How cold is too cold to go out with our PCPs

It doesn’t get nearly as cold in my area as what some of you all are saying about your regions. I think around 22-23F is about as cold as I’ve hunted with an airgun. I’ve camped out in a tent in these temps with airguns on a hunt and I haven’t had any issues. If it’s foggy or if temperatures rise to the point that the ice melts and drips off of tree leaves by midday, I’ve found that oiling and wiping down my rifle with an oily rag before going out helps to repel moisture. My main concern is condensation forming inside of the reservoirs and possibly being forced through the transfer port. I don’t want to rust or corrode parts of the internals. The air is usually around 30-35% RH when I top off a tank I assume there’s some moisture in my tank to be concerned about. I really don’t know if it’s something I should be legitimately concerned about, or which further preventative measures or maintenance work should be taken. 
 
Howdy all, well 20 F would be on the warm side for some of my outings and my Prophet Glimmer didn’t skip a beat and I haven’t see any condensation effects. I think I got down to like 15 F would be on more appropriate, with no wind chill. I spoke to several people who I would say “in the know” and they said I should be fine. EdGun rates his gun down into the teens F.
 
Howdy all, well 20 F would be on the warm side for some of my outings and my Prophet Glimmer didn’t skip a beat and I haven’t see any condensation effects. I think I got down to like 15 F would be on more appropriate, with no wind chill. I spoke to several people who I would say “in the know” and they said I should be fine. EdGun rates his gun down into the teens F.

@blackpaw That’s good to read. One of the PCPs I had out in those temps was an EDgun. I don’t know if you would see effects of the type of condensation I’m talking about until a considerable amount of time passes unless you look inside the reservoir. I watched YouTube video of a guy rebuild a reg on a Wildcat (I think it was a Wildcat) and he had corrosion on the regulator body that he attributed to moisture over approximately a 1 year period. I want to find the video an link it. I recall a nice rug on the floor and an interesting glass-top metal framed table he used in the video. It may have been an Afghan or Pakistani man. Let me see if I can find it.  Here’s the link https://m.youtube.com/watch?v=3tzKar6Ia-0

What I’m most curious about is the reservoir. Taking these guns from outside in such cold temperatures to room temperature storage areas, are any cold weather hunters (below freezing temps) degassing their rifles, removing the regs, and checking and wiping the interior of the of the reservoir to rid them of condensed water vapor? If so, how often? Also, does the reg need to be disassembled and serviced similarly under these circumstances? 
 
I take the airguns out shooting in fairly cold weather all the time. There is a 200-300 psi pressure change in the air tube going from warm to cold and vise versa, depending on the weather. 

Rust forms more prevalently in warm humid environments, and especially if we create these changes by taking things in and out of warm places like warm garages and gun cases. I let the equipment acclimate to the changes, both up and down in temperature, by leaving them in the case for an hour or more so they gradually change temperature. This doesn't allow them to noticably sweat from an instant temperature change when removed.
 
I take the airguns out shooting in fairly cold weather all the time. There is a 200-300 psi pressure change in the air tube going from warm to cold and vise versa, depending on the weather. 

Rust forms more prevalently in warm humid environments, and especially if we create these changes by taking things in and out of warm places like warm garages and gun cases. I let the equipment acclimate to the changes, both up and down in temperature, by leaving them in the case for an hour or more so they gradually change temperature. This doesn't allow them to noticably sweat from an instant temperature change when removed.

Uh oh. I certainly haven’t been doing this using the case before going out. Living in a humid region the point of humidity isn’t totally lost on me. Hunting in the cold with PCPs is newer territory for me. The drop in pressure between inside and outside temps of around say 30 degrees is not too big a deal to me. It’s not like I’m going out to empty a magazine on a hunt, at least not most days. Thanks. Y’all are coming with some useful info in this thread. 
 
Howdy all, well 20 F would be on the warm side for some of my outings and my Prophet Glimmer didn’t skip a beat and I haven’t see any condensation effects. I think I got down to like 15 F would be on more appropriate, with no wind chill. I spoke to several people who I would say “in the know” and they said I should be fine. EdGun rates his gun down into the teens F.

@blackpaw That’s good to read. One of the PCPs I had out in those temps was an EDgun. I don’t know if you would see effects of the type of condensation I’m talking about until a considerable amount of time passes unless you look inside the reservoir. I watched YouTube video of a guy rebuild a reg on a Wildcat (I think it was a Wildcat) and he had corrosion on the regulator body that he attributed to moisture over approximately a 1 year period. I want to find the video an link it. I recall a nice rug on the floor and an interesting glass-top metal framed table he used in the video. It may have been an Afghan or Pakistani man. Let me see if I can find it.  Here’s the link 



https://m.youtube.com/watch?v=3tzKar6Ia-0





What I’m most curious about is the reservoir. Taking these guns from outside in such cold temperatures to room temperature storage areas, are any cold weather hunters (below freezing temps) degassing their rifles, removing the regs, and checking and wiping the interior of the of the reservoir to rid them of condensed water vapor? If so, how often? Also, does the reg need to be disassembled and serviced similarly under these circumstances?

I've always wondered if it produces a "cloud" of moisture inside of the air cylinder or scuba tank filling with different temperatures. I know my cylinder will get warm from expansion if I fill an empty cylinder too fast, and will go very cold when removing the air quickly as well. It would be cool to fit a micro camera inside an air cylinder or scuba tank to see if these things happen when filling and dumping air.