mini hammer valve

[psycix]

he'd need a hammer about 50 times heavier.

Just for the heck of it, he should try it!

[JDP12]

Tungsten carbide anyone?

I believe that is pretty heavy!

haha

[jackssmirkingrevenge]

Just for the heck of it, he should try it!

I did actually, clamping lead weights to the end of the bolt and it does slow down the rate of fire but nowhere near what I wanted. At a point it just stops cycling.

[psycix]

Okay. Then there are two other options to slow it down:
-A larger scale (marbles?)
-Add a sear where the hammer gets caught, and then release it again by pulling the trigger (semi-auto)

[jackssmirkingrevenge]

Semi auto would be pointless, as you might recall I'm already the proud owner of a 30 ft/lb semi-auto FX Monsoon so it's *dakka dakka dakka* or nothing

I'm inclined to built a smaller version of the pop-off valve (maybe having it in line with the barrel so the piston movement also operates a barrel sleeve to reload ammunition) - still sticking with 3mm BBs because I've been very impressed with the sort of penetration they give when fired at high pressure.

[JDP12]

Hmm... couple ideas/questions

1) WHy did you make the hammer housing so long?

2) How did you determine the best spring? Did you just experiment til you found that it was allowing air out the outlet?

3) How are you gonna implement a trigger?

4) Now an idea. In order to slow down the ROF... because it seems almost constant right now I cannot believe how fast it is. What you could do is enlarge the hammer spring housing tube. Step it up alot- that should allow it to slow down I think because the air will be forced to push a larger hammer back, but the disadvantage may be that the air won't be able to.

Thanks, and just an opinion I had.

[jackssmirkingrevenge]

1) WHy did you make the hammer housing so long?

BEcause I wanted to have space to play with different springs

2) How did you determine the best spring? Did you just experiment til you found that it was allowing air out the outlet?

I started off with a spring that was just long enough to get the end of the hammer to touch the valve stem, then added progressively longer springs until I got it firing reliably

3) How are you gonna implement a trigger?

In this case I won't as it's not worth pursuing, but I outlined the details in the original concept were I to include a trigger.

4) In order to slow down the ROF... because it seems almost constant right now I cannot believe how fast it is. What you could do is enlarge the hammer spring housing tube. Step it up alot- that should allow it to slow down I think because the air will be forced to push a larger hammer back, but the disadvantage may be that the air won't be able to.

Do you mean enlarge the hammer diameter? I think this would be counterproductive as it would increase dead space and severely reduce the power available at the breech end.

[Brian the brain]

Jack...everything changes when you put a barrel on it and fire projectiles.

The outcoming air will be held back for longer, while the barrel is filled up.
When the projectile leaves the barrel. all air will be released and the hammer will be allowed to hit the valve once more.


That is...providing air doesn't leak past the hammer like it does now.


So finetuning the valve, without the barrel, o-ring and ammo is pointless.

[JDP12]

hmm interesting. that actually makes sense.

I may have to try this with a marble caliber seeing as I already have a lot of marble caliber stuff.

[SEAKING9006]

I think BTB may be onto something. Actually hooking it up to an existing barrel with an actual round in it might give the valve the dwell time it needs to be effective. Only one way to find out...

[clide]

I second what BTB said. Adding ammo should change the valve dynamics quite a bit. It is a bit of a PITA to have to be firing ammo any time you want to tune your valve (less so with BBs compared to golfballs), but that is one of the joys that comes with auto valves. Most auto valves that I have seen are sensitive to the outlet pressure caused by ammo being present.

[Brian the brain]

I did my research on full auto you know.
This is basically an Autococker.Wich is very promising BTW.

I think this is the only way to true full auto.And the 3mm bb's are just a genius way of going about it.The main thing that put me off on my attemps, where the massive aircomsumption and the related problem of not being able of building that kind of a think portable.

No for the valve:


Tiny changes may result in mayor differences in ROF.

The O-ring could change everything.
Another issue is the travel of the ...hammer ..to the venthole.
The longer it has to travel, the lower the ROF will be, the harder it will be to strike the valve ( aircushion).

He is not finished experimenting for quite some time.

[JDP12]

BTB... I don't believe i'm understanding how important the o-ring is.

Why does it matter so much?

[jackssmirkingrevenge]

You guys make valid points but somehow I'm not convinced this is worth pursuing. I've been thinking of going back to the pop-off valve, maybe combined with a blowback bolt, something like this:

[psycix]

When air leaks past the hammer you lose pressure.
When there is an projectile, the pressure will need to be there much longer and thus the leaks become more significant.

JSR, dont throw it in the failbox yet! It should be able to work!