SpudFiles

jook13 wrote:I think I will make one of dem dang ole nail darts. What would be a good penetration test? I think I could get a hold of a car door. I just dont think plywood would cut it.

Car door works then, you could compare it to pistols, rifles and shotguns

I plan to redo the pilot valve with a 2 inch splinkler as there is sometimes a delay after actuating it. Pulling the safety ball valve the same time as the sprinkler helps a lot.

Made in China then I would look to reducing your pilot volume too, it looks like there is some room for improvement.

Rag wrote:Oh dear, not that again.

Sorry, too good not to mention good luck with your latest, looking forward to seeing what you can come up with

This thin is amazing!! I love it

Great Caesar's ghost! That is a beast.

Can we get some more details about the piston?

Leave Harry alone! 8)

Impressive "little" cannon you've built there!

Among other projects, I have a 2" all metal cannon in the works, wich will be run at around 350-400 psi...

I'm a bit worried that is not gonna beat yours now...

The reason you have such a delay in firing is because the piston is almost the same diameter as the port. That means you have to get a large pressure difference between the front/back before the piston will start to move. Any leaks around it will slow opening time very noticeably.

A 2" pilot valve should work as a "brute force" approach, but a floating oring piston should help with the current setup.

What about using another piston valve to pilot this thing?

jackssmirkingrevenge wrote:Sorry, too good not to mention

I suppose it's my own fault. I should have never told you lot what I look like. :tongue3:

Good luck with your latest, looking forward to seeing what you can come up with

Well, to be honest... so am I to a certain extent!
I know exactly what I'm trying to build, but it's been such a long time since I last did this, so I'm more than a little out of practise.
For that reason and the fact I'm looking for the best end result, I'm taking things slowly and carefully.

Still, I have a reputation to keep, so I've got to manage something decent, ain't I?

Just saw this thing, and DAYUM! I was actually really suprised when I saw you holding that thing. This is probably a dumb question, but why do bigger cannons shoot farther? Is it just because the projectile is heavier? Velocity wouldn't be any faster than a smaller scale cannon would it?

Moonbogg wrote:This is probably a dumb question, but why do bigger cannons shoot farther?

That's not strictly true. An 81mm mortar fires a much larger round than a 50 cal rifle, but the latter has a longer range fired at 45 degrees.

When it comes to range, it's all a question of ballistic coefficient and muzzle velocity. The matter is discussed in some detail in this thread.

Naturally, bigger size is usually the result of a longer barrel or larger chamber, both of which would tend to give a better muzzle velocity and therefore more range.

WOW!

that damage is almost as amazing as THIS


(DO NOT REMEMBER WHOS THIS IS, ITS NOT MINE)

Very cool. I wish I had a beast like that...........