11 replies to this topic

[KaneTheMediocre]

I originally intended to make 2 writeups, but since almost everything in the VLTS needs to be duplicated in order to make a BATS, I’m just going to show how to make a BATS, with notes on the minor differences in VLTS construction. Both of these guns use HAMPs, my writeup of which can be found here:

http://nerfhaven.com...t=0#entry266827

A dick-waving video showing a few hamp guns, including both the VLTS and the BATS, can be found here:



Descriptions:

The VLTS (Vacuum Loaded Tagger Shotgun)

The VLTS is the simplest possible HAMP gun, and is basically a barrel attached to a HAMP, with a few minor additions to enhance useability. Well made VLTSs shoot a single tagger about 60’, and blasts of 8 taggers (or 1 tagger and whatever else fit in the barrel) 45-50 feet. Shotgun loading is faster than multi-barrel shotgun attachments, since they are all dropped (not pushed) into the same hole. A weakness is mediocre range, and aiming is a bit trickier, since the dart is fired while the gun is being “pumped”. Also, the gun has no magazine of any sort, so you need to fill your pockets. Ammo goes fast if you use the shotgun feature.


The BATS (Bolt-Action Tagger Shotgun)

This is the staple of my HAMP arsenal.



This gun has all the same firing properties as the muzzle loader, but includes a longitudinal magazine that holds 8+-2 darts, depending on the size of your gun. Reloading is bolt action OR muzzle load. Bolt action loading requires the gun to be tilted back and leveled prior to cycling the bolt. As a result, refire is similar to an RSCB (sp?) clip. Beware, cycling the bolt while the gun is tilted back can cause a jam as 2 darts will stack on top of each other, and get pinched in the breach. Although the bolt-action can be cycled repeatedly for shotgun loading, personally I think it’s easier to just stuff a handful of darts down the barrel.

Construction:

CAUTION: It is very important to thoroughly deburr the sharp edges that result from cutting these parts, and even more important to clear all of the chips away. For the steel EMT, that means at the very least blowing / pushing some wet toilet paper through the barrel, repeatedly, from both sides. You don’t (or you shouldn’t) want to be shooting metal chips along with your darts.


1. The Elbow: There are lots of ways to do this, the easiest of which uses a 1/2” piece of braided tubing. The method described here is much more difficult, but improves airflow a great deal (1/2” braided tubing has about ¼” ID). Another method, which has good airflow (but not quite as good as below) starts with a ½” hole, and nests PEX in CPVC, and CPVC in PVC. Most hardware stores carry impact coupling tools to achieve this:



The PEX-CPVC-PVC method only requires a 1/2" hole, which is usually easier to make cleanly. The disadvantage is slightly reduced airflow, more gap between the barrel and the HAMP, and lots of quality time with the hammer.


1a. Drill a 5/8” hole in your HAMP, a close to the plugged end as you can put it without damaging the end cap. This is not a terribly easy task, as drills will get often get stuck and stall out frequently, or they might quickly and unexpectedly make a triangular hole.



A drill press and / or a good clamping system is very helpful for getting the hole to start on the curved surface. Beware that a powerful drill may grab the piece and pull it out of your hands or clamp, spinning it until it hits the post of the drill press our your face (WARNING: facial impact may not stop HAMP rotation). With patience and/or frustration, and a wee bit of scissor work at times, it can be done with a hand drill.

1b. Insert a small piece of CPVC and the CPVC elbow into the hole, and put the PVC coupler on the CPVC elbow (the elbow fits loosely inside the coupler).



1c. Affix these parts. Since my hole looks like it was made by a 3rd grader with an icEffeminatek, I used plumbers putty / epoxy putty, which smells bad, takes time to set, and gets on your fingers.



I have no doubt that this could be accomplished as well by some choice or combination, of duct tape, hot glue, e-tape, and/or ticky tack. Ticky tack is the best for making a good seal, but doesn’t provide any useful mechanical bond. This can be fixed by adding duct tape, which is mechanically great, but doesn’t make very good seals. Hot glue is good if you want to make a messy clusterfuck that seals great until you use it on a hot day. Or a cold day. Or you drop it. Just make sure it’s at least sort of airtight and stays on to your satisfaction. Don’t feel like you need to stick with my methods in part 1; I know I haven’t.



2. Cut off 3’ of 1/2” EMT Steel Electrical Conduit for the barrel, and 3’ of ¾” PVC for the magazine.

All my other BATS have used thinwall ½” PVC, but I was running low, and besides the stuff is hard to find for many people. If you’re making a VLTS, you CAN use ½” PVC for the barrel, and in fact get slightly better range, but it will jam occasionally, and require some unpredictable amount of notably obscene finagling to extract the dart.

3. (BATS only) Breeching the barrel: How you make these cuts is entirely up to you—my first BATS breeches were made using only a hacksaw, plus a great deal of blood sweat and tears. I don’t particularly recommend that method, but it can be done. A dremel tool will make these cuts easier, but I should note that the fastest and cleanest way to do this, and the way I did it, is with a mill. But, normal people don’t sacrifice their bedroom to become a machine shop and sleep in the living room of their apartment, so I imagine most of y’all will be dremeling this.

3a. Cut a breech into the barrel, ½ way deep, from 6” to 10.25”
3b. Cut a breech in the magazine, ½ way deep, from 6” to 10”
3c. (optional) Cut slots in the magazine, so that the ammunition is visible. Make sure that whatever slots you cut are large enough that you can get a knife/scissors in to deburr the inside edges.








As you can see from the pic, I didn’t really cut the magazine as described—I got fancy with the mill, hoping to avoid the need for cardboard flanges later (I still needed them). If you want to mimic that, feel free, but make sure the opening allows darts to very easily drop out.

4. (BATS only) Making a breech cover: This is one of the few times where there’s really only one way that I know how to do this. Cut and split 5.5” of thinwall ½” PVC. Remove material such that the profile is a C shape, covering about 270 degrees. Put a hole ½” from the end, and entirely above the middle of the circle the tubing used to make, through both sides. Stick your preferred bolt-pin through it. This needs to be strong, so I recommend 1/8” to 3/16” steel. If the hole is not the same size as the pin, you need to put something on there to seal it. When complete, the breech cover should snap on and off the barrel, with some difficulty, and the pin should not prevent the breech cover from sealing the breech completely.



Also put some duct tape on the pin, both to keep the pin from sliding out, and to make a safer, more comfortable grip. I didn’t do this until much later in the profile.



VERY RARELY thinwall PVC can be found that slides smoothly over EMT tubing—If you find it, buy as much as you can, because its hella useful for things like foregrip breeches. If you have it, you don’t need to cut it into a C shape, and if you have room on the barrel, you might want to make it longer, and cut the pin further from the end, in order to better seal the breech.


5. Attaching the barrel: This step is MUCH easier if you use hose instead of an elbow in part 1, since you don’t have to space out the barrel to compensate for the elbow height.

5a. Use a small piece of thinwall ½” PVC to mate the barrel with to the PVC coupler. Duct tape or E-tape could be used instead if need be. Superglue the thinwall PVC on to the end, to keep the barrel from sliding into the coupler.



5b. Stick the barrel into the coupler, and put something between the HAMP and the barrel to compensate for the elbow height, then tape it down to the HAMP. I used a 1/2” square wooden stick, but a mess of cardboard and duct tape works alright too. Do everything you can to keep the barrel and the HAMP parallel.





If you used a hose in step 1, there’s no gap to space out and you can just tape down the barrel. If you’re making a BATS, you need to make sure that your spacer and whatnot do not interfere with the action of the breech. I didn’t have to worry about this much with the ½” square wood, but with a mess of duct tape, you might be limited to attaching at the front and rear of the HAMP, leaving the middle (where the breech travel lay) open. Also, if you want to try gluing the barrel, that’ll probably work fine, and in fact will better keep the barrel from moving sideways once dry. I’m a duct tape man, and so that’s what I use.

6. (VLTS only) Put a screw in the very rear of the barrel, to prevent darts from being sucked back into the gun. This wouldn’t hurt for a BATS, but normally the bolt-pin takes care of this.

Edited by KaneTheMediocre, 25 February 2010 - 12:59 AM.

[KaneTheMediocre]

7. The Plunger Guide: HAMP plungers seal best when the plunger is close to coaxial with the casing, and for practical use, you don’t want to be able to pull the plunger off the gun, or hit the air exit tube on the inside.

7a. Position the plunger in the HAMP so it’s about ½” away from hitting the air exit tube.

7b. Find something that slides nicely on the barrel. I used ¾” PVC for this, but in the past I’ve used ¾” EMT, rolled up cardboard with duct tape, etc. It’s not critical. Put it on the barrel.

7c. Find something to space out the barrel. I used the same ½” square wooden material as the barrel spacer, but I needed to wrap it in duct tape to pad it out a bit. Again, cardboard/newspaper/whatever is fine, it just needs to take up space

7d. Tape it all together.



I avoided taping all the way around here, because I wanted a good sliding surface to present to the magazine, but usually I go all the way around, and it’s not really a problem. In retrospect I wish I’d gone all the way around, as it would add a lot of strength. It seems to hold up all right as it is, but I suspect I’ll break it at a war and end up retaping all the way around anyways. Also, there’s a bit of extra plunger length past the spacer/plunger guide, which I ended up cutting off later.



I wish I’d kept it on now, as the extra size made it less likely to pinch my hand when I fire. I ended up piling on some duct tape to make the grip more comfy and less likely to pinch myself, but it took a long time to do, and I’d rather just have the extra length.

7e. To avoid pulling the plunger out of the gun, you need to make an out limit stop. This can be done easily by pulling the plunger out as far as you want it to go, then winding duct tape around the barrel at that spot. Don’t let any yarn show, as entering/exiting the tube can scrape it along the inner edge of the outer HAMP tube, and damage the plunger.



8. The barrel tip: I used ¾” PVC for this, although I’ve used thinwall 1/2” in the past. I strongly recommend 3/4” PVC, as it provides a very blunt tip, which is better for safety in case you accidentally bump someone (No one wants to get stabbed with EMT). It’s also crucial if you want to barrel tap, although from both a safety and gameplay perspective, barrel tapping may be the most idiotic rule ever to be put forth for nerf warfare. But that’s another discussion. Anyways:

8a. Make sure your out limit stop is wound to close to the OD of the barrel tip.
8b. Wind more duct tape around the barrel, to the ID of the barrel tip. If you have much barrel left (as I did), you may need to do this in 2 places.



8c. Cut off some 3/4” PVC, about 1/2” longer than the amount of barrel you have left, and slide it over the barrel. It shouldn’t wiggle too much with the duct tape spacing it out inside. Tape it on, winding duct tape around the crack between the out limit and the barrel tip

8d. Make the tip orange. This step is not optional. I don’t care if the whole thing is spraypainted purple, do not underestimate the imagination of a policeman. I use orange duct tape, but you could paint it if you like. I’d recommend painting the tip prior to attaching it, if you’re going that route.



If you’re doing a VLTS, congradulations, you’re done. If not, feel free to pretend that it’s a VLTS, and shoot a few darts before continuing. You’ve earned a break.


9. Attaching the magazine: Getting the magazine to stay on straight is more art than science so far. I’ve done it with nothing more than duct tape, but nowadays I use two-sided tape or foamy sticky strips to set it in place, and then tape over that. Make sure that the breech in the magazine is aligned such that it begins slightly after the barrel breech, and ends somewhat after the breech ends.


10. Making the dart stop: I use a wooden dowel for this, but I’m sure something similar could be achieved in other ways. I’ve used bits of cardboard taped into the magazine in some of my BATS, although that is best done before the magazine is attached.

10a. Cut the wooden dowel at a slight angle.
10b. Wrap tape around the dowel in two places, to the ID of the magazine.



10c. Slide the dowel into the magazine, and position it such that the slope of the dowel will push the dart downwards after it is completely above the breech. It shouldn’t need a push, as this is gravity fed, but you don’t want it to get stuck on the dart stop. The slope makes sure that this can’t happen. Mark the spot on the dowel where it exits the back end of the magazine


10d. Pull out the dowel rod, and wrap tape around the marked spot such that it cannot be pushed any further into the magazine than you want it. It will be easier to tape down if you wrap tape around to the OD of the magazine.



10e. This wasn’t necessary until I used ¾” PVC for the magazine, but I found that I needed to glue (I used wood glue) on a piece of cardboard to extend the slope at the end of the dowel rod. I put scotch tape over it to make sure it wouldn’t come off. There shouldn’t be anything tugging at this piece, so I don’t expect it to be a problem.



10f. Put it in, and tape it down. The cardboard should spring back once it leaves the magazine tube.



11. Add some cardboard flanges around the breech to keep darts from falling out. The cardboard can’t go any lower than the bolt-pin, since the pin moves back and forth beneath the flanges. Bigger, stiffer flanges will better retain the darts, but smaller, looser flanges will make it easier to fish out darts in case of a jam. There’s plenty of room between these extremes where a dart will NEVER escape, and jams are easily cleared. In any case, if you use the blaster properly, it will never jam. There’s no clever technique here, just cut out some cardboard and tape it down.


12. Add a thin, bent piece of cardboard to the tip of the magazine. Use a thin strip of duct tape to cover the cardboard—if you don’t do this, the darts will wear out the cardboard over time. Tape it down by wrapping the barrel and magazine in orange duct tape, or use regular tape and do something else to re-orangenate the tip. This should allow darts to be pushed in, but not allow them to fall out when the blaster is pointed downwards.





Congradulations, you’ve built a BATS. Fill the mag with taggers and shoot something.

[Daniel Beaver]

Yay, you finally posted these. Kane's blasters are seriously cool. They need handles, though.

Edited by Daniel Beaver, 25 February 2010 - 01:12 AM.

[minsc]

I really like the breech system, almost like an actual shotgun. This also is much more compact and air efficient than an RSCB, which decreases in range as the clip empties. Have you tried this system with tighter fitting darts such as mega stefans? I'm curious to see how well this would translate to homemade darts.

[KaneTheMediocre]

I really like the breech system, almost like an actual shotgun. This also is much more compact and air efficient than an RSCB, which decreases in range as the clip empties. Have you tried this system with tighter fitting darts such as mega stefans? I'm curious to see how well this would translate to homemade darts.

Most mega stefans fit tightly into the EMT barrels that I use. My guns require a loose fit, so they would jam. The air pressure and volume that these HAMPS put out is basically the same as what lungs do, so if it works for a blowgun, it will work for a HAMP. That said, if you want short range, poor accuracy, and short barrels, you CAN make 1/2" darts shoot out of a 3" piece of CPVC. You really have to slam the cylinder closed quickly to build pressure faster than it leaks out around the yarn though. I have made a VLTS (the singled version) with PETG barrels, which shoots stefans/slugs through cardboard. Ryan tells me this indicates 100+ ft range, and it indicates to me that I need softer ammo (like streamlines) to safely use it.

Edited by KaneTheMediocre, 27 February 2010 - 07:13 PM.

[minsc]

Ok, that's what I figured, I suppose having a lot of semi auto shots and a passable range can be more useful than having a single long range shot. Perhaps I'll try with really thin foam and petg, if I ever buy some.

[KaneTheMediocre]

Ok, that's what I figured, I suppose having a lot of semi auto shots and a passable range can be more useful than having a single long range shot. Perhaps I'll try with really thin foam and petg, if I ever buy some.

Actually, I made a PETG barrel insert that converts the whole system for use with streamlines today. I made a video, but I need to cut out the first 7 minutes. So far, I've been through 3 video editing programs, all of which allow me to cut out the first 7 minutes, but none of them are capable of SAVING the resulting video.

Anyways, if you want to use slugs/stefans, the PETG barrel insert is the way to go as opposed to a straight up PETG barrel, PETG is too flimsy for 3' barrels.

[Doom]

It's unfortunate that I did not have the time to look over this in too much detail until now. The simplicity of the design is very impressive. I'm looking forward to making something along these lines eventually.

[QuidProNihil]

I made a video, but I need to cut out the first 7 minutes. So far, I've been through 3 video editing programs, all of which allow me to cut out the first 7 minutes, but none of them are capable of SAVING the resulting video.

If you're on a PC, Windows Movie Maker can save it, but you need to select "publish movie" instead of "save project". - that has tripped me up more times than I'd like to mention.

If you're on a Mac, I believe the program is called iMovie, and it can do the same thing. I'm much less familiar with iMovie, though, so I'm not 100% certain as to how it saves, I just know it can.

[KaneTheMediocre]

I made a video, but I need to cut out the first 7 minutes. So far, I've been through 3 video editing programs, all of which allow me to cut out the first 7 minutes, but none of them are capable of SAVING the resulting video.

If you're on a PC, Windows Movie Maker can save it, but you need to select "publish movie" instead of "save project". - that has tripped me up more times than I'd like to mention.

If you're on a Mac, I believe the program is called iMovie, and it can do the same thing. I'm much less familiar with iMovie, though, so I'm not 100% certain as to how it saves, I just know it can.

"Save movie file" was the syntax I believe. I wasn't saving the project, it told me that the source file or directory did not exist. They definitely did exist of course.

Other programs have saved in odd formats, or in one case saved the original 9 minute clip. I'll just film it again, or take pics. I've been scrambling to prepare new things (darts, and blasters that use them in bulk) for a few wars happening around now.

[BBBB]

@KaneTheMediocre Is there a write-up for the BATS? If so please pm me the link.

[Langley]

@KaneTheMediocre Is there a write-up for the BATS? If so please pm me the link.

This thread is from 2010. If you want to get in touch with Kane, you can PM him. If you've reached the daily limit for PMs, you can wait until tomorrow.