Piston sliding room

[pat123]

I have been working on a piston for about a month now. I am almost finished all I need to know is how much room does the piston need to slide back, about and inch? i'll post pictures when it is finished.

thanks
Pat

[DYI]

For a coaxial, the piston should have a stroke roughly equal to 1/4 x barrel porting ID. For a barrel sealer, it can have a bit more travel than that, probably 1/2 barrel ID or so.

[pat123]

thanks this is my first piston. the port is 1.5 in so I'll make it 3/4inch

[MrCrowley]

Depends on the I.D of the barrel.

In a co-axial the piston should slide back 1/4 of the barrels diameter.

In a barrel sealer I would say the barrels diameter as a max slide back distance. So if you had a 40mm(1.5") barrel, I would say 40mm maximum and probably 20mm(3/4") minimum.

It doesn't really increase performance a lot in bigger bore guns as long as you keep the pilot volume to a minimum and have a decent pilot valve.


Damn, DYI beat me to it