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Posted: Thu Dec 31, 2009 2:30 am
by jackssmirkingrevenge
McCoytheGreater wrote:it should start to look less like PVC S&M, and more like a howitzer.
What a lovely quote

Posted: Fri Jan 01, 2010 2:46 am
by McCoytheLesser
IT WORKS!!! theGreater and I have brought in the new year with a bang, a very loud bang. ME 1-05H works beautifully and has a surprising amount of recoil with just a light projectile (an empty soup can). Can't wait to test a full weight projectile in the monster! A video is soon to follow this post.
Posted: Fri Jan 01, 2010 4:31 am
by McCoytheLesser
And here is the video of the cannon. Damage pics and videos to come soon.
[youtube][/youtube]
The high speed is low quality but it is really cool to see what the flame out of the barrel actually looks like.
Posted: Fri Jan 01, 2010 5:54 am
by McCoytheGreater
So the howitzer performs flawlessly. The surprising thing is that even with the weight of the gun it has a surprising amount of recoil. Even with light projectiles (soup cans, as mentioned above) there is still a full 12" of recoil travel. We'll be attaching the recoil springs and pneumatic return tomorrow, as well as performing a full scale test. The past nights tests were with empty soup cans. The next test will have 7oz.'s of Plaster of Paris in the can with a heavy projectile test to follow. We will also be measuring the muzzle velocity of the cannon with our high speed camera. Unfortunately all experimentation will cease after this week due to college resuming. Keep a watch, though, on the weekends. This has been a successful build for the time we have worked on it. A big thanks to all who have posted, made suggestions, and/or have warned us about this build.
Posted: Fri Jan 01, 2010 7:34 am
by jackssmirkingrevenge
Good stuff, some damage pics are definitely in order

Posted: Sat Jan 02, 2010 11:28 am
by McCoytheLesser
So yesterday theGreater and I shot Cerberus with a full scale projectile. The sound that came out of the cannon was deafening and we got some very valuable data from this test.
This is what we gathered.
Muzzle Velocity (approx.)- 650~670 FPS
Weight of Projectile- 7.2 Oz
Distance (approx) - 175 yards @ low trajectory (20~25 degrees)
This test was done with the meter pipe charged to 85 psi. and the chamber fan was left to run for 20 seconds.
By this afternoon I should have some damage pics posted along with the high speed shot of this test.
Posted: Sat Jan 02, 2010 1:30 pm
by RabidDuck
Looks VERY powerful for projectiles that size and weight. What are you planning to shoot at? Also are you using propane or MAPP? And how are you metering/measuring that? Can't wait to see the damage pics.
Posted: Sat Jan 02, 2010 8:00 pm
by McCoytheLesser
Here is a video of the cannon that has a full weight projectile (7oz). The high speed at the end is how we measured the muzzle velocity.
[youtube]
[/youtube]
I apologize, but I couldn't get around to making some damage pics or videos, there just wasn't anyway I could set up the cannon without theGreater not here ( too heavy), but theGreater will be back in tomorrow so we should be able to make some then.
Also are you using propane or MAPP? And how are you metering/measuring that?
We are using propane in the cannon (although MAPP would make for a nice boom

). We also have a proper metering pipe for the gun, but it just wasn't mounted to the cannon at that point of time.
Posted: Sun Jan 03, 2010 1:09 am
by jackssmirkingrevenge
That's a lot of recoil, good thing you have it properly braced

Posted: Sun Jan 03, 2010 1:31 am
by McCoytheGreater
Even with the bracing, we're going to replace the recoil springs with stouter ones and put bumpers at the end of the recoil rails to prevent a hard shock. get more springs for it. The ones we have definitely aren't giving the recoil reduction we'd hoped for. That being said, we definitely didn't foresee that amount of recoil in the designs. Luckily the gun itself probably weighs 80 lbs. Not necessarily light, but with the weight, the recoil probably isn't as bad as it could be with a lighter gun. Looking at muzzle brake designs. We're hoping to reduce the recoil by at least 25% Anyone have any suggestions for the construction? We're trying to keep it lightweight, yet effective.
A few pics to entertain.
Posted: Sun Jan 03, 2010 1:33 am
by jackssmirkingrevenge
You could raid your local junkyard for some gas springs...

Posted: Sun Jan 03, 2010 2:00 am
by McCoytheGreater
jackssmirkingrevenge wrote:You could raid your local junkyard for some gas springs...

I could do that. They make any where the work would be tensional and not compressional (I'm pretty sure I botched that phrasing)?
Posted: Sun Jan 03, 2010 2:21 am
by jackssmirkingrevenge
In vehicles they're typically under compression, I'm not sure if there are other devices that use them in a tensile fashion.
Posted: Sun Jan 03, 2010 3:07 am
by MRR
For the muzzle break you could simply use a tee that fits onto your barrel and drill a hole in the center of it. I saw that at least once here on spudfiles but I don't know how it performs.
Edit:
something like that

Posted: Sun Jan 03, 2010 4:29 am
by jackssmirkingrevenge
A muzzle brake would certainly help,
some suggestions.