Almost done!

[qwerty]

Yay!, you will probably see quite a difference.

[Jack_Hogg]

I am going to make the piston hollow again, but this time the hole will be filled with blue foam, so that it is even lighter. I made a quick scetch in MS Paint. Please tell me if this is a good design or not.

[qwerty]

Yep that seems fine, although you probably could make it abit shorter to reduce weight but it dosent really matter.

[Brian the brain]

Why not drill it out from the other side??
And add volume to the chamberside in stead of pilot side.

Just leave a small core around the bolt ( 1 mm thick?) and lathe out the rest.

Oh...you could also put a spring behind the piston and use/make a oneway valve so you can fill chamber-side..
And get rid of the QD at the handle all together...

[Jack_Hogg]

I have to see if I have a chisel for cutting it out like you said. But I am a bit concerned it won't be strong, I think the core could snap/ break during firing. And about the spring behind the piston thing.. Does it hurt performance? Still I think the simplest and strongest design is mine But then still, I heard about the foam can collapse or damage during firing or filling. What should I do? You think the blue foam is strong enough? (Corporal with this post )

- Thanks

EDIT: About to get the ballvalve looser I asked earlier on page 1.. It's nice and loose. I have opened and closed the ballvalve by hand like hundreds of times so it get's hot then just keep on going.. It's nice and loose, but not too loose.. Just about right, so you don't mess your aim allot.

[spudtyrrant]

you have worked with nylon right jack?
it is tough stuff, I'm sure it could hold its own without a bumper, so with a good one it should do just fine, nylon is pretty light so i would suggest just drilling out a small amount or alternatively making a hammer piston if you really ant to reduce weight

[Jack_Hogg]

Well, the piston is done now.. It was actually done last monday, but my phone cable is kinda.. not.. working.. Ah well... It preforms very good now! Very nice loud bang and big recoil are welcome 8)

Should I make a folding stock?

Yes.
No.

[qwerty]

Should I make a folding stock?

No. I think it looks fine how it is.

[psycix]

Well, the piston is done now..

Piiics!

Very nice loud bang and big recoil are welcome

In general, neighbors DISAGREE to the first.

At first I liked a loud bang too. Until I had to put ear protection on to shoot.
At some point KA-BOOM becomes KA-BEEeeeeeeep....

[Jack_Hogg]

My cable is working now!

Here are the pictures:






It's just exact the same as the design, except for the steel washer and the blue foam, will add it later offcourse... The surface of the piston is very smooth. No scratches, and it fit's like a glove! I didn't make a EQ hole or channel in my piston. I just tested, and it fills just fine. About just the right flow.

[rikukiakuchiki777]

Very nice, but make a video!!!

[jackssmirkingrevenge]

Nice piston

I think a sliding stock like the one on the M3 would be more appropriate for the style, or a folding over stock like on the SPAS-12

[Jack_Hogg]

Nice piston

I think a sliding stock like the one on the M3 would be more appropriate for the style, or a folding over stock like on the SPAS-12

You and I both have the same thoughts
I have thought of making a folding stock like the one on the SPAS-12,
but then I would not have much grip left when unfolded. I have made some drawings on paper, and I also thought of making a sliding stock like the one you showed. But then I had another issue, because It couldn't slide in the gun because the ballvalve is in the way.. So think and think again.. The romanian AK side style folding stock would be the only option, and would not be hard to make.. But then again.. Maybe I'll try to design a SPAS-12 style folding stock, so I have the looks, the grip, and more compfortable to hold. But I am not sure.. So you guys may choose to add stock or no stock

[jackssmirkingrevenge]

There is an easy and not too expensive option, but it goes against the homebuilder's spirit...

[psycix]

Piston looks good!

Not sure about the stock. Do you want to aim accurately?
I'd say just try to find something that looks good.