hybrid cartridge protoype without burst disk

[POLAND_SPUD]

I think he meant 'hey jsr why don't you use an oring detent and a ball detent?'

[jackssmirkingrevenge]

There was some talk of the combination a couple of pages ago but nothing that wasn't horrendously complicated if I recally correctly.

[killerbanjo]

Been a month and a day, need an update! Also why dont you just use a burst disk?!

Also for pellets you could do this... (Push the skirts so there larger like many spuders do so they can use them in 6mm id barrels.

Edit: wooooops sorry for the picy size

[jackssmirkingrevenge]

Been a month and a day, need an update!

Heh been occupied with other things

Also why dont you just use a burst disk?!

At this point, it seems quite silly not to - but the advantages of a "valveless" cartridge mean it's worth some effort.

Also for pellets you could do this... (Push the skirts so there larger like many spuders do so they can use them in 6mm id barrels.

Tried that too, sadly the skirt is too soft to hold decent pressure.

[jackssmirkingrevenge]

A different take on the fill rig, instead of putting the cartridge inside an airtight chamber, the mouth is clamped against a schrader outlet.

[Labtecpower]

This looks much easier than the previous one!

Do you use delrin for the plugs?

[jackssmirkingrevenge]

Do you use delrin for the plugs?

Yep, all put together with araldite. Also I cut the slot out of the tube using the mill and slitting saw, nice and neat

[Gun Freak]

I like it
Yesterday I was mixing epoxy for a stirling engine and thought, damn, it's been a while since JSR made anything!

[jackssmirkingrevenge]

mixing epoxy for a stirling engine

I wouldn't normally recommend epoxy for applications that require constant high temperature.

damn, it's been a while since JSR made anything!

Been very busy with the day job and it's been mostly a cycle of work and sleep with very little in between.

I like it

One thing I don't like about it is that mix number is limited by the capacity of the cartridge. Pump dead volume is 1.75mL, which means that say the cartridge volume is 1mL, if I flood the cartridge with butane that's 1mL out of 2.57mL which is 36%, so the maximum mix I can get is 11. To solve this I could either try injecting fuel into the pump itself instead, or customising the pump to remove the dead volume.

[POLAND_SPUD]

To solve this I could either try injecting fuel into the pump itself instead, or customising the pump to remove the dead volume.

or you can get a fridge compressor

A different take on the fill rig

I like it - simple yet it does its job

[jackssmirkingrevenge]

... aaaand win!

[youtube][/youtube]

Tried out with a 0.177" cartridge I had made a while ago but hadn't worked with my other fill rig, the above is at 6x.

I didn't need to use a rubber seal, the smooth face of the cartridge mated well with the delrin endcap:

[POLAND_SPUD]

hmmm now that you have a lathe and some delrin.... would you be so kind as to test if it's possible to build a lapped piston valve ?

[jackssmirkingrevenge]

would you be so kind as to test if it's possible to build a lapped piston valve ?

You mean metal-on-metal? Hmmm...

[Lockednloaded]

How's the power for that cartridge? What mix can it take?

[jackssmirkingrevenge]

How's the power for that cartridge? What mix can it take?

With the o-ring set as it is on this particular cartridge, beyond 90 psi or so it will eventually let the BB pop.

In any case, I'm not expecting power to be amazing. At 28x my 0.177" mini was about as powerful as an adult air rifle. For this reason I'll probably move up to 0.22".