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BCSteel · Member

What temps can I use a 12g co2 down to and still get decent performance out of them? I picked up a 2240 the other day and wanted to check it out but I can only shoot outside and the temps are around 32 + or - 4 or 5 degrees.

AirGunEric · Site Admin

The second last calculator here:

http://www.airgunhome.com/pages/calculators.html

is for Co² pressures at a specified temperature. So, for example, at 32 degrees F (0* C) Co² vapor pressure is around 506psi- this as compared to around 850psi at 70*F- so you have 59.53% of the pressure at th lower temp- meaning your power is going to be down somewhere in the ballpark of 40% vs. that 70* day. There are other factors that may vary this slightly beyond just the temperature- but the calculator is good for a basic guideline.

Bottom line is- you need to keep that Co² warm, live with the decreased output, or use another sort of powersource.

BCSteel · Member

I even looked at that link just the other day Rolling Eyes

So I think that co2 works on expansion right? So the colder it is the less it expands and the less quickly it does so, right? So is that what causes the reduction in power during the cold, slower expansion? I'm just trying to understand how it all ties in together.

2RCHA · Veteran Member

I've tried using hand-warmer's to keep the Co2 temperature up. Just take one, or two, and wrap them around the Co2 tube, and hold in place with a couple rubber band's,,I also take one of my little boys black sock's and cut the toe end off, and slip it over the hand-warmer's/Co2 tube/barrel,, I didn't notice a difference with the performance, mind you when I tried it wasn't as cold as it is now(-10C/Toronto), It would be interesting to find out how well this work's with real Cold temp's, atleast -15C,,Anyway's, I'm sure I won't have to wait too long to see,LOL, Andy.

AirGunEric · Site Admin

Yes, expansion and evaporating- the lower the temp the slower and less it does it. Air is nowhere near as prone to this- so pump guns, PCP or spring guns are usually the only real ways to "winter shoot" with similar power as in warmer weather conditions.

You can still use your Co² 2240- but it won't shoot as far or as rapidly as it would in warmer conditions unless you are artificially heating up the Co².

BCSteel · Member

Ok, thanks guys. I might try out that hand warmer idea tomorrow.

Alstone · Moderator & Site Supporter

Hi BCSteel
I shoot alot in the winter using Co2 guns and find that once the temp drops below 16c the proformance drops off, for example one gun I have will shoot between 500-550 fps at 20c but at 16c it shoots at 400fps which is still usable out to about 15m, the only thing is that you have to alter the sight to reset you poi, the only problem with using heaters is that the fps get's erratic with the constant changing temprature, hence the poi keeps changing. The key to shooting in cold weather is a constant temprature above 16c, anything less don't bother.

Al

BCSteel · Member

So I went out and tried the new gun today. It was pretty cold 33F and lightly snowing. Loaded the co2 in the truck while everything was still warm, got a couple of those disposable hand warmers going and taped them to the co2 tube. Only went through 1 tube though so I dont know if it was really making any difference. Did get about 25 or 30 hard shots out of it though and at least got to run some lead through it. Damn that tirgger is heavy Shocked

AirGunEric · Site Admin

If it's a new gun it needs to be "broken in" for awhile. Your trigger will likely lighten up a bit over time- but you may also want to look into changing the spring on it if it's too heavy for your liking, even after a few hundred shots through it.

BCSteel · Member

I was thinking about taking it apart and smoothing out some of the contact parts on it and checking it out again to see how that goes.