how is a piston vavle any more powerful than a normal sprinkler valve?

this is another little piece of crap i made its surprising how powerful it is haha, i shot myself in the leg and left quiet a bruise

this is my first pneumatic cannon, pretty basic, had a few problems as it was my first, modding the vavle, as i hadnt looked into how sprinkler vavles work i couldnt figure out why the air wasnt releasing into the barrel, but i figure out i had to slow the air flow down in the vavles chamber so i ma...

hmmm when i vent the top chamber of my srinkler vavle all the air just goes out the blowgun and none releases into the barrel, its like the diafrag, (spelling) isnt pushing up when air is realesed is that because the whole u take the guide rod out of is too large, i have been trying to figure this o...

ok i cant get my vavle to work its all air tight there is a slight leek at about 30-40 psi but it dosnt want to let any air into the barrel it just all blows out the blowgun, any ideas ?

i know this isnt a help section, but i have this same vavle, ive done everything as said, and it should work but for some reason it isnt opening the are from my chamber goes straight out the blowgun not letting any air into the barel its like it not opening but stuffed if i can figure out y, any sug...

i need help plz totally new to making cannons i am making a pneamatic cannon and have bought and moded the easy no drill sprinkler vavle and i pump up my chamber to about 30 psi only to see if it will realease into the barrel but it dosnt, it all just blows out the blowgun back end and i cant get it...