Pluging Up One Co2 Cartrige in a Two Cartrige Gun to Get More Shots ?

[mike@nds]

I just use an empty cartridge.

But some 3/4" delrin rod could be cut to length.   

[Ribbonstone]

I just took the front end cap’s little piercing “nub” out of play.

DSCN0083 by Robert Dean, on Flickr

Only counted “good” shots….not the ones at the end where velocity had fallen way off.

Shot it with a full two full 12gr , one that didn’t get popped and just took up volume. (26 shots)

Shot it with an already empty 12gr., which has to count as empty volume the other 12gr. has to fill. (23-24 shots)

Shot it with two full 12gr. (54 shots)


So long as I was feeling Qbish….fgot around adding a lower o-ring seat/o-ring to the old QB tube size bulk fill adapter to also work with the current type QB tubes.


Forgot….we got new guys here.

Some years back, the QB tube and end cap changed.


The internal length didn’t change...has to be two 12gr. long inside to work.....but the new tubes are longer, the end caps deeper, and the tiny little vent hole father back...so the o-ring on the end cap is father down.

DSCN2857 by Robert Dean, on Flickr

So the bulk fill end cap wouldn’t work on a new tube because the sealing o-ring was above the little vent hole in the tube.

(they hide the little vent hole in the threads from the end cap...but it’s there)

Added a new o-ring seat and o-ring to that adapter so it could be used with either type tubes.

[Nvreloader]

Ribb
I just received a brand new 78 pressure tube today, and just checked it, I can't see a vent hole in the threads,
I even put my long fiber optics lite inside and turned out the lights, can't find a hole anywhere.

So going on the info, I believe that this must be NOS > new Old stock from before the hole drilling age?
Do you know if the threads are US or metric for the cap?
I also plan on running bulk filled.

Tia,
Don

[Ribbonstone]

Checked the 3 12gr. tubes I have on hand..two old, one new style...all have tiny little vent holes, although one is hidden under the barrel.   

New 78 tubes are about 3/8in longer than the old tubes….and the end caps deeper by the same amount. New bare tube should run about 15 3/8”.

No idea what the thread size….old tubes have the little vent only down about 3 threads….new tubes put their length to use and the tiny vent is down about 10 threads.

Their Archer’s ofrMike at Flying Dragons should know the thread.


Think the idea was to give that vent a bit more time to vent residual gas….if it didn’t leak at that little vent, would get a real loud champagne cork sound (and possible fling the cap a good long way even with just 30 or 40 PSI left in the tube).

So I’m kind of hoping the little vent is there….otherwise, would get exciting once the threaded collar  came disengaged.

Got one old picture….can barely see the vent (on an old tube, so it’s way up near the  top of the threads.)

DSCN2853 by Robert Dean, on Flickr

Red  *  would be about where the vent would be on a new tube (Although on my new tube, it's at 12 o'clock and hidden by the barrel.)