iamthatcat

This shotgun attachment is inspired by a blaster I saw with a 6 way pvc manifold and a barrel on each way. It's for the lulz and what not. It's basically 4 inline clips wedged into a 1 1/2" endcap. I apologize in advance for the lack of pics illustrating a few areas, I think I lost a few.

This will take a fair amount of air to operate. I used an expanded 4b which was fine. Titans and the like would be great. I imagine it can be scaled down or up as I didn't put any math to this at all. It holds 50 1.3" darts (squished in up to the muzzle) and fires 30+ at good pressure out to 80'. At low pressure I get 15 darts at what seems like safe velocity.

I use a manifold inside the endcap which can be optional. I haven't tested this without the manifold to see if there is a performance difference. It does make building easier and produces a bit more durable absolver. A simple dart stop would work in it's place. It can be loaded by removing each barrel or by simply pushing 2-3 darts down each barrel and ramrodding them in. I am showing it fitted with a threaded 3/4" cpvc female coupler. It would work with other configs of course, but this fit my application. Thanks to Nerf Doctor for helping me finalize the coupler setup. Longer clips &/or barrels would work too. I'd like to try petg barrels on this for weight soon.



Materials:

1/2" conduit or pvc (4x 6 3/4" or longer)
1/2" cpvc (4x 8 1/2" or longer)
2x 1/2" cpvc couplers
1 1/2" pvc endcap
3/4" female coupler (or similar)
Thick acrylic sheet (or polycarb/similar)
Super glue (thin and gel) or Epoxy/Solvent weld

Tools:

Dremel w/drum sander/drill bits
drill bits/corded drill/drill press
files/needle files (nice but optional)
Coping saw

We'll start by making these sub assemblies. Coupler, endcap and clips. To prepare the coupler I chopped the front off to remove the slip fit section but kept the area behind the gasket. I had to file off a protrusion as well.



First I trimmed the 4, 1/2" conduit sections for the clips. I cut and flied them down to 6 3/4" but I wish I had left them 2" longer now. I glued 2 sections together by laying them on a flat surface and using a tiny drop of superglue near the ends to secure them temporarily. Glue 2 more sections together and then test them for true before gluing up the 4 in a square. If they are wonky just whomp them apart with a mallet. I dribbled thin superglue down the join of each clip and set it aside to dry a while. I then chopped my cpvc couplers in half & filed them flat carefully. I had to remove a little material from the side of each coupler in 2 places to get them to sit right.



Let's prepare the endcap for the coupler. I cheated and used a manufacturing mark in the bowl at the center (kinda) to start the hole for the coupler. We can adjust for straightness when we glue it up. I also chopped a bit off the front of the endcap for weight, less fitting work and better access later.



I went up through a few sizes to my 5/8" bit (largest I have). Obviously the coupler I am using is much bigger. Some "custom" fitting with a dremel will be needed.



I marked the progress needed from the inside. I show the coupler on the other side for illustration. It should be possible to eyeball & adjust this dang closer to centered as you open up the hole.



Eventually I could whomp the coupler in most of the way. We'll finish fitting it later, just remove the coupler for now.



Now let's fit the clips. I marker, dremeled and filed the ends of the clips that interfered with the endcap.



Here's how it should look from the outside when fitted.



I used thick acrylic for the manifold, but poly or pvc would be better here.



I held it up to the back of the clips and marked the areas to remove. I removed that material with drill bits, dremeling and files.



I super glued this onto the back of the clips. I wish I had used one more coat of glue now that I see this pic. I did need to dribble some thin superglue into that area after it cured.



I cut the barrel material, filed the edges square and chamfered both ends with the reaming tool on my tubing cutter. I chamfered one end a little less and called that the muzzle. Ok now we should have this:



At this point I dry fitted everything to adjust for straightness. Fine filing of the hole for the coupler accounted for some adjustment and I filed the flat area on the clips a bit to make up for some more. I used the blaster out of the shell at this point. If using threaded couplers tighten the female to it's final tightness (might have to clean & grease the threads) before lining stuff up.



I marked where things needed to go to line up and glued in the coupler with gel superglue. I allowed that to dry a while and re-tested the clip in the endcap for straightness with the tape marks. I then applied a bead of gel superglue to the back of the manifold and to the endcap liberally. I whomped the clip home and set it aside for a day to cure. I added some thin superglue down the endcap, around the clip area in 2 layers.



Here it is fitted to a helix 4b reshell.



I added a little tubing to spread the barrels horizontally.

These darts have surprised me with their durability and accuracy. They resemble glue domes but have less death potential, imo. Straight silicone is injected into a syringe to allow for precise application. A cavity must be burnt or drilled into the foam. It's pretty easy, which works for me, and is also fast. The main thing is to keep the silicone away from the edges of the foam no matter what. Any overlap will result in squibs. I show pool noodle foam and stock darts but I'm sure this will work with fbr. I used dap silicone rubber sealant from kmart. Give the darts 5 (ugh) days to cure. My janky makeshift hotglue gun/burning tool is not ideal but workable.

Here's the silicone and syringe.



Inject the silicone into the syringe. It's possible to get 20+ darts out of one filling. A tube of silicone caulk should provide 200+ darts



I made a cavity in the foam with a wonky makeshift tool. It's a dremel grinding stone shoved into my hotglue gun's nozzle and secured with copper wire. I sink it down to the 2nd coil into the top of the blank, being careful to align it and sink it clean. This isn't the most accurate method of course and needs some work.



I add some half moon cutouts of foam to the hole in the stock darts to get a good even weight.



Inject in the silicone from the bottom up, being careful to fill the cavity thoroughly. The syringe allows for precise application which should make getting consistently weighted heads easier. Keep the mound and any residue away from the edges of the foam.



I used a small square of moistened chamois type material wrapped around my finger to shape each head. You can let them skin a bit and adjust the head shape. I got almost no shrinkage.



These take forever to cure. I found that 3 days was not enough for this brand. 5 days resulted in more durable darts. The heads will still come out if ripped out but withstand quite a bit of abuse. Range is comparable to my hotglue domes. Accuracy is good although I have had more bad darts with this method than my usual. Durability is good if properly cured.

My dollar store carries some nerfy stuff. My favorite so far are these arrows. The are labeled "Silly Shotz" & use a rubber band for launching. I've found them to have decent performance out of UMB's and the like.

They fly fairly accurately with some punch! They hold up to some power too. My little reflex launches them to 45' flat and can send them 55'+ angled. They work fine with a UMB's missile launcher for an adapter. They have a rubber band running through them. Better range might be had by modifying them a bit. They are not solid foam. That's probably why they don't destroy themselves.

They had that little bitty reflex and I had to pick it up.

SSPB's need too many pumps to be really effective as a sidearm. Here's my go at a pump replacement. The factory pump is simply chopped off leaving an inlet for the new pump. I used a water gun pump from a Buzz-Bee Equalizer. It's about 1" in outer diameter and 6" long. A thinner pump would likely add pressure and perform better. A 45 degree PVC elbow is used to support the pump and act as a grip. I show 2 sizes of tank expansion. I think the smaller will be sufficient for most. I am trying a wye out on the larger with good results.



Here are most of the required parts. You will need some tubing to nest around the pumps outlet. I used the outlet pipe from a UMB pump. You may want some 1/2" thinwall PVC to move the grip back.



First let's chop up the SSPB. We'll use various methods to keep debris out of the guts. A bit of foam works well for the pump inlet. I used grease for the valve this time. A little electrical tape keeps dust out of the trigger. Twist the barrel peg out with needle nose pliers. Stuff a piece of crumpled up, wet paper towel tightly down the barrel to protect the valve from debris on this rough cut. Pull the pump handle all the way out. Chop your SSPB here.



Clean all the debris away and add some white lithium grease to the valve area. Try to get it behind the cross or remove the cross with a razor knife. This will keep debris out. I also removed a support boss at this point. It will get in the way of the grip later.



Chop a little more to get past the cross without hurting the valve. Scoop out the debris and grease with any small tool. I also used a q-tip to clean the valve out thoroughly. If done carefully there should be no need to flush the tank.



Chop a coupler in half, just behind the ridge.



I chamfered the area around the valve a little just for experimentation's sake. Glue on the coupler. While it's drying we can build and fit the tank.



Now onto the tank expansion. I used a PVC stub for the larger tank. I'm not sure if there is a real performance difference. It's a bit trickier to shape than a CPVC stub. Both tanks use a 1/2" PVC elbow. The larger tank uses a PVC endcap instead of a nested CPVC one. Nest a small length of PVC inbetween the elbow and the endcap for the larger.



Dremel the area under the PVC stub until it's paper thin.



Carefully slice out the center. Sorry about the recycled pic.



Afterwards I melted the edges a bit with a wood burning tool. This is optional. It's easy to see that support boss that needs to be removed in this pic.



Test fit the tank. I kept everything close to the SSPB so I could glue it in a few places for strength. Solvent weld the tank together and let it dry. I affixed the tank to the SSPB with super glue but epoxy or solvent welding is a good choice too.



Ok let's move on to the pump. I used a fairly slim pump but a slimmer one would raise the pressure in the tank a bit more. This pump needed the 90 degree bend chopped off to fit of course. This is still to small to nest into the SSPB's pump tube so we'll need a small section of tubing to make up the difference. The outlet tube from an old UMB pump is perfect.



Here it is chopped up and test fitted. I used the tape as a guide to line up the pump with a mold seam on the bottom of the SSPB. Solvent weld everything in. I added a filet of superglue to the join later for extra strength. Now we can fit the pump support/grip handle.



Here it is glued up. Add some glue to the elbow (or thinwall spacer) and pump face when assembling, to support the back of the pump well.



Chop 2 slots down the elbow. The length of the slots can be manipulated to change the grip dimensions. I just twisted the waste material with needle nose to remove it. I needed to dremel away some material from inside the elbow on the shorter grip. I also needed to add a (notched) 1/2" thinwall spacer to the longer grip. Later we can add a length of PVC and a 1/2" endcap to the grip. I used thinwall for weight. Glue the elbow both to the pump and to the SSPB for strength.





Now let's make the pump work. I used a piece of 1/2" PVC (conduit) with a piece of CPVC whomped into it. Shave a portion of the PVC to fit inside your pump. The CPVC is whomped in and reamed out until the pump tube slides through it freely. I affixed this with electrical tape for easy maintenance. I added an additional piece of CPVC to the end of the pump to affix my elbow and pump handle.




Shot de Money.



The smaller expansion takes 3 pumps for 100' ranges. The larger works a homemade wye at the same ranges but takes 5-6 pumps.

I needed a dart door and I wasn't quite satisfied with other designs. I looked through my materials and tried this out. Imagine my surprise when it worked! This consists of a cap, door, seal and band. I used a 1/2" PVC male threaded coupler for the cap. There's a nice hole the right size through the top and a nice area around the slot to guide the door. I used some scrap acrylic for the door. I had a rubbery phone cover for the seal. There's a white band from some packing materials to secure the door to the PVC clip. Common tools are used except for a hole punch. I used a make-shift one that was .53 inches in outside diameter.

Here's the fitting we'll start with. Saw away the threads first.



File the top flat. I removed material from the bottom of the fitting for weight. I started a slot with a fine ceramic disc. The slot needs to be even across and at the right depth.



Here's the depth it should be at from the inside.



Now let's cut out the door. I used a coping saw and went slowly.



Start the fitting by dremeling or filing the edge of the door smooth. Be careful not to remove too much material or you will need to make another. It has to fit across the inside of the coupler tightly. Try it's fit in the slot and adjust the slot's height so that the door starts to fit. The corners of the slot needed the most attention. Eventually the dart door will fit in the slot about halfway. Then just file the corners carefully, keeping the file parallel with the other side. Trimming a bit with a razor knife saved time and was precise.



Here's the finished slot from the front.



I quickly added a hole and a band to secure the door to the clip. Now let's add a seal. I used an old phone cover. Oh how times have changed. I pushed the cap into the material with some force to mark it. I then used a fine point marker to mark the cut. I used small, sharp scissors to cut out the seal.



I scuffed & dusted the cap and seal. I have found this material to be tricky to glue so I want to get some surface area. I used gel superglue. I laid a bead of glue above where the seal would rest so that the seal would (hopefully) pull the glue down into the gap. I pushed the seal against the door at the edges carefully with a piece of cpvc. Pull the door out and wipe off the glue that gets on it.



I added a filet of thin superglue around the seal.



Let it dry and then put the door in the slot. I eyeballed my punch into the center of the bottom of the seal. I twirled it a bit just to mark the rubber and see if it was centered. I adjusted and then spun the punch through the seal until I felt it start to bite into the door. Make sure to cut all the way around remove the punch. That'll do it!



Here it is mounted to a homemade wye with a small clip. I tested it by clearing out the darts, pumping it up, holding my finger over the muzzle & firing. It seals perfectly. I added a little white lithium grease to the seal. Don't push the cap on too tight over the clip or it will impair the door's movement. It stays open when pulled out by the tension from the band. Perhaps not as ergo as other designs but it performs well and seems sturdy so far.