Air Gun Home :: View topic - what systems are effected by cold weather?

walter · Veteran Member

ive heard about springers in the cold but does it effect the multipump guns as well? should i expect it to effect my 1377? thanks for the edvise. walt. Smile

broommaster2000 · Moderator

Probably, but I don't think enough to make a huge difference. Some of the other members have some more experience with this but the times that I had been shooting outside in the cold with my PCP I didn't notice any difference.

rsterne · Moderator

Pumpers can be affected by the cold, but to a much lesser degree than CO2.... When you pump the gun, each stroke raises the air pressure, creating heat.... When the gun cools, that loss of heat in turn reduces the pressure of the air in the valve.... That is why in an extended shooting session with a gun that requires lots of pumping you will notice the gun getting warm....

It works this way.... If you are doing a continuous shooting session, the gun will be warmer and the pressure and velocity stable.... If you pump the gun and then let it cool down, you will find that your first shot will be a bit slower, and then each successive shot will be a bit faster until the gun warms up again.... The larger the difference in temperature, the greater the velocity loss.... If it's really cold, and you pumped the gun inside before going out, the loss can be significant.... Once the gun is cold, when you pump it, it will lose heat very quickly to the cold metal and take more shots for the velocity to return to what it was inside.... It may never quite reach what it did inside if it loses heat quicker than you can put it in....

There is a way around this, however.... You can add a pump or two to make up for the loss of pressure due to temperature.... Just be aware that it happens and do the testing ahead of time to know how many extra pumps it takes.... On my Uber-Carbine, I required 20 pumps instead of 18 to have the velocity the same after the gun sat for a while compared to continuous shooting.... and that was inside at 70*F.... At freezing temperatures, it would have been more.... At lower pressures, there was less difference because less heat was developed during the pumping.... If I did a continuous string at 10 pumps and then let the gun sit to cool down.... it was only down a few fps.... 11 pumps and cooling was still too much although might have been perfect in freezing temperatures.... but I never tried that....

PCPs should have basically no difference due to temperature except possible hammer drag because of cold lubricants.... Springers do suffer a bit from lubricant drag.... CO2 is hopeless at freezing tmeperatures as the gas pressure drops dramatically....

Bob

1377x · Member

i have used my 1377 all winter long in sub zero weather the only problem happened when i left it outside all night sub zero.the gun had to warm up to seal properly.this winter i will store a couple of pumps at the end of the day

walter · Veteran Member

thank you for the info! Smile

walt.