My closed bolt Ion (really)

y0da900 · 10-11-2009, 12:58 AM

I've mentioned this in discussions around here before, but hadn't shown anything. Until I uploaded the animation the other day, only a small handful of people had seen it. There's an attempt going on at MCB for and open source project, so I decided to finally share it.

It is a closed bolt spool valve (more like pressure controlled poppet, but debatable and largely semantics) that I designed a few years ago. The current working version is built around using an Ion body for ease and cheapness. I've got plans to build one from the ground up at some point, just haven't gotten around to it yet.

It works in a manner nearly opposite that of the prototype Legion Shocker and the Nova. Air enters through the side of the rear of the can (just like in an Ion). A normally open valve supplies pressure behind the valve piston, and when vented, the change in pressure bias pushes the piston back both sealing the dump chamber and opening the valve.

Focus in the design was reducing pre-expansion volume for the firing air, and a smooth flow path. I would say it was successful as I get almost 2,300 shots per 20 ounce CO2 tank from it, albeit at an unverified velocity, but more than fast enough to break paint in game just as reliably as any other gun shooting normal velocity and at a good speed for trajectory (so probably in the normally accepted velocity range). Testing over a chrono should happen shortly.

Current versions have the step that stops the firing valve in its forward travel on the piston portion, not in the power tube for ease of manufacture and eliminating the further restriction it caused (currently at .241" across). Getting that step in there was a pain. I've since made the cut out section between the 2 tail o-rings go further to the front (reducing the length behind the middle o-ring) in an attempt to let the chamber start filling faster and reducing shoot down. I haven't tested the functionality of this modification yet.

The rear plug can be moved in and out of the gun, and it very effectively alters the velocity. While backing it out as much as possible while maintaining functionality seems the obvious choice for efficiency, I'd like to experiment with devolumizing the dump chamber and jacking the pressures, where the adjustable restriction might prove useful in testing. My gauge, which is a standard Ion gauge, registers the pressure at just about 100psi while shooting 300FPS.

http://www.youtube.com/watch?v=nPb96eXkYp4

EDIT ---Video of the actual prototype shooting

an94 · 10-11-2009, 05:55 AM

Wow thats cool as ****
Big

to you

QcXf · 10-11-2009, 12:39 PM

Thats sick. I want to see it shoot paint!

y0da900 · 10-11-2009, 12:42 PM

Quote:

Originally Posted by QcXf

Thats sick. I want to see it shoot paint!

I'm on the way into my basement in about 5 minutes to make a rail system for it so I can use a UTB and MAC 33 solenoid valve with a different grip frame, I'll have a video of it shooting paint in the next few days, the only one I have is an old dry firing video.

Nightmare Incarnate · 10-11-2009, 02:19 PM

That's really cool! about how many shots could you get out of a 20 oz before?

y0da900 · 10-11-2009, 03:18 PM

Quote:

Originally Posted by Nightmare Incarnate

That's really cool! about how many shots could you get out of a 20 oz before?

Not entirely sure as I bought the Ion "broken" for use in this project. The manual says ~800 stock, but that seems really low.

pbjunkiee · 10-11-2009, 04:47 PM

om nom nom

Charger · 10-12-2009, 01:52 AM

yoda.. you are the true master..

**Lurker27** · 10-12-2009, 02:56 AM

Awesome!

kingsmurf · 10-12-2009, 09:50 AM

Leafy · 10-12-2009, 11:46 AM

and that translates to how many shots off of a 68/45?

FMprime · 10-12-2009, 03:36 PM

Cool design! It reminds me of thorpedo's plunger prototype: http://attila.sdsu.edu/~thorp/Plunger.htm
I like how you just used the ion for cheap parts instead of making a whole prototype.

Is the bolt biased rearward with constant pressure? What's the lowest pressure the dump chamber reaches during firing?

It looks like you could add some holes further forward in the powertube to increase bolt cycle speed, similar how the invert mini bolt has a restricted flow path and a increased flow path once the bolt is forward a bit. The holes might also help the bolt open faster.

y0da900 · 10-12-2009, 08:35 PM

It does have some similarities to Thorp's plunger. One of my entries in the FASOR design contest was closer though, both of which are quite similar to the Assault 80.

I'm not sure what that translates to in a 68/45 other than a lot. Once I get my rail system set up so I can use a different frame, UTB, and MAC 33, I'll try to get some HPA testing as well as firing videos done. But I only have a 72/45, and don't have a ready source for a full fill, so it will take some interpolation and possibly sending it to someone for testing.

The bolt is biased rearwards with constant pressure, yes. Earlier generations that I never built (back to mid 2004) had the firing valve acting as a 3-way valve that cycled the bolt after firing, this is way way easier. Adding holes further into the power tube won't accomplish much as the holes at the back of the power tube between the bolt and the dump chamber are already larger than the restriction at the back of the can inside the donut.

Not sure how low the chamber goes during the firing cycle, that depends entirely on the dwell that the board is set to. I can set it as low as a stock Ion board can go and it doesn't seem to alter the velocity any, which could mean one of a few different things. It opens quickly enough that the lowest setting is adequate to vent the chamber of useful energy, or that my board is broken and is stuck at a higher dwell.

Leafy · 10-12-2009, 08:37 PM

Quote:

Originally Posted by y0da900

It opens quickly enough that the lowest setting is adequate to vent the chamber of useful energy, or that my board is broken and is stuck at a higher dwell.

might be time to take an interwebz trip to scenario dreams.

y0da900 · 10-12-2009, 09:02 PM

Quote:

Originally Posted by Leafy

might be time to take an interwebz trip to scenario dreams.

I already have a UTB and MAC33 waiting for it, just waiting to finish a rail/frame adapter to use them.

Leafy · 10-12-2009, 09:06 PM

Quote:

Originally Posted by y0da900

I already have a UTB and MAC33 waiting for it, just waiting to finish a rail/frame adapter to use them.

my reading skills fail.

FMprime · 10-13-2009, 02:11 AM

How long does the bolt open for loading a paintball? it seems like it might require a force feed hopper to avoid chops.

y0da900 · 10-13-2009, 04:22 PM

Not sure how long it does, and with an Ion board it does require a forcefeed loader. Part of the reason I'm using a UTB is so I can use the closed bolt eye logic for it.

Vaxer boy · 10-13-2009, 07:04 PM

nice work

I wanted to build some thing like that for my ion but I just couldn’t figure it out, then I lost my cad system because my pc crashed

sickion06 · 10-13-2009, 10:07 PM

altho i didn't understand much of the technical stuff being explained, it looks like this is going to be very cool and super efficient. patent this bad boy ha

Thorpydo · 10-13-2009, 11:21 PM

Very cool. I also like how you've modified an existing gun instead of build from scratch. I've done the same thing with the plunger design in a DM.

Honestly though, this design reminds me more of the legion shocker than it does the plunger. You've got a spool riding in a static bore, not the bolt's bore - main difference from the legion I see is the spool moves forward to open the valve, instead of rearward, correct?