Search found 29 matches

by Xenophile
Sat Sep 02, 2023 4:09 pm
Forum: Pneumatic Cannons
Topic: DIY nerf rocket launcher
Replies: 1
Views: 50710

DIY nerf rocket launcher

Air cannon overview.jpg I love target shooting, and continue to enjoy the hobby, and I also enjoying engineering and building new things. For my latest build, I wanted something powerful that I could also safely use at a park. Multi-shot capability was a requirement as I didn’t want to have to repr...
by Xenophile
Mon Jan 11, 2021 12:44 pm
Forum: BB, Airsoft, and Pellet Guns
Topic: Agitator for a BBMG
Replies: 9
Views: 8591

Agitator for a BBMG

Hello all, Would there be any reason to add an "agitator"- a device to manually circulate the BBs in a BBMG? I'm thinking about an electric motor driven agitator similar to those found in some paintball hoppers. I believe in normal operation of a cloud style BBMG, the pressurized air provides the ag...
by Xenophile
Thu Dec 31, 2020 6:01 pm
Forum: BB, Airsoft, and Pellet Guns
Topic: Ammo feeding for a QEV/popoff cannon
Replies: 9
Views: 7698

Re: Ammo feeding for a QEV/popoff cannon

It appears to only shoot one bb per shot, but with its high ROF from the popoff valve, it's a little hard to tell. I'll probably disconnect the current barrel/magazine assembly from the current gun, and attach it to my reliable QEV semi-auto gun just to verify that the current ammo feeding mechanism...
by Xenophile
Thu Dec 31, 2020 4:19 pm
Forum: BB, Airsoft, and Pellet Guns
Topic: Ammo feeding for a QEV/popoff cannon
Replies: 9
Views: 7698

Re: Ammo feeding for a QEV/popoff cannon

There's no bolt currently, although I might mess around with adding one in the future. It seems to function fine without, though I'm probably negatively impacting performance. In the meantime, I'm still working on improving the magazine and its attachment to the gun. I'll keep you guys posted.
by Xenophile
Wed Dec 30, 2020 1:44 pm
Forum: BB, Airsoft, and Pellet Guns
Topic: Ammo feeding for a QEV/popoff cannon
Replies: 9
Views: 7698

Re: Ammo feeding for a QEV/popoff cannon

Thanks again, although I believe I've found a different solution. Crude magazine.jpg This is a crude magazine I've cobbled together with some brass pipe, compression springs, epoxy and heat shrink tubing. The capacity is about 50 .177 bbs. There's a large "L" shaped groove I cut to allow the followe...
by Xenophile
Mon Dec 28, 2020 4:34 pm
Forum: BB, Airsoft, and Pellet Guns
Topic: Ammo feeding for a QEV/popoff cannon
Replies: 9
Views: 7698

Re: Ammo feeding for a QEV/popoff cannon

Clever design! I like the idea of using air from the barrel to push the ammo down in the magazine. Does it make reloading more difficult though? Currently, I'm waiting on some epoxy to cure on a "follower" piece that I will be adding to the inside of some ~5mm metal pipe to make a spring loaded maga...
by Xenophile
Sun Dec 27, 2020 5:48 pm
Forum: BB, Airsoft, and Pellet Guns
Topic: Ammo feeding for a QEV/popoff cannon
Replies: 9
Views: 7698

Ammo feeding for a QEV/popoff cannon

Hello Spudfiles, I've been working on a cannon that uses a Quick Exhaust Valve (QEV) as my main valve and a 200 psi safety popoff valve to give me a fully automatic rate of fire. I'm using a 3 position 2 way (3/2) valve as my trigger, and I have an old crossman barrel in .177 caliber (4.5 mm) attach...
by Xenophile
Thu Nov 26, 2020 11:36 am
Forum: Pneumatic Cannons
Topic: Yet another QEV and 3/2 valve cannon
Replies: 5
Views: 5084

Re: Yet another QEV and 3/2 valve cannon

Thanks for the idea JSR! I continue to make more modifications and improvements to this thing. scoped.jpg For example, I've added a scope, and a proper laser sight (not shown, on the other side) for greater accuracy at longer ranges. snow with bolt action 2.jpg I've also added a proper bolt action/i...
by Xenophile
Thu Oct 15, 2020 5:46 pm
Forum: Pneumatic Cannons
Topic: Yet another QEV and 3/2 valve cannon
Replies: 5
Views: 5084

Re: Yet another QEV and 3/2 valve cannon

Thanks JSR, I'm glad you like it! I've completed a gravity fed magazine ( 10 shot capacity for .30 caliber shot) which is working fairly well, but I am having some issues with double feeding. Air gun overview .jpg I'm using a "detent" system with neodymium magnets to keep the shot in place, but this...
by Xenophile
Sat Sep 19, 2020 6:09 pm
Forum: Pneumatic Cannons
Topic: Yet another QEV and 3/2 valve cannon
Replies: 5
Views: 5084

Yet another QEV and 3/2 valve cannon

Overview of FS resized.jpg My latest creation. As the title suggests, I using a QEV and 3 position 2 way valve with a 300 psi input from a regulated HPA paintball tank. I have two different barrels, one for 3/8 inch (9.5 mm) steel shot and another for .30 caliber steel shot. The 3/8 inch barrel is ...
by Xenophile
Sun Jul 19, 2020 12:02 pm
Forum: Pneumatic Cannons
Topic: MJVO-3 venting air from the sides
Replies: 6
Views: 6892

Re: MJVO-3 venting air from the sides

Thank you for getting back to me. I appreciate all of your thoughts! I've independently tested my QEV using a slide valve, and it functions as expected; properly filling the secondary chamber and releasing air out the barrel. I even added more lubricant to the QEV to ensure the cylinder was properly...
by Xenophile
Fri Jul 17, 2020 5:36 pm
Forum: Pneumatic Cannons
Topic: MJVO-3 venting air from the sides
Replies: 6
Views: 6892

MJVO-3 venting air from the sides

Hello Spudfiles! I've been working on a new cannon which uses a QEV piloted by a Clippard MJVO-3. Unfortunately during my initial pressure test at 100 psi, when I fired the cannon, air vented from the two holes on either side of the MJVO-3 instead of into the QEV and out the barrel as intended. The ...
by Xenophile
Sat Feb 01, 2014 2:09 pm
Forum: Pneumatic Cannons
Topic: The Goblin; a QEV paintball gun
Replies: 5
Views: 3491

Re: The Goblin; a QEV paintball gun

Believe it or not, the pipe I'm using as a barrel has an almost perfect seal with very little blow-by. I think its a threaded pipe for a sprinkler. I have not yet tested it on a full tank of CO2, but I should get around to it soon. Prototyping uses a lot of gas! I'm curious about how to include a bl...
by Xenophile
Fri Jan 31, 2014 7:07 pm
Forum: Pneumatic Cannons
Topic: The Goblin; a QEV paintball gun
Replies: 5
Views: 3491

The Goblin; a QEV paintball gun

photo (4).JPG Hello spudfiles. I have recently created perhaps my greatest pneumatic cannon to date! I call the beast "The Goblin". As far as the specifications go, I run the gun at around 90-120 psi using a Palmer regulated paintball CO2 tank. I'm using a standard QEV and slide valve set up to ena...
by Xenophile
Sun Jun 03, 2012 5:12 pm
Forum: Combustion Cannons
Topic: Having trouble getting a tennis ball mortar to shoot
Replies: 5
Views: 3011

Having trouble getting a tennis ball mortar to shoot

Hey guys. I have recently constructed a tennis ball mortar out of 3" diameter PVC pipe with two pringles cans lining the inside to act as baffles as detailed in the tennis ball mortar plans of the book "Backyard Ballistics". I use lighter fluid as my propellant an a piezoelectric lighter or long han...