So, long, long ago, (about 1.5 years) I crudely modded a BBB for a friend by adding a CPVC barrel, and a EMT blowgun.
A few months ago, I started playing with homemade breeches for the Nerf clips, starting with the Autobow (I'll post a writeup for that sooner or later, but you pretty much NEED a mill). So, I called him up and asked to re-mod his blaster to take clips. He complied, and I gave him an early Autobow prototype as a loaner.
The integrated blowgun provided a convenient linkage for the breech to move relative to the air outlet, so I started by placing a T connector on the end of the blowgun. This preserved the ability to shoot taggers from the blowgun. Next, I machined a PTFE Tube to 1/2" OD, and 3/8 ID", except for the tip, which was made ~.520 to better seal with the breech, which I planned to make with .527 ID x .625 OD Aluminum (MC # ). This tube was nested in CPVC in order to glue it into the air outlet
I realized that clips would grip much better on the .719" OD of the ' 1/2" ' EMT, so I hammered the aluminum tube into the steel EMT, then cut 3.25" long breech into the resulting nested tubes.
In order to hold the clip straight, I needed to make a clip-mold. Here's how to do that. with pics from the AutoBow Mk II. I'll get a writeup for that up soon, i hope.
1. Put paper under the clip, and fold it out of the way
2. Put the assemblage in a vise, or otherwise prop it up so that you can pour hotglue on it. Make sure you have a clear workspace without clutter which may be damaged by the hotglue, or just get in your way.
3. Make sure the clip is aligned with the breech
4. Pour on the hot glue. I usually put something on top of the hot-glue which is friendlier to attaching stuff, or otherwise helps to reinforce, since hot-glue isn't known for its structural strength, or it's effectiveness as a glue. Ideally, all we should ever use it for is moulding to a shape. For the AB, I used a 1/2" square stick.
Once that was done, all I needed was to attach the breech to the blowgun / PVC Tee, which was achieved with a cut-down Tee connector and a stub of PVC.
At this point, the raider-BBB (because I was using drums at this point) worked perfectly, in spite of the fact that the breech/barrel assembly wobbled all over the place, and the PTFE tube would usually slam into the end of the breech, rather than passing through it. So, although it worked, it really shouldn't have, so I added the laquered plank as a gusset, which kept the barrel pointed slightly downwards, and ensuring that the PTFE tube would properly feed through the breech. It was still a bit wobbly at this point, and I didn't have much in the way of available attachment points, so I just taped/hot-glued a reinforcing board, which I also intended to support the raider drum from the side (it doesn't at this point).
Yes, some screws would be a good idea here. I haven't gotten to it.
Now, more pics:
edit 6/6/10: The glue between the diagonal plank, and the straight plank/PVC T came undone. So I added a couple wood screws between the straight plank / diagonal plank, and a screw between the bottom of the T and the diagonal plank.
Not the cleanest mod I've done, and it's certainly not up to HAMP standards of durability, but I haven't seen something like this posted before. Also, this mod does not require you to unscrew the shell.
Has not been war tested, and I don't know the ranges. I'm guessing the streamlines get longshot-ish ranges, which is about as much as you can do before streamlines swirl out of control. Better dart barrel fit, or even just a longer barrel could improve it I'm sure. Also, if you need a bit more range, the tagger blowgun on top will easily to 60' flat. Which is good enough for a stock ammo war IMO.
Edited by KaneTheMediocre, 06 June 2010 - 04:45 PM.