Quote Originally Posted by cringe View Post
Hi, several years ago I experimented with building a 'sparklets' bulb powered gun. Not a rifle but a double barrelled .410 bore pistol, I was amazed at the power! and during my experiments I found that co2 works better in larger bores. I guess it's to do with expansion rates. I did not progress any further, as I don't like porridge! but it could have been even better if I had fitted some sort of heater device.
best regards Al
It’s probably nothing special about CO2, but simply F=PxA

A larger bore gives you a greater area, pressure is constant (particularly with CO2), so force increases. If I’ve done my sums correctly a 410 bore is 85mm2, and a .22 is 23.75, so you’ll be pushing the projectile with nearly four times the force

Velocity will probably be down (you may have more force but you’ve also got more mass), but as the limits are set on energy as you say it’s not really a project that can be safely conducted in the uk.

As for the springer vs co2 argument, a springer is in a sense more efficient as the transfer of energy to the pellet is adiabatic. However as the waste heat in a CO2 gun is created in the sparklet factory not the gun, it’s a theoretical point as far as the shooter is concerned. As for manners, I have a nicely set up FWB 127, and have just got an SFS Snipe, and tbh for both those guns (and also any good CO2 gun) the limiting factor on accuracy is me. So any slight benefit CO2 would have is moot

I would agree that for an average gun on an average day CO2 is likely to be more accurate though.