Increasing Fn 303 or automag powertube or bolt psi output capabilities ?

[Jono]

Iv read that the average psi out powertube only hits like 90psi this makes sense when paint bursting is a consideration but In the case if a fn303 less lethal launcher it shoots solid hard shaped projectile. Id like to raise the powertube psi out for a faster jet of air this should allow for less over all air needed and or faster shots made more air efficient. Where at is the psi output being limited? In powertube? Like between bolt pin and power tube orings? If I knew where then I could hopefully increase flow for a higher psi and a quicker chamber dump.mll

[superman]

The problem with the mag valve is not the efficiency of the shot it is the pressure at which it needs to do it. If you can drop the operating pressure and keep the efficiency it will likely be come something along the lines of a mini or axe.

I do not recommend raising the dump chamber pressure as you will have problems breaking paint.

[uv_halo]

The Automag, the FN303 and the Axe/Mini all rely on a pressure and volume combination to control velocity. They all have a fixed dwell, unlike a lot of electropneumatic spool valves (shocker, ion, etc). With the Automag and FN303, they have a fixed dump chamber size, and you adjust the pressure for velocity. With the Axe/Mini, you have a fixed pressure supply, and you adjust the dump chamber volume for velocity. Technically, the Axe/Mini could have their regs adjusted to go higher but, not that much higher (i.e. you can't double the pressure and halve the dump chamber size)


FYI, the FN303 inputs 3K PSI from the tank and, the built-in regulator drops the pressure to around 850PSI. The FN303 throws the heavier (8.5g) projectile at 280FPS because it has a much larger dump chamber (nearly 2x) than the Mag. A factory FN303, firing a first strike, or a paintball (3g) cannot adjust the pressure low enough to get anywhere close to field legal. Many folks de-volumize the dump chamber to get it to work for paintball (that and dropping the magazine spring pressure).

[superman]

I have devolimized a few fn-303's. I think you could also swap out the spring pack with out devolumizing.