SpudFiles

Well here's my second coaxial piston which KICKS THE 5HIT out of my last one and im quite impressed with.,this is the product of 4 hours work,Its made from brass/aluminum tubing. chamber/barrel .
The cap on the pilot side is a 5/8 brass cap with a 1/4'' threaded socket silver soldered on the end ,it took about an hour of fileing to get it looking this good.The other end is just a plane brass 5/8 cap with a hole drilled through the centre to grip the barrel.
the spacer is a larger piece of aluminium tubeing with a hole drilled throung the centre to support the barrel in side the chamber.
The piston was cast from epoxy with a neoprene sealing face ,the is my first attemp at casting an epoxy piston and im very impressed with the results ..


power? well power is determend by the amout of pressure u can put in it,all my shooting is done at 140psi because im limited to the power of my compressor,i want MOAR, but at 140psi u can still do some considerable damage.

AMMO= just a basic 3" timber nail with a couple of turns of teflon around the shaft, I then cut it up to about the size of an ait riflel pellet ,so basically i get about 6-7 shoots with one nail..

here is couple of videos=

Man you have come quite a ways in such a short amount of time.
looks good you should make some accurate darts and a nice stock for this little beast, and a hp pump for MOAR POWER!!!!!1

like it
at this time when i wish i had a power drill

Very nice gun (and foot). I have may have mastered the huge coaxial piston but my multiple tries at a small one have all failed. Great job on this. Me likey.

thanks, , really appreciate it,,just one question,i need some 4.5 mm ball bearings ,for consistant ammo,and im in sydney australia and cant seems to find any, does anybody from australia have a source???

or maybe even online as a last resort..

Pretty good, better than the other one. Is this one serviceable?

Sort of similar to what I'm making, except mines neater (hey, I have spent a while on it) and bigger.. In fact my co-axial just passed the low pressure leak test with flying colors..

As other members have said, you've come a long, long way in this time.

inonickname wrote:Pretty good, better than the other one. Is this one serviceable?

Sort of similar to what I'm making, except mines neater (hey, I have spent a while on it) and bigger.. In fact my co-axial just passed the low pressure leak test with flying colors..

As other members have said, you've come a long, long way in this time.

unfortuantly not i needed a tap and die to make it servicable,like the last one i had one shot at putting this together without leaks and i nailed it,the last one having a leak,and the power of this is laughable in comparison to the other..

what size pipe and what fittings are you using?, or are they all machined?

Your gun looks alot like mine now.
But mines better

There are several commercial parts (eg. blowgun, QD) but it's basically all machined. Hell, even the chamber is machined from tube stock. (4mm walls anyone?)

After some testing at lower pressure (300ish psi) it's an absolute beast...

Well if thats the case im OUT lol

Im eger to see this device uve made,,ill wait in anticipation

Is yours loud because mine hurts you ears at just 100 psi.

yet another small bore co-axial,what is it like to shoot as I can't get mine to fire yet (piston problems)

Calling 300psi low pressure....Thats about my max pressure [/code]

qwerty wrote:Is yours loud because mine hurts you ears at just 100 psi.

Yeah its loud ,But i dont think its ear piercing not at 100psi at least

@rna- whats it like to shoot?,im a little unsure of how to answer that, its very solid when fired ,it has a little kick ,and accuracy is reasonable considering its size

as for ur piston,id suggest not giving up on epoxy just yet,maybe change the way in how u cast it?? (countersink,neoprene in offcut first, grease offcut,pour in epoxy ,heat lightly with blowtorch but dont cook it, i found it bonds better to the neoprene)

sorry about that, my connecton dropped out

FORE!!!! wrote:thanks, , really appreciate it,,just one question,i need some 4.5 mm ball bearings ,for consistant ammo,and im in sydney australia and cant seems to find any, does anybody from australia have a source???

or maybe even online as a last resort..

.177 air gun pellets? should fit perfectly in a 4.5mm barrel.