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Posted: Mon Apr 16, 2012 8:31 pm
by Gun Freak
Roughly 100 psi per mix, no? :)

Contrary to popular belief, I'm quite well educated on hybrids, thanks :wink:
Though, I think GunFreak is wrong in this case and that the compression fitting could be used relatively safely at higher mixes than 5x
In the definitely possible case in which LnL has a better quality fitting than the kind I've seen, I wouldn't disagree with you.

Posted: Mon Apr 16, 2012 8:31 pm
by Lockednloaded
I think he was talking about my union EDIT:sniped, he was talking about my union. The parts may not be the most sturdy, but the union doesn't take all of the pressure a chamber does due to the fact that it's just holding the disk. Regardless, high-mix testing will be done at a distance

Posted: Mon Apr 16, 2012 8:32 pm
by MrCrowley
Gun Freak wrote:In the definitely possible case in which LnL has a better quality fitting than the kind I've seen, I wouldn't disagree with you.
I thought you were talking about JSR's fitting :P

Posted: Mon Apr 16, 2012 8:35 pm
by Gun Freak
Fair point LnL.

Crowley, wrong again :lol:

Posted: Mon Apr 16, 2012 9:03 pm
by MrCrowley
Gun Freak wrote:Crowley, wrong again :lol:
What else did I get wrong? :shock:

Posted: Mon Apr 16, 2012 10:08 pm
by Gun Freak
Mr Crowley wrote:Hybrids are better than pneumatics
^Wrong.

Posted: Wed Apr 25, 2012 9:10 pm
by mark.f
ITWOST: Finished my last lab for a physics class I took already (but didn't take the lab obviously :lol: ). Pretty interesting. Involved using numerical integration for modeling a projectile experiencing quadratic air drag.

I re-did the excel spreadsheet my group worked on and figured I'd post it here for anybody who wants to play around with it. Really not all that advanced math but I know a few people here who would like to learn.

In case you didn't recognize it, the default is a golfball launched at ~600 fps at 15 degrees. :wink:

Posted: Wed Apr 25, 2012 9:26 pm
by Lockednloaded
I've done it a couple times in this thread, but I was wondering if this was really the right place to post pictures of cannons that aren't really worth showcasing in thier own topic, but could spark some interest

Posted: Wed Apr 25, 2012 9:26 pm
by MrCrowley
Yeah go for it, I'd be interested in seeing some side-project cannons.

Posted: Wed Apr 25, 2012 9:47 pm
by Lockednloaded
Ok, these are two side projects that have kept my sane during the failures in my major builds :lol:

First, the "stubby" breech loaded, high pressure tennis ball gun

Image

Image


And Second, the "I'll eventually take some time to make it semi-auto" paintball gun with a BV breech

Image

Posted: Wed Apr 25, 2012 10:02 pm
by MrCrowley
I like the TB gun, how well does it perform? I put my TB barrel on a 3/4" QEV with a 1.25" chamber and it performed okay at 300PSI but no where near as well as my 2" sprinkler valve at 100PSI.

Posted: Wed Apr 25, 2012 10:20 pm
by Lockednloaded
Well, as far as performance, I really have no means of measuring it. It's typically used like a mortar to launch the balls either straight up, or way into the distance. However, despite the very leaky breech and tiny chamber, there's some power for it's size at 400 psi, but I've yet to take it to 600

Posted: Thu Apr 26, 2012 6:07 am
by mark.f
Neat little plinkers lnl. Wish I had an abundance of spare parts lying around at the moment to do the same.
Lockednloaded wrote:Well, as far as performance, I really have no means of measuring it.
Measure the hangtime and use the spreadsheet I posted. :lol:

Posted: Tue May 08, 2012 4:34 am
by MrCrowley
ITWOSTOD(the other day):

Underestimated the performance of one of my pneumatics, shot straight through a target when I thought there was no chance of complete penetration. I was really worried where the dart went but when editing the footage tonight I realised there was a distinct thud about a second after the shot indicating the dart is in the fence 20m behind the target*.

Funny thing is, I checked the fence from top to bottom just after the shot.
I think I'm even worse than DYI when it comes to lack of backstops :oops:


*The target was in my driveway but was just enough to the right that it was inline with a fence; so there was the possibility the projectile could have missed the fence if it deviated significantly going through the target.

Posted: Tue May 08, 2012 5:00 am
by jackssmirkingrevenge
photos/videos?

Also, dart? Have you joined the dark side when it comes to penetration :-O

It would be weird if a substantial high velocity projectile penetrated a target without a trace. Could it have struck the fence with minimal energy and just bounced off?