Compression Theory

[sprayandplay08]

Ok I have Another dumb theory,
When Filling A C.C With Spray have the potato at the top of the barrel then put the cleanout on . When you press the potato into the barrel it compresses the mixture by decreasing the distance the gas can occupy

Sorry i know my theorys are way off

[Biopyro]

Nope this has been mentioned before and is pretty common. You do have to adjust your fuel ration if you're using a metered cannon

[sprayandplay08]

yeah but i mean with spray and pray not a propane gun well then i'm just gonna stop posting then and just read

[SpudFarm]

i do it all the time on my small combustions

[psycix]

Note that the potato might shove back up half of the barrel when you stop ramming it.

[sprayandplay08]

when i did that there was a small amount of blow by

[jimmy101]

when i did that there was a small amount of blow by

If there was any blowby then you probably defeated the purpose.

A very tight fitting spud in a 2" barrel might seal well enough, and have high enough static friction, to get the chamber up to ~10 PSIG. That would be a ~1.7X hybrid. If you calculate your fuel ratio for the chamber+barrel volume, partially load the spud to seal the system, and run the fan to mix the fuel, you might be able to get a small hybrid ratio by shoving the ammo as far down the barrel as you can without having it leak or immediately pop back out the barrel.