any lower limit on operating at low temps?

[PaulStafford]

I got my first rifle this spring, after temps rose to humane levels here in NW Montana.

However, I anticipate trying to shoot through the winter. My action and barrel are SS. At times, temps can get quite low. Knowing metal gets more brittle at low temps, and the pressure impulse in chambers quite extreme, is there any safety issue in shooting in low (0F) temps? fellow Montanans?

 

[seanh]

Re: any lower limit on operating at low temps?

Of course there is a limit but your temps aren't going to be close. The 700's have been used in some extreme environments with out issues regarding brittle material. Your biggest issue will be your ammunition performance.

 

[bowstryder]

Re: any lower limit on operating at low temps?

One thing to remeber when shooting in colder weather. I let my rifle sit outside for a little bit of time to get "acclimated" it helps with scope fog and such. though your first cold bore shot will be truly cold bore. hth

 

[kraigWY]

Re: any lower limit on operating at low temps?

Excluding the sweating from taking the rifle from the cold-warm-cold bit there is no problem.

Worse I got was 70 below at Galenia. We jumped in on the Yukon rifle and set up a rifle range. AR's (M16s) worked fine. Even my Remington 700 bolt gun in 223 did good.

Went out several times in the winter with AK Natives (Eskimos) in the winter, no problem.

Biggest deal is taking a gun from a warm tent outside. Leave the gun outside and you wont have any problems.

 

[PaulStafford]

Re: any lower limit on operating at low temps?

thx guys, good to know

 

[Schleifalot]

Re: any lower limit on operating at low temps?


The colder the ammonition, the slower the powder/propellant burns. At my locations this can lead to about 0,75 to max 1 MOA difference between summer (+25°C) and winter (-5°C). Sorry, no extreme difference in temperature.

Usually I carry the ammo in my breast pocket inside the jacket in winter, so it stays moderately temperated. It helped to reduce differences in the burn rate.

 

[kraigWY]

Re: any lower limit on operating at low temps?

I think extreme cold affects the shooter more then the rifle.

 

[sirhrmechanic]

Re: any lower limit on operating at low temps?

According to my databook, I've shot cold bore at 34 below here. That's with the rifle at that temp.

The POI definitely changes in cold weather and every c. 20 degrees brings with it a noticable, though small, change in cold bore POI. After a barrel warms up, the POI can shift a fair amount.

In areas where you have an annual temp swing that can be 120 degrees (as we have)... it is important to keep really accurate data books and dope records!

As far as function... lubricants should be approved for cold weather. Of note, up here in the Northeast, we see more trouble with semiautomatics in changing weather conditions right around freezing. When you get those foggy, rainy, snowy, 28 - 34 degree days, condensation can get in to mechanisms and freeze. This happened to me many years ago w. a BAR hunting rifle. Firing pin went sluggish and it went click instead of bang... three times. Third time it fired and I got my deer.

But metallurgy, etc. won't be affected until temperatures below which you probably can't survive, much less function.

Of note, there have been stories of German equipment failing on the Eastern Front due to cold c. 1943 - 44.... Rifles, breeches, barrels, etc. that failed in the cold. But I always wondered if some QC issues or sabotage (bad heat treating?) in manufacture didn't play a role. Or was it just good allied propoganda to make the Wermacht look less formidable? Were any cold failures really documented? How about in Korea w. US weapons?

Anyone know if Picatinny Arsenal/ARDEC has done cold failure tests... or at least made them public?

Cheers,

Sirhr

 

[BlackOps Tech]

Re: any lower limit on operating at low temps?

Understanding that the temperature lapse rate is 2*C (38.6*F) per 1000 feet, and the number of Boeing products flying around in Class A airspace (typically tops out at around 60000 ft), you can imagine that the temperatures are quite unfriendly.

I don't believe that the stainless steels and other alloys used at altitude have suffered any catastrophic failures due to the extreme low temperatures.

Although I can't speak to the use of 416SS in airplanes, I can't see the degradation of 416SS in the far higher temps on the ground being so severe that brittleness would be an issue.

Just a thought....

 

[Beef82]

Re: any lower limit on operating at low temps?

Having shot numerous firearms around or below -40F I've never had any structural issues. I'm a mechanic and aside from pigmetal cast parts in some switches and latches we don't worry a bit about metal failure due to cold and we've seen -65 no wind chill, wind chill doesn't affect parts. Liquid nitrogen which is used to freeze and break steel is -300 something. Glues and plastics are another story, many of them, can't take -40 and colder, but most are ok as long as you're not significantly flexing them. Cartridges act and sound different, and action parts can slow, cleaning all oil out of the bolt is commonly recommended, even running semi autos dry is not unheard of, though with autos that assumes short strings, some of the newer lubes might not thicken up in the cold, I haven't checked, I've done enough shooting in that weather to know its not fun and generally avoid it.