Aluminium bottles

[flamerz14]

I want to make an inline marble gun with a chamber of 2 aluminium bottles.Barrel will be 15mm(?) pvc. The bottles have a total volume of 1500cm2.

1.What is the effective barrell length?
2.Is just using epoxy to hold a mle adapter to the mouth of the bottle safe? (the botle's opening has too female many threads.I cant fit in a 18mm copper adapter.)
3.What presure can I take it up to?

[DYI]

A 424cm barrel would give you a 2:1 ratio, although that could be impractical...
The info you gave is to vague to give us any idea of safe working pressure.
The safety of holding it together with epoxy depends on the intended working pressure, which cannot be known until you give us more specs.

[flamerz14]

Lets see... I know of this high pressure epoxy(1500 psi). I intend to work it somewhere at its maximum pressure..wow.4m.thats long.What if I just used one bottle?(750cm2)

[iPaintball]

JB weld works great for that appllication, but not at such high pressures. If yuo intend to operate at such high pressures, what will you use to fill you chamber? What would you use as a valve?

[flamerz14]

nono epoxy rated to 1500 psi.I'm bringing it to only ard 200 psi..maybe a shock pump? idk i don't have a copressor..

[shud_b_rite]

Where do you get these aluminum barrels you speak of? And if this bottle is what I think it is, it should be safe to about the same pressures of a fire extinguisher (120-200) psi.

[mike1010]

Where do you get these aluminum barrels you speak of? And if this bottle is what I think it is, it should be safe to about the same pressures of a fire extinguisher (120-200) psi.

you must mean bottles

[jackssmirkingrevenge]

Some useful refernce, thebud gun on spudtech

[flamerz14]

Sadly my bottle's quite different...no taper justa botle with a ~18mm i.d. mouth..and about the effective barrel length?? i can put a 4m barrell on a sniper..

[jackssmirkingrevenge]

Any data on the wall thickness of the aluminum, what the bottle was originally used for? Some pictures would be helpful.

A 4 metre barrel is a bit much, it needs to be less than 2 metres to be managable.

[flamerz14]

wall thinkness is around 3mm on thickest.Bottle is drinkng bottle(duh) yea 4m is load much, any other C:B i should use?

[jackssmirkingrevenge]

3mm sounds like it will hold 100 psi safely, if it was originally made for carbonated drinks then it should be rated to at least 150 psi anyway.

For a 1.5 litre volume (and presumably 3/4" barrel if it's a marble gun) you can have the longest barrel you're comfortable with managing.

[flamerz14]

i'm sticking with one bottle (750ml) and thinking of using a C:B of 0.7:1 watcha think?

[spud yeti]

For lower chamber pressures, a bigger ratio is generally better as far as I know.