Wow. Impressive stuff. I'm not 100% sure what you mean about the lapping though. Shouldn't a cy200linder of pvc be pretty perfectly round anyway?

If the piston is moving through that thing just by gravity... And is airtight... Wow. Nice job.

how could I get my hands on one of these nice nylon thingies? Very creative. Some airguns use leather funnily enough.

His FAR is the reason I started doing this. My gun will be exactly the same, just a bb version.

If only they had 0.2 or better, 0.25... 0.12 is just too light for a medium-powered sniper...

Is it possible to get this stuff here? Is there any way to get it sent from overseas? I was thinking I could get someone to send bb's with a bunch of sewing beads, and a barrel with a model kite, so it looks like part of the model. Pretty desperate I know but what else can I do? Problem is I don't k...

Hey, thanks a lot for all the tips. My air chamber is actually a diameter of 3cm and a length of 15cm, I just calculated it would need to go 1.5cm to move the needed volume of air. I'm pretty sure I'll be using a spring with total compressio of 15cm, at 11N/centimeter, which would give me 165N at di...

ffs double post sorry, so you were saying that the bb doesn't start moving until the piston is close to the end of its needed distance? in that case, maybe I wouldn't need such a high piston acceleration... And I have no idea how I'm gonna find out my efficiency, so I guess a lot of this will be tri...

Ok guys I think I know what's going on. The volume of the barrel is 9.9cm cube. I calculated that if I want the bb to be at 650 fps at the end of it, it would need to accelerate at 57143 meters per second squared, giving it a total time in the barrel of 3.5ms. Now I know this is all theoretical, but...

What I was doing, which is pretty funny, was using pi times diameter squared not pi R squared. Lol. Anyway, I couldn't possibly buy and airsoft sniper in Aus, its all illegal. With my "proper" calculations, I got 0.27 cm cubed behind the bb before it fires, and a 2.36 cm chamber. This gives me a pre...

I'm making a spring-loaded sniper rifle. With 0.2 gram bb, I want 650 feet per second. (maybe I should use at least 0.3 gram?) I've got a chamber with a plunger pushing down it. The chamber is 4.23 cm cubed (it is 1cm steel pipe 3cm long) the space behind the bb is 1.41 cm cubed with the plunger all...

thanks a lot for the brakeline link man, you're a genius. It makes total sense. Does the 5/16 refer to the outside diameter? cos 5/16 icnh is almost 8mm- so is the inside diameter close to 6mm?
PS. Where did you get yours? a local auto parts place?

Hi, I'm in need of a 6mm airsoft barrel, like a proper one, but I can't get it in my country (Australia). I need to find a way to have a barrel shipped here. I was thinking I might try to find someone who would do it for me for some money. Kind of a desperate thing to do, I know, but hey, I got no m...

Thx for the link man. Its hard to find o-rings of the right size, and the right constitution to allow the bb to get through but give resistance. I was makin o-rings outta rubber bands, but I thought I could inject a layer of glue that sets as a rubbery solid and then drill a hole in. is there an onl...

So I cant get airsoft in this glorious land, and I cant afford lots of co2, so I'm trying to make one on the cheap. I dont have high expectations, just a spring design. Because I cant get real barrels, I have to take a different approach. Im using a bike pump driven by a spring to force air into a s...