Search found 36 matches

by Dig_Gil
Tue Aug 01, 2017 11:45 am
Forum: Pneumatic Cannons
Topic: Recoilless air cannon, possible?
Replies: 12
Views: 2103

Re: Recoilless air cannon, possible?

Maybe I'm late to this thread, but here's my two cents: A truly recoiless weapon must eject something at the rear. Having a contained counter-balance like a counterweight that moves inside the gun will not eliminate recoil, only delay (like the AEK models of AK rifle) or redirect it (as in the Kriss...
by Dig_Gil
Tue Aug 01, 2017 5:24 am
Forum: Pneumatic Cannons
Topic: Wacky Breechloading Launcher
Replies: 10
Views: 1585

Re: Wacky Breechloading Launcher

So, I had a someone PM me about this launcher, so I went to iterate over it again. This new version is more compact, can work with simpler lockwork (although in the drawing is simplified) and at last it has some means of manual extraction. The drawing doesn't feature the self-regulation feature beca...
by Dig_Gil
Thu Jul 20, 2017 12:15 pm
Forum: General How-To & Discussion
Topic: Partially loaded projectiles in coaxial guns.
Replies: 1
Views: 601

Partially loaded projectiles in coaxial guns.

I was thinking about new kind of loading mechanism which so happens that it doesn't completely fit the projectile inside the barrel. Like this (assume it's a simple cylinder): LaunchConcept.png Is this bad in anyway? Would the rush of air around the edges of the projectile build up pressure in front...
by Dig_Gil
Sun Nov 06, 2016 12:42 pm
Forum: Off-Topic Hobbies
Topic: Accidental Oscillator (Electronics)
Replies: 0
Views: 2499

Accidental Oscillator (Electronics)

I was playing around with LC tank oscillator ideas when accidentally an oscillator in Falstad's circuit simulator happened. I've tweaked the values of passive components to give the nicest waveform. It makes sort of a sawtooth wave with a double-bent back. I don't know how it really works and can't ...
by Dig_Gil
Sun Oct 30, 2016 7:35 am
Forum: Pneumatic Cannons
Topic: Wacky Breechloading Launcher
Replies: 10
Views: 1585

Re: Wacky Breechloading Launcher

So, I've been away, thinking about this concept further from time to time. Most difficult was to optimize it geometrically and come up with ways to regulate and trigger it in the correct sequence. I wonder what those guys posting about cartridged projectiles with in-built pressure chambers think of ...
by Dig_Gil
Fri Sep 16, 2016 5:52 pm
Forum: Pneumatic Cannons
Topic: Wacky Breechloading Launcher
Replies: 10
Views: 1585

Re: Wacky Breechloading Launcher

A choke is simply a narrow passage were air purposefully leaks in very slowly. There are industrial valves which do this, but it can be simply accomplished by forcing the air through tight passage, or a pinched tube.
by Dig_Gil
Fri Sep 16, 2016 9:50 am
Forum: Pneumatic Cannons
Topic: Wacky Breechloading Launcher
Replies: 10
Views: 1585

Re: Wacky Breechloading Launcher

Nice, I think this is a very elegant design. Curious to see how it will perform. Hooking up the trigger cocking to the regulator piston something I hadn't thought of before... I'm glad you like it. I think it was Leonardo daVinci who said that true sophistication is simplicity. I waste a lot of tim...
by Dig_Gil
Wed Sep 14, 2016 6:25 pm
Forum: Pneumatic Cannons
Topic: Wacky Breechloading Launcher
Replies: 10
Views: 1585

Wacky Breechloading Launcher

Developing from my last original post about coaxial launcher concerns, I've came up with an interesting concept I want to share. I'm not sure I will ever build anything practical out of it, but I'm interested to know your impressions. Maybe It's an idea that makes possible my pipe-dream of a full-au...
by Dig_Gil
Wed Sep 14, 2016 4:40 pm
Forum: Pneumatic Cannons
Topic: Why does no one make 12g co2 air guns/cannons?
Replies: 10
Views: 2220

Re: Why does no one make 12g co2 air guns/cannons?

Sure it can be done. I've considered an hybrid compressed air/CO2 design (where a CO2 cartridge is used as back up when main pressure dwindles) so to help regulation. It's highly convenient and (if your launcher isn't too large) powerful. But free atmospheric air is much cheaper and you're only requ...
by Dig_Gil
Tue Sep 13, 2016 6:44 pm
Forum: Pneumatic Cannons
Topic: Jöerg Sprave's Pneumatic Arrow Shooter
Replies: 3
Views: 1054

Re: Jöerg Sprave's Pneumatic Arrow Shooter

Maybe he's busy with his own forum nowadays...
by Dig_Gil
Tue Sep 13, 2016 2:06 pm
Forum: Pneumatic Cannons
Topic: Jöerg Sprave's Pneumatic Arrow Shooter
Replies: 3
Views: 1054

Jöerg Sprave's Pneumatic Arrow Shooter

NOTE: I wanted to call it a "crossbow" in the title, but I doubt that to be an acceptable term. If you don't know, Jöerg Sprave is an YouTuber who runs "The Slingshot Channel". He used to make videos of rubberband based contraptions that launch things into things, but lately he's been taking a likin...
by Dig_Gil
Tue Sep 13, 2016 1:51 pm
Forum: Pneumatic Cannons
Topic: Plausibility of coaxial cannon
Replies: 3
Views: 855

Re: Plausibility of coaxial cannon

Because it seems to be hard for people in this forum to answer these kinds of questions, I'll give you my two cents. Firstly let's make something clear: In a coaxial cannon you have a tube (where the projectile flies through) which is the barrel and another tube (enveloping the barrel, where air pre...
by Dig_Gil
Tue Sep 13, 2016 1:11 pm
Forum: Pneumatic Cannons
Topic: Interesting stuff from the internet...Huben K1
Replies: 2
Views: 1479

Re: Interesting stuff from the internet...Huben K1

Funny how I'm reading this right after making a thread asking about mechanically actuated launchers. In my thread I've put up a concept sketch where the chamber pressure is what's opening the valve and after pressure's gone a spring returns the piston to close the valve.
by Dig_Gil
Sun Sep 11, 2016 2:29 pm
Forum: Pneumatic Cannons
Topic: Considerations to have when building a Coaxial Piston Cannon
Replies: 4
Views: 1088

Re: Considerations to have when building a Coaxial Piston Ca

I imagine you could use a rotating bolt/piston like assault rifles use. It's a very tough and tried mechanism like in the picture attached. (Green things are airtight seals) MechaCoAx_concept1.png A sort of operating rod or "bolt carrier" would be used to unlock the piston, thus opening the valve by...
by Dig_Gil
Sun Sep 11, 2016 6:39 am
Forum: Pneumatic Cannons
Topic: Considerations to have when building a Coaxial Piston Cannon
Replies: 4
Views: 1088

Considerations to have when building a Coaxial Piston Cannon

I'm thinking about working on a Coax style launcher, obviously, but I wonder about what affects the efficiency of this kind of launchers. I've visited the spudwiki about the subject, but seems incomplete and too verbose. Nonetheless, the wiki mentions about the barrel-to-chamber ratio. Given there i...