Search found 79 matches
- Fri Jul 12, 2013 8:30 pm
- Forum: General How-To & Discussion
- Topic: About rifling an aluminum barrel.
- Replies: 5
- Views: 2278
- Thu Jun 27, 2013 7:37 pm
- Forum: Pneumatic Cannons
- Topic: QEV settings in GGDT?
- Replies: 2
- Views: 1215
- Thu Jun 27, 2013 2:32 am
- Forum: Pneumatic Cannons
- Topic: QEV settings in GGDT?
- Replies: 2
- Views: 1215
QEV settings in GGDT?
What should be entered for the settings for valve data in GGDT with a QEV like this one?
- Wed Jun 26, 2013 3:38 pm
- Forum: Pneumatic Cannons
- Topic: pneumatic locksmithing?
- Replies: 19
- Views: 5657
- Wed Jun 19, 2013 11:58 am
- Forum: Pneumatic Cannons
- Topic: Simple copper coax
- Replies: 11
- Views: 5117
- Mon Jun 17, 2013 10:59 am
- Forum: Pneumatic Cannons
- Topic: Simple copper coax
- Replies: 11
- Views: 5117
250psi is the highest my pump will go and most shots are around 220. When I take the gun apart I'll take a picture of the piston and weigh it. It's solid delrin, about 1.5" long and 1.2" in diameter. The piston travels about 0.3"-0.5". I'm thinking the power issue comes from the small chamber. I hav...
- Sat Jun 15, 2013 4:40 pm
- Forum: Pneumatic Cannons
- Topic: Simple copper coax
- Replies: 11
- Views: 5117
The piston has a great seal, but I kinda like the power behind a one-shot system, despite it being a long process to fire. I was thinking of carrying around a paintball tank and having a regulator supply the gun with air, which will remove all the time spent filling it with a bike pump. I haven't fi...
- Sat Jun 15, 2013 3:41 pm
- Forum: Pneumatic Cannons
- Topic: Simple copper coax
- Replies: 11
- Views: 5117
- Sat Jun 15, 2013 3:36 pm
- Forum: Pneumatic Cannons
- Topic: Simple copper coax
- Replies: 11
- Views: 5117
- Sat Jun 15, 2013 2:39 pm
- Forum: Pneumatic Cannons
- Topic: Simple copper coax
- Replies: 11
- Views: 5117
Simple copper coax
It's a fairly light gun, compared to the barrel sealer I have (in the background of the second pic). It's not as powerful though, so it's just for backyard plinking. Lead balls fly a little too slowly with this gun for my liking, so I'm also looking for some lighter ammo that I could use, and maybe ...
- Thu Feb 14, 2013 3:42 pm
- Forum: Pneumatic Cannons
- Topic: GGDT isn't showing the same velocities I get with a chrono
- Replies: 9
- Views: 3108
^Nice video I redid the shot with the muzzle 3 feet from the chrono's first sensor and hit 1102 fps. Learned my lesson here. Based on this shot and another with a lead ball, my flow coefficient is somewhere between 30-50%. What are other people using in GGDT for the flow coefficient of their barrel ...
- Wed Feb 13, 2013 6:56 pm
- Forum: Pneumatic Cannons
- Topic: GGDT isn't showing the same velocities I get with a chrono
- Replies: 9
- Views: 3108
- Wed Feb 13, 2013 5:46 pm
- Forum: Pneumatic Cannons
- Topic: GGDT isn't showing the same velocities I get with a chrono
- Replies: 9
- Views: 3108
- Wed Feb 13, 2013 5:32 pm
- Forum: Pneumatic Cannons
- Topic: GGDT isn't showing the same velocities I get with a chrono
- Replies: 9
- Views: 3108
GGDT isn't showing the same velocities I get with a chrono
Is there something I'm doing wrong here or did the chrono somehow misread the shot? Everything I entered in the GGDT matches up fairly well with the conditions I had, and everything was measured with digital calipers and a digital scale. I couldn't figure out the exact chamber volume or pilot volume...
- Fri Jan 11, 2013 12:19 am
- Forum: Pneumatic Cannons
- Topic: Experimenting with a REAL DIY vortex cannon!
- Replies: 47
- Views: 26325
This is so untrue; you can definitely send a projectile off faster than the speed of sound of the gas you are using. It really just depends on how much energy you put into the gas and how well you can use that energy. If I made a burst disk cannon with the disk's rupture pressure around 10,000 psi, ...