Planning on bulking my QB78d and would like to add a longer main tube, more shots and I don't want to cut my new stock. I there a direct fit tube out there, sticking with Co2.
John
Planning on bulking my QB78d and would like to add a longer main tube, more shots and I don't want to cut my new stock. I there a direct fit tube out there, sticking with Co2.
John
I saw this during my search, is there a issue using this tube for Co2?
Bulk filling C02 you should see no real difference in FPS from what you have now unless you overfill it by supercooling the tube and doing a hot fill.
(Bob opened my eyes to this and it can end in disaster)
I run mine on HPA at 1600 psi in the 500fps bracket because this velocity works well for a target rifle. You do need to back off the spring and/or restrict the port to stay at 500 with HPA.
But the shot count is great even on the stock tube.
Sean
Other than it being twice as strong as it needs to be for Co2, no.
I'd say I care- but I'd probably be lying...
I wish I could give some helpful advice but I modified my valve for power, and added the velocity adjuster to control it from a 35 shot plinker to a 9 shot monster(and that doesnt take many turns). Should you make it breathe a little too freely the tranfer port is a place to concentrate on regaining shot count.
For every mile of road, there's two miles of ditch
Order placed, maybe one day I'll make the leap to HPA
On the QB's it's a really easy leap...more like a tiny step.
When you assemble the gun just use silicone grease/lube and nothing else. Then switching to HPA is as simple as filling it with HPA.
Sean
is not the pressure limited to 1500 psi tho?Originally Posted by SeanMP
unless further mods are made?
Everyone is entitled to an opinion ...but only mine is right!
DAVE G
well I've stretched it as far as 1800psi. The limiter is the hammer/hammer spring. Bob has a fair bit of data on mods and pressures.
You also want to give the valve to valve stop block clearance a quick check if your planning on going to very high pressures. Ideally this clearance should be as tight as possible. I epoxied a thin shim washer onto my stop block.
Sean
Posting Permissions
Reply With Quote
