CBHV: Masterclass entry

[Gun Freak]

This thing is amazing. Another fine creation, sir.

[warhead052]

Quick question, was this possibly based off of this? It seems like it would work, after all, it is kind of the same thing right?

[Moonbogg]

I just want to see it shoot something. Its great but I am dying to see it work.

[Brian the brain]

Quick question, was this possibly based off of this? It seems like it would work, after all, it is kind of the same thing right?

Exactly.

The valve works just like that.
All this time I had been thinking about incorperating the design in a compact way.

I just want to see it shoot something. Its great but I am dying to see it work.

Patience my friend
I guess you're not the buildlog type huh?
Hahaha.
The " perfect" steel ballbearings I have seem to get stuck in the aluminium barrel now the temperature has droppped ( significantly).

I might have to order some 10.9 mm lead balls.
Found them online locally.

I might decide to sand the inside of the barrel though.
Cheaper.
This entire gun already cost me...10 euro.

[warhead052]

Quick question, was this possibly based off of this? It seems like it would work, after all, it is kind of the same thing right?

Exactly.

The valve works just like that.
All this time I had been thinking about incorperating the design in a compact way.

Ok. Makes sense now.

[Brian the brain]

Hmm..
The bb's vary in size.

There's your problem.


I made the magazine and attached it.Right now it's slightly adjustable.

A tubular mag with a slot cut out now runs through a block wich is
securely fixed. I can reposition the tube along it's length to align with the breech
( by tapping it with a hammer!)

I'll fix it in place with a weld once I figure out wich bb's I can use.
Some feed great, others jam.

I'd like to keep the feed/breech hole this size exactly, so I will be unable to feed a bb that will get stuck in the barrel.

The difference is quite small.
Those that jam during feeding do make it through the barrel, just a tighter fit.
Those that just don't fit the breechhole will get stuck in the barrel.

So...tolerances are small..

Will sort out the bb;s and weld the mag in the exact position needed for smooth feeding and then it's time for multiple shots on vid.

I did get the opportunity to fire 2 in a row.Number three was slightly bigger and jammed.
But those two shots were very cool.
Clack-clack Bang! Clack-clack Bang!
Made a pocket out of a blanket to catch the bb's but the bb's went through..

[Brian the brain]

Update!
After the valve's O-ring had failed ( cheap @$$ quality btw) I had to take the entire gun apart.

But.....I put it back together and more...
The bottom picture was made for a certain somebody...


[youtube][/youtube]

[jackssmirkingrevenge]

Sometimes I wonder if my campaign against feet in photos was misguided. I really hadn't thought it through

Regardless, coming on nicely

[JDP12]

Looks awesome! question thats been bothering me.. How do you work out the spring power of the hammer valve and actual hammer? because it seems that the actual hammer spring would have to be more powerful in order to actual work the hammer valve, but then the problem is that it would seem the valve won't be able to reseat itself against the hammer?

call me retarded but please answer the question haha.

[Skywalker]

@JDP12:
Easy - the spring can be made so that there's no force on the hammer by the time it reaches the valve stem -- the momentum of the hammer then does the job of opening the valve.

@Brian: Freaking awesome gun, as usual! Can't wait to see it when you get through putting the furniture on it.

[JDP12]

Duh. I'm retarded. Another question- do you determine optimal hammer mass just through trial and error? Or do you have a general formula or method of determining it?

[Brian the brain]

This hammer is the result of trial and error.
I welded on two stubs for the mechanism and a nut on the axle.
It works just like Skywalker said.

But...the result of all this -figuring it out as I go along- means the hammer is fairly ugly.
I plan to use this one to make a new one, now I know where everything goes.I hope to make a brass one from a single piece...

But that is just to make it look better.
I'll take my time to replace or fix every part that bothers me untill it looks pleasing to me.

I have shaped and reshaped the basically all of the springs ( leafspring too) untill it worked just the way I wanted.

The lever and hammer both need to go.
They are quite literally prototypes.

I am quite pleased with the locking mechanism on the lever though.
There is a spring between the lever and the cocking-rod.

This pushes the rod outwards as the lever is at " rest" as the brass nut ( first thing I focus on in the vid when I pull the lever) slides into a shallow part of the cockingrod.
It locks it in position.
A very simple, compact and almost invisible solution.

Too bad the vid doesn't show it working due to the bad lighting

I just checked the gun...I usually go out to smoke and end up in my workshop...and I could still cycle and fire the gun...3 times....I hadn't touched it since last night..while after the vid I had done one more shot...So I guess it seals up nicely!!

I had only given it 31 ( why 31?? ..don't know..) pumps.

[JDP12]

Ah gotcha cool. Have you given any thought to dieseling it?

[Brian the brain]

No..not this time.
I haven't been able to duplicate my earlier results...

I have been pondering the thought of converting this thing to CO2 12 grams ( easy to do ) wich will give me some pretty powerful shots...and more importantly, less overall length and a LOT less weight in the front...

With the new heavier and wider lever I got planned that means I can attempt Terminator II style reloading...wich would be awsome.
Mine would be shorter, almost pistol-like...hmm
I just love shorty shotguns...
I'd even have higher shot capacity than the real thing and still have all of the gadgets on it...

I would mind paying for pressure though...



And what to do with that nice pump...??
How about a selfcontained piston hybrid all housed in seamless pipe, just a barrel running over it.
Fuelpump connected to the airpump?
Maybe...
I'll need help figuring out the metering though..

First I'll go all out on this one and create some art!


Made the top cover..I'll do more work on it later so this is not the endproduct.I'll engrave it and sand some off the sides to make it follow the frame.

The soot trick worked.
Not exactly the shotgun in the vid but I managed to shape it quite well intill it could be fixed in place with a single screw.
It doesn't slide or tilt in any way.

Too bad I had rounded off the steel frame before...else I could have made that seam much smaller...

[wyz2285]

wow, it needs some polishing, but awesome anyway
can´t wait to see it finished