GB Semi

[Brian the brain]

The bolt wich loads the ammo should not open before the barrel is closed off entirely. Give it more travel to prevent the blow-out thing.
In other words make it longer, so the barrel is blocked off long before it starts to vent.If it still leaks into the mag, you need to check those O-rings...
Use grooves to keep them in place.
In theory that should work.
Too bad it's very hard to do in metal!!!

I would really appreciate if you would build "my"version of the valve to see how it would turn out.

So little time, so much to do!!

[Brian the brain]

That video ( just watched it) scared the crap out of me hahaha!!!

Never seen anything like that!
Is that your nabour in the back??He looks like;"what the F@&K is that guy doing?!?!?!"

Love it! Way cooler than my Marble MG.[/list]

[Brian the brain]

That video ( just watched it) scared the crap out of me hahaha!!!

Never seen anything like that!
Is that your nabour in the back??He looks like;"what the F@&K is that guy doing?!?!?!" ( or maybe he's about to tell your leafblower is foulty??)

Love it! Way cooler than my Marble MG.[/list]

[clide]

Cap and spring would probably work for a fairly small clip, but I still wouldn't be happy with it because of the limited size and I would just feel wrong abandoning the original goals of being able to use a hopper.

That's my dad that you see in a few of the clips.

I actually had to shorten the travel to stop the o-ring blowout problem (which is fixed now). The bolt started to hack into the rubber stopper that I had and was allowing the bolt to go too far. The bolt does allow air to flow through pretty much right when it closes off the loading port. When I put the loading mechanism on my test setup (to allows easier disassembly and tweaking) it works fine without letting any air out, but something about the rapid fire is affecting it I just need to figure out what.

Anyway, thanks again to all those who have left comments and given competition votes.

[Velocity]

Any updates on this gun? I am really interested in it, and can't wait to see how it fires when all of the bugs are worked out!

[clide]

Nope, haven't worked on it since the last video. I've been busy, and there are a few things that have taken priority, but I am still planning on tweaking it more eventually.

[Pete Zaria]

@Clide,
I just wanted to let you know, you have my vote (and apparently that of 29 others...) because this is one of the most innovative, well-designed, throughly-researched, most functional cannons I've seen in a long time. You may have borrowed small parts of your design from other known guns, but this is pretty damn unique.

I hope you don't stop here. Keep evolving the design and keep us updated.

Amazing job. Enjoy the cash prize....

Peace,
Pete Zaria.

[Billy Bob]

Congratulation 8)

Why didnt anybody wrote something ? He wins or not

I hope you will use the 100 to buy spudgun equipment

[clide]

Thanks Pete, Billy and everyone who voted for the GB Semi or have given feedback

Thanks to PCGUY for holding the great contest, and to all the competitors who made it fun.

[mtronic]

sweeeeeeeeeeet.

Perhaps to stop the balls from flying out off the loading port you could adapt like a threaded cap with say a big soft spring fixed on the inside of the cap. similar concept to a magazine?that way it would keep a consatnt downward pressure on the balls and be able to take some of the upward impact that we saw in the vid? Im sure if you can build such a sweet cannon you would have no probs adapting such an idea. But hey what would I know Im only a nOoB

perhaps i should have read ALL the post....my bad

[Rudesill Ballistics]

I figured an autoloader/automatic would require two separate mechanisms to reload and valve the air supply.

Great!

[mate68]

wow that´s amazing but i was looking into the valve system an the piston thing an i was wandering, does the air shoot the ball or the piston??

because i am planning to build mi first cannon and and i kinda need some advice

[clide]

wow that´s amazing but i was looking into the valve system an the piston thing an i was wandering, does the air shoot the ball or the piston??

because i am planning to build mi first cannon and and i kinda need some advice

I suspect you mean the loading mechanism by "piston thing".

Air does indeed shoot the ball. The loading mechanism simply moves forward so the loading port is blocked off and air won't shoot all the ammo in the magazine out. The animation is cut off at the very back of the barrel, and a big chunk of the middle of the chamber is left off so that it will fit in a reasonably sized box. Now that I look at it I can see how that could be confusing.

Good luck on your first cannon. I would suggest starting with something simple like a sprinkler valve gun or maybe a coaxial piston valve if you want to build your own valve.

[mate68]

thx for the info,


i have completed the presure tank for now and im moving forward to the vale and loading mechanism, im looking at some designs here on the forsm but they all look a little complex for my first build so im thinkink and planing to build a more simlpe one but that at the same time allows me to control the amunt of air that im going to use because i dont want all the air to go out whit one shot

[jackssmirkingrevenge]

a more simlpe one but that at the same time allows me to control the amunt of air that im going to use because i dont want all the air to go out whit one shot

What size of projectile are you planning to use? A large multishot will require a massive reservoir or a nearby compressor, your best bet is 0.177" BB or 6mm airsoft caliber - and you can't get much simpler than this:



Just a barrel hooked up to a blowgun, and the power isn't bad either.