SpudFiles

Hey
When my exams finish (5th November) i will begin work on my 8mm barrel sealer sniper gun. I have draw up plans, i posted them on the pellet gun topic, but its not the right place for it i think..... So I'm making a topic about it, the diagram is not labeled but it should be self explanatory, any comments/suggestions/questions will be much appreciated.
NOTE: The diagram is roughly in the right ratios...

Looks good marco what are you using for the pilot?

looks like hes using custom blowgun.

how big is the pilot hole going to be?

Yup, custom blowgun.

Im basing the blowgun of a commercial blowgun, and a custom blowgun i made. It will be around 8mm

As you know be sure to minimise dead space

looks cool, the only thing i don't like about coax cannons is that they limit breech loading but they do allow the cannon to have better lines.

its pretty similar spec to my plans but i'm usinf 6mm bore and 15mm chamber, what pressure are you going to run it at? and you should definitly make the wooden stock in the style of an exsisting sniper probably one with an integrated silencer becasue your barrel will look fatter than a normal gun's becasue its a coax kind of like this http://world.guns.ru/sniper/sn20-e.htm

ALIHISGREAT wrote:looks cool, the only thing i don't like about coax cannons is that they limit breech loading but they do allow the cannon to have better lines.

its pretty similar spec to my plans but i'm usinf 6mm bore and 15mm chamber, what pressure are you going to run it at? and you should definitly make the wooden stock in the style of an exsisting sniper probably one with an integrated silencer becasue your barrel will look fatter than a normal gun's becasue its a coax kind of like this http://world.guns.ru/sniper/sn20-e.htm

You can put breach loading on a coaxial.

I'm hoping for max running pressure of around 300-400psi. But i only have a bike pump up to 160psi, which explains why my chamber is almost as long as the barrel. I'm using compression fittings so when the time arises i can cut down the chamber.

The barrel is 10mm OD, which i think is thinner than the .308 which was my inspiration for the design.
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it looks good as marco, i cant wait to see ur custom pilot working do you reckon it will have a better flow then ur average blowgun?

(oh and Mr.Russ u nicked my old sig....its cool though chap)

I know you might not get airsoft easily in australia but how easy is it to obtain one of these It's an "m16 AK machine gun" but actually based on the H&K G36

You'd get ready made stock, grip etc. to graft on to the rifle to make it more ergonomic and attractive.

Marco321 wrote:

ALIHISGREAT wrote:looks cool, the only thing i don't like about coax cannons is that they limit breech loading but they do allow the cannon to have better lines.

its pretty similar spec to my plans but i'm usinf 6mm bore and 15mm chamber, what pressure are you going to run it at? and you should definitly make the wooden stock in the style of an exsisting sniper probably one with an integrated silencer becasue your barrel will look fatter than a normal gun's becasue its a coax kind of like this http://world.guns.ru/sniper/sn20-e.htm

You can put breach loading on a coaxial.

I'm hoping for max running pressure of around 300-400psi. But i only have a bike pump up to 160psi, which explains why my chamber is almost as long as the barrel. I'm using compression fittings so when the time arises i can cut down the chamber.

The barrel is 10mm OD, which i think is thinner than the .308 which was my inspiration for the design.
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what i meant was its harder to put breech loading on a coax.

and wouldn't the trigger pull be very hard at 300-400psi?

all you have to do is have the trigger longer on the finger side so that you can get more leverage to open it. if not then you could open it with hydraulics

if not then you could open it with hydraulics

I always wanted to do something like this, it would make an easy way of making an efficient bullpup, having your blowgun pilot at the back without the need of a long hose so it's efficient, while having your actual trigger further forward so you can shoulder it comfortably. All you'd need is a couple of syringes (the same diameter will do but if you're crafty enough you can play with different diameters and resulting travel), some tubing and fill the lot with water.

Bad diagram to show what I mean:

jackssmirkingrevenge wrote:

if not then you could open it with hydraulics

I always wanted to do something like this, it would make an easy way of making an efficient bullpup, having your blowgun pilot at the back without the need of a long hose so it's efficient, while having your actual trigger further forward so you can shoulder it comfortably. All you'd need is a couple of syringes (the same diameter will do but if you're crafty enough you can play with different diameters and resulting travel), some tubing and fill the lot with water.

Bad diagram to show what I mean:

i think that would be quite hard to do, how much of a performance difference would a smaller pilot volume give if you piloted like that as opposed to having a method like on spanerman's paintball sniper?

Theoretically, cutting the pilot volume in half means the pilot chamber will empty in half the time, meaning a quicker valve opening and therefore better performance.

As to actual percentages of performance increase, it gets a little complex - perhaps someone with a QEV/sprinkler valve cannon and a chrony could make a graph of pilot volume (ie pilot blowgun hose length) vs velocity for a given projectile?

jackssmirkingrevenge wrote:Theoretically, cutting the pilot volume in half means the pilot chamber will empty in half the time, meaning a quicker valve opening and therefore better performance.

As to actual percentages of performance increase, it gets a little complex - perhaps someone with a QEV/sprinkler valve cannon and a chrony could make a graph of pilot volume (ie pilot blowgun hose length) vs velocity for a given projectile?

i would just use a bigger pilot valve.