I wanted to do something un-necessary in every way.
That lead to me making it have one giant plunger tube.
I'll skip materials because if you want to do this you'll read.
First, you'll want to cut a 20.5" long piece of 1 1/4 pvc. In that you'll want to goop a 1" to 1/2" bushing (I think), that is wrapped in e-tape for snugness, and has some padding on it.


Now cut a 1.375" polycarbonate circle (1/4" thick). In the center of that should be a hole that cpvc can slide through easily.
You'll Want to attach that to the back of the plunger tube by 3, 3/8" 6-32 screws. They need to be in the triangle pattern for it all to fit.

Now you'll want to sand about 10" on each side of the plunger tube down. It should make a rectangle flat area. You can see how it fits in the triangle pattern in the above picture.

Grab a knife,wire cutters, pliers, and dremel, and diddle the hell out of the shell.


Make a plunger head on a cpvc endcap. It is in order 1 1/4 fender washer, 1 1/2 rubber fender washer, 1 1/4 rubber fender washer, and #8 finishing washer.
This is held on by a 3/4 8-32 screw, and a 8-32 locknut.


Cement some cpvc on as your plunger rod. When it is in the shell it should stick out the back about 1"-1.5".

The spring is a section of 9662K31. It has about the same power as an AR-15 spring, so a stronger one is needed.
Cutting the catch notch is annoying. First everything should be in the shell and assembled. I pulled the plunger rod back as far as it would go then I had my dad mark a line where the shell ended on the cpvc. I then cut a slot about .3" wide and 1/8" deep on that line.

The catch was cut out of 1/4 polycarbonate. It is a 2"x1" rectangle. You only need one slot for a catch spring. I neglected to take measurements of where the hole is, so you can do it on your own. The catch spring should be quite strong.


Close it up, and your done. I will probably put a bolt through the front so the plunger tube won't rotate.
You need the duct tape on the back because in the process of making the shell fit you destroyed those screw ports.
First is just the gun.
Second is the gun with a 16" barrel
Third is the gun with a 16" barrel and cocked.



In ending, I need to find a better spring, and just do fine tuning on the gun.
As for ranges it is late, but I did shoot two shots. With slingshot stefans they cleared my driveway and the road. (My driveway is about 100ft, and the road is like 25ft.)