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Carl Quick's LiteWieght 2240

So for about the last 24 months, I've had her on a serious diet. Now I am happy to report that she lost nearly 13 ounces and is feeling so much better. And let me say one thing, when I pick her up with one hand now she is light as a feather. Well, almost a feather.

Things I have done so far:

OEM main tube was lightened by me.
Barrel is OEM and trimmed down by me.
Main tube plug is made of Delrin by me.
Gas cap is aluminum, comes from HPA and bored out by me.
Hammer is made from Delrin by me with a modified 1701P striker.
Valve is an aluminum Disco rear end with a brass Pro-Top by Anthony.
Trigger grip frame is aluminum by Bluefork Design and then hogged out by Gregg.
Front barrel band is aluminum, made by Anthony, drilled by Rich and milled by me.

Quickster47



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Gas velocity - port hogging relationship

June 29 2012 at 8:23 PM
Airfierce  (Login Airfierce)
Crosman Forum Member
from IP address 66.81.28.107

I don't have much experience with airgun mods, also haven't been on the forums for quite a while.

I got to wondering about opening up ports. Seems that where you have a large volume chamber and a small orifice for air to pass through on its way to being exhausted, the restriction would work under the venturi effect. This would cause the gas to speed up exponentially at point of restriction, effectively causing a ram induction force into exhaust, increasing volume more quickly and speeding gas flow.

If that transfer port or whatever is opened up then there would be a loss of venturi effect and loss of gas velocity. Has any research or data crunching been done regarding this, to show where an intended improvement actually causes a net loss in pressure or gas velocity behind pellet? I can see advantage to smoothing contours or sharp edges however it seems there's a danger of backpedaling when hogging ports. Apologies if this has already been over thunk and discussed ad infinitum...

 
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