I have an air cannon with interchangeable barrels. so far, I have a 1 1/2" barrel and 1" barrel. I am trying to get paracord in a tree for my ham radio antennas. I have seen the suggestion of an arborist's weight bag. Does anyone know any good alternatives? Tennis balls were the go to at least over...

jackssmirkingrevenge wrote: ↑

Thu Nov 16, 2023 1:10 pm

That's a hell of a BB gun.

Reliability stacks, the more parts, the more often the machine stops. Theoretically, a spool valve like you built with one moving part should be very reliable. However, you probably need to look into how the seals on DCV's are done, O rings rarely like to move past porting, having the o-rings seal i...

He's still at it! Nice work as always.

jackssmirkingrevenge wrote: ↑

Thu Nov 09, 2023 12:26 pm

Here is what it looks like internally, if it seems a little unusual that's because it's actually part of another project that I will share at a later date:

Cryptic as always. Does it have to do with cartridges?

Interesting find, we definitely need some more test data on hybrids to improve the modelling others have done.

Any other stand out builds or ideas on here over the last 10years I’ve been absent? My holy grail would still be a large caliber cartridge ejecting semi auto. I should complete that QEV repeater build one day. There's been a lot of small and intricate hybrid builds especially by hectmarr. But ten y...

The 0.8:1 ratio comes from burntlatke's testing where chamber volume was held constant and barrel volume was changed, which effectively found the longest barrel length that could efficiently use a certain chamber size. Increasing chamber size up to a certain point will just lose efficiency. You coul...

I'm obviously no expert but every time I heard our (now inactive) UK members talk about airguns they almost always mentioned muzzle energy restrictions.

So does it fire from an "open bolt" or closed? Like are the solenoid and solenoid valve energized simultaneously?
I would hazard a guess it has to do with your power supply and isolation between the solenoids but a little more detail could help.
Also that sounds awesome, hope you share soon!

Like pennywise said, depends.
I don't think anybody's actually measured it but using HGDT usually shows higher pressures in the barrel when modelling hybrids.

Obviously looks great! Speaking to the silencer, are you planning to use the extra length of lower tube for expansion volume? If you're beating your head against the wall trying to figure out how to rifle the barrel, and you have a 3d printer, you can take a look at electrochemical rifling . Good jo...

It sounds like you just need a venting regulator if I'm reading correctly.

jackssmirkingrevenge wrote: ↑

Mon Mar 13, 2023 9:49 am

MP5

Now I guess you need Rit-job STABO and ALICE gear, a flight deck helmet, and a balaclava.

That's cool but would it be better than something like this? I was actually about to pick up a tank and pump for a future project.

Same thing can happen easier with oxygen tanks, but I probably don't have to sit down and do the chemistry to see how much of a few grams of petroleum grease can do in a sealed oxygen rich environment, even if it is an HPA tank.