Hammer valve endeavour

wyz2285 · Sat Jan 21, 2012 9:01 am

can´t shot a 0.25g bb more than 50m, low noice, low speed, and low accuracy(that dependes, maybe bad accuracy for me but ok for you)

Gun Freak · Sat Jan 21, 2012 9:31 am

Damn, if it can't shoot an airsoft BB I don't think it'll shoot a pellet

But my valve is higher flow than yours... And I can make the hammer stronger to keep it open longer... If it still sucks, then this whole project would be a fail.

[youtube][/youtube]Woohoo

I'm gonna need a bigger gauge

[youtube][/youtube]

wyz2285 · Sat Jan 21, 2012 12:14 pm

Nice,high input doesn't help my fridge compressor through, with 50 psi input it doesn't go much more than 20 bar, but without input, it goes up to 1000

Your fridge compressor definitely has potential.
If you are going to shot pellets, you need 600 psi at least, but that also depends the barrel and the pellets weight. In my opinion pressure is more importante than valve opening time.

Gun Freak · Sat Jan 21, 2012 12:50 pm

I agree about the pressure vs opening time. I don't think I'd feel comfortable going over 500 psi... That's like an absolute max for me. What kind of pellets are we talking about here, .177 or .22? My barrel is .22 but I can take it back and use any other size... But I don't want to use airsoft because I intend to do some... Skyward damage... :duckie: lol

wyz2285 · Sat Jan 21, 2012 2:14 pm

.22 pellets, around 10g. For decent power/accuracy(+- 80m, 10cm grouping) I used a valve-less 500 psi gun.

Sat Jan 21, 2012 2:28 pm

You could build a stirrup pump..

If the hammervalve has a decent opening you'll be able to shoot pellets just fine.

Gun Freak · Sat Jan 21, 2012 2:38 pm

I don't need a stirrup pump now that I know my fridgy can do more than what I'm going to use.

Wyz, I'm not sure if I'll use .22s. They're expensive and will take more power than I can get with this gun. I think I want .177 caliber. But I can't get a good barrel for that, all the sizes are way off. I'd have to order something online to get good accuracy or use sabots or wadding, losing all accuracy.

I'd be opting for .177 BBs because it would do better in the smooth bore barrel.

What do you guys think?

wyz2285 · Sat Jan 21, 2012 2:51 pm

I was really unsure about what caliber I'm going to choose for my pcp, but when I found out that there is a Portuguese site that sells all kind of airsoft stuff, I quickly bought a rifled 6.03mm bb barrel, works both for bb and .22 pellets.

Gun Freak · Sat Jan 21, 2012 3:01 pm

.22 is 5.5mm though...

I think I'm just gonna buy the closest size brass I can find for .177 and use wadded BBs.

I calculated the seat diameter to be .2", which means at 500 psi the force needed to open it would be 16 pounds. At 400, it would be about 12. I think I need to make an inline striker because a rotating hammer delivering over 12 pounds of force would be hard to construct (for me, at least).

warhead052 · Sat Jan 21, 2012 3:17 pm

Gun Freak, you can use a drill bit, section of pipe, and an airsoft bb to expand the skirt of the pellet to fit an airsoft barrel. Not hard, JSR can confirm it.

Gun Freak · Sat Jan 21, 2012 3:27 pm

True, but that would destroy an authentic airsoft barrel. I think I could flare the skirt of a .177 to fit my available pipe size, thanks for reminding me of that idea. Now I just need to figure out how I will mount it and breech load it.

warhead052 · Sat Jan 21, 2012 3:29 pm

No prob. But if you use a airsoft barrel, then it also allows for skirmishing when you aren't shooting into the sky.

Gun Freak · Sat Jan 21, 2012 5:26 pm

I'm not going to skirmish with it. It will be too fiddly to load every shot and I'm trying to keep it really shiny (hence all the brass and copper) so I wouldn't want to mess it up skirmishing.

Gippeto · Sat Jan 21, 2012 11:47 pm

Wouldn't use bbs...or brass tubing.

If you're not going to use the .22 barrel you have, then go to the auto parts store with a pellet, and check out the replacement steel brake lines.

As I recall, there is one size that fits .177 rather well. Fairly sure it was 1/4" brake line.

BB's are LOUSY projectiles. A hop up may yield semi usable results if you insist on using them.

Diabolo pellets will drag stabilize, and if you can get a good fit in the bore, will be reasonably accurate from even a smooth bore.

You COULD order a Crosman .177 barrel for not much dough.

(Allan is a heck of a nice guy to deal with too!) Inexpensively available to you in lengths of 10", 14", and 24".

Think he'll cut and crown to custom length for a reasonable fee as well. Best to ask.

http://www.abairgun.com/ItemDisplay.php

Gun Freak · Sun Jan 22, 2012 6:41 pm

Thanks for the help Gip! I contacted him.

Some progress:

Inline striker housing and mount, made out of a single piece of copper

How do my joints look? Good enough for 400 psi?

Check valve modified quick connect to use with my fridgy. Took it up to 300 psi today, took about 10 seconds.

Hammer valve endeavour

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