and 1 ¼” PVC for pump grip
Construction-
Stock:
First I went to Google images and searched for ERTL pump action shotgun and picked a good sized image. I copied it into Microsoft Paint, cropped it so that I got the stock and some of the gun. I changed around print properties so it would fit onto one page and increased the percentage of its size until when I went to print preview and looked at it at 100%, I held up the 1.5” PVC to the screen and gradually increased its size until the PVC was the same size as the one in the picture. Then I printed it.
Next you tape the printout to the block of wood and check one more time that the size matches. You need to sketch out 13” of wood for the part that extends to the front of the gun. At this point you use a scroll saw, jig saw, hack saw or whatever you feel like using to cut out the stock.
Then you round out the corners of the stock and sand them so that the corners are all rounded and smooth out all the cut marks. I did this with some files and sandpaper.
Next I made the plunger tube. I cut a 13.5 section of 1.5” PVC. The reducer I got had an extra section to put the PVC in the back so I cut it down so that the dead space becomes literally nothing and then I put some wire to stop the darts from getting sucked into the plunger tube. Next glue the reducer into the front of the plunger tube so that it looks like this:
Make the spring stop out of some bits of PVC that fit inside the PT so that the CPVC fits inside of it without wiggle and the spring cannot go through it. It should be relatively small, about 3/4” wide. Mine is a drilled out piece of 1/2" pvc inside 3/4" pvc inside 1" pvc inside 1.25" pvc
The plunger rod is .5” CPVC with whatever seal you would like at the end of it. I used a rubber grommet just because I like how easy it is to adjust it to get a good seal from it. Then I put a notch in the rod for the ring catch by calculating how much compression you want and then add the width of the spring stop. The notch should go halfway into the rod. You can’t tell from this angle but mine is and then I rounded its edges for a better catch.
I padded the front of the plunger tube with the tip of a BBUMB missile.
Put the spring over the rod and slide the spring stop on after that. Drill 2 holes on the top and bottom and screw it in place. You want the spring to be compressed a little so that you maximize air delivery. Next assemble the catch. You take a piece of PVC that can freely slide over the rod. I think mine was a piece of 3/4”. Then follow the drawing to make the catch. The process is the same as my last write-up and that of the other ring catch blasters with PVC tees just by replacing the tee with the PVC. Follow that by drilling a hole a bit bigger than the CPVC in the center of the cap and just put it on the end. Then cut the CPVC so that it just makes it past the end cap. You don’t screw it on yet.
Once all that is screwed into place except for the end cap, put something in the front of the gun so that you can push the plunger rod back and see if the catch works. Bang it around and make sure that it won’t disengage unless you push on the screw. Use this time to test the air seal too.
The next step is to cut out the sights that go on the top. I just looked at the picture and traced them out. Then I glued the front one on and drilled a hole so that the screw goes through it.
Next we will work on the pump action portion of the PAS. You need to find a metal that can bend reasonable and spring back to shape. It will push the plunger rod back. I found mine in my basement so I don’t know exactly what it is. It is 1/16” tall and about 1/8” wide. It should be about 13” to 15” when you are done but don’t cut it down just yet. This is what it should look like. Don’t mind the background, which should be part of another write up soon…
Take your stock and cut a groove in the top so that the piece of metal can pass through it with ease without coming above the top. This is the point at which I got my middle fingernail and nail bed partially ripped off by the stock shooting back at my finger. Although one of the interns in the emergency room was very intrigued when I told him I was making a homemade Nerf gun. So unless you have a lot of experience with a table saw, don’t use one. I finished with a Dremel after my finger fully recovered.
Next you need to cut a groove in the plunger rod so that the metal will pass through it. Ignore the angle at the end of the groove. It is supposed to be just a straight groove
At the end of the plunger tube, you need a way for the metal to stop and be able to push the rod back. I found this in my Dads workshop so I cut it down and screwed it in.
Next you need to drill a whole through the plunger tube like this so that you will be able to push the rod back.
The spring stop should get a hole in it like this:
In the end, this should be accomplished:
Now we will make the pump grip. I just took a 3.5” section of 1” PVC and 1.25” PVC and cut them down like this:
Then you attach them together and put two screws in them. You then need to put the pump grip next to the stock and gun to find where to cut the metal so that when the pump slides on the stock piece it will stay at the front of the gun.
Then you bend the metal like this and solder/weld it on.
When that’s done, you need to trim back the front of the stock so that the grip can slide on top of it. Also make the final cut to the length that it needs to be. When it is all assembled it should look like this but the catch will get in the way. Try to figure out what the last step meant by looking at it assembled like this because it is hard to put into words.
Next up is the trigger. Use a drill and a Dremel to make this sort of hole in the top. You need to work it until it is just right. Then cut the back of the stock so that it can be assembled like above. One screw should go where the picture is through the stock and into the end cap and PVC. The second should go under the pump grip and into the PVC so that it acts as a spacer and a way for the pump grip to stop before falling off.
Use a cutting disk to cut a grove so that the trigger will fit inside. The trigger is just a simple piece of whatever material you want cut out like this so that it will use a screw as a point to turn on and the second part on top will push on the screw to release the catch.
The screw should remain stationary while the trigger can move back and forth.
Then drill 2 small holes for a zip tie to make the trigger guard and hot glue it into place.
If the gun un-catches in this state but remains cached without the stock, the hole under the trigger needs to be enlarged.
My last step was to take it back apart and paint it. Unfortunately I’m not the best painter and it was a giant pain in the ass.
Well here's the final product. I think it does its job as a replica pretty well.
And here it is primed. This is by far the most dangerous part about this gun. Just like any other homemade, only the builder knows its every flaw and where to put your hands and how to handle it. If you have never used this gun, you will try to put your face on the gun and might have your cheek ripped off. This is the only flaw besides the arm tiring gigantic prime. I chose this over making a tiny plunger tube inside the 1.5” PVC and gaining little power so until some revolutionary method of pump action arises, this will have to do for me. This would be a good method of priming a gun with a sheath behind it as it will make the gun considerably smaller and eliminate the need for a big pump shaft to prime the gun.
