QEV question And the effect of Chamber Ratio.

[socoj2]

1st.. a 3/8s QEV, would this be large enough for what size chamber...
It has a Coefficient of Volume of 2.98. and is good for 178 SCFM@100 psi


Next question.. With a 48"x 2" barrel a Chamber volume of 65 Cubic inches and 80 PSI nets me 240 FPS.. This cannon is going to shoot nerfs so that is right where i want to be.

How ever. Should i increase the chamber size and lower the pressure, just wondering if anyone has dont this to see what kind of flight performance you get with a large volume/LP vs Smaller volume/HP

[jackssmirkingrevenge]

1st.. a 3/8s QEV, would this be large enough for what size chamber...
It has a Coefficient of Volume of 2.98. and is good for 178 SCFM@100 psi

The question is whether it would be large enough for what size barrel - for a 2 inch barrel, it's not a lot, but for nerf and with a long enough barrel you should be fine.

The higher the pressure and larger the chamber, the more power you're going to get. However, for a certain valve and barrel length, increasing the chamber volume will increase power until you reach a certain threshhold, after that no matter how much larger you make your chamber, you won't get a noticeable increase in power.

With pressure on the other hand, the more pressure you add, the more power you get, simple as that, there's no limit. For small calibre launchers especially, low volume high pressure is certainly better than high volume low pressure.