Why do 870's freeze?

[jon_in_wv]

I use Mobile 1 synthetic on all my firearms. Mobile 1 thickens at a much colder temperature than regular oils. I would suspect if you lube your weapons with it you won't have to worry about the cold.

 

[barnbwt]

Cold affects stuff in firearms by two mechanisms; thickening/stiffening of liquid/flexible compounds, and thermal expansion (or contraction, rather).

If your bolt is dry, that doesn't change things for the firing pin. If the FP channel and spring are dry, the only remaining physical mechanism for a change in operation from temperature is thermal expansion. The FP, channel, and spring are all the same material (steel) and have the same expansion factor, so the cold cannot affect their fitment to one another.

It's either gunk left in the FP channel, or nothing. Or maybe water if you give the guns a good soak before stepping out . Graphite or bare are the only "lubes" that won't have long since clouded/thickened at subzero. I don't suppose the gun is held (in a blind or something) in such a way that your moisture-laden breath can condense/freeze onto it?

I'll also ask "why the heck" are you outside in those temps? True <-20 weather will frostbite exposed skin almost instantly, and winds causing -80 would be so high that you couldn't possibly keep yourself stable when aiming . How do you expose a finger to pull a trigger without frostbite or crippling numbness, since gloves don't insulate well enough at those temps?

Why not just keep a chemical "hot pack" between your mitten and the receiver?

TCB

 

[Deltaboy1984]

Never had it happen but I never hunted in weather much below zero in The mid South.

 

[JohnKSa]

Mobile 1 thickens at a much colder temperature than regular oils. I would suspect if you lube your weapons with it you won't have to worry about the cold.

It should perform about like BreakFree CLP in the cold. They both use the same synthetic oil as a base unless one or the other has been reformulated.

 

[oneounceload]

At those temps, I would be more concerned with my ammo giving me bloopers before the gun malfunctioning........

Having previously lived in ND where winter temps were averaging -35 regularly, there was no way I would be outside. Our safety guy showed us what happened to your skin after 20 seconds or so if it wasn't covered completely - the risk of not only frostbite, but serious risks including death aren't worth it- even for a pheasant.

Add a little moisture as has been mentioned, and the gun can freeze together, like licking the flagpole in A Christmas Story

 

[DM~]

Can't agree. Pull your gun out of the truck and by the time you tromp through the snow to your blind it is damp. Haven't seen much dry cold air up here. Maybe snow in KS is dry but ours is wet and a wet cold Michigan day makes for horrid hunting conditions, unless you know how to dress. The humidity up here is different then where you are for sure as we are surrounded by water on three sides of this state. Michigan has the second most cost line in the United states with Alaska being number 1. Michigan is hummid all four seasons up here.

You keep saying "up here", would that be in the UP??? Because Michigan being "humid" for all four seasons, isn't what i've experienced in Michigan.

DM

 

[blarby]

Easy fix ?

Zip tie one of those "shake and bake" hand warmers to the receiver !

You could loop behind the trigger guard very easily. Not permanent, not pretty, but i'm dang sure it would work.

 

[Cryogaijin]

Errr, lolwut?

I know it is anecdotal, but having taken my 870 out numerous times between -40 and -50 in Fairbanks, I've never had a failure to fire.

 

[AI&P Tactical]

Don't know about the UP as I am in the middle of the state about 8 miles inland from lake Michigan. Winter humidity can be high as in 90's to a low in the upper 60's depending on what systems come through. Anyone can verify this on any weather site. Seldom if every do we have dry air. The lakes are wet and snow is wet. Yet, our 870's never freeze up which is the point of the OP. More mis-information against a model that has been around for over 63 for a very good reason, it works when needed.

 

[Uniquedot]

I've never had anything like this happen, but I can see how it could happen with any weapon of the sort in the right conditions and improper lube.

 

[45_auto]

I would recommend he consider the ammo he was using may have gotten damp because it was taken from a heated auto or Cabin right out in to the cold.

You believe that heated objects cause condensation to form on them in the cold?

You really believe that those electric defroster strips in the rear window of your car eliminate the condensation on the window by causing the window to get COLDER?

 

[Kernel]

At -20 F there is essentially zero water in the air. I don't care where, or what part of Michigan, you live in. It's physically impossible for air that cold to hold any appreciable amount of water. As an illustration - a cubic foot of air would have less than one drop from the tip of a sharp sewing needle – less than 1/10th of a grain of water. (That's the same “grain” we use in reloading. 7000 to a pound.)

And the term “relative humidity” is virtually meaningless at that temperature.

If it's that cold, and water is getting into your action, it's not coming from the outdoor atmosphere. I suspect The Virginian was on the right track. Taking a cold gun into a warm house, or car, will cause condensation to form on it. Not just the outside. Deep inside the action as well.

When the temps get low it's best to keep your guns in the cold all the time - instead of taking them back and forth from cold to hot. Leave them in the trunk of your car, a shed or and unheated garage.

 

[DM~]

Don't know about the UP as I am in the middle of the state about 8 miles inland from lake Michigan. Winter humidity can be high as in 90's to a low in the upper 60's depending on what systems come through. Anyone can verify this on any weather site. Seldom if every do we have dry air. The lakes are wet and snow is wet.

I'm a little further inland from Lake Mi. than you, and i don't have the humidity problem you do. I'm just outside of the lake affect snow too, so i don't get all that extra snow either...

In fact, i hang cloths out on the cloths line all winter long, and they dry quite fast MOST days. If there was a humidity problem, i'd have trouble getting them dry, and i don't...

I guess i'm glad i'm not closer to the lake!

As for 870's, i've NEVER had one freeze up....not here, and not in Alaska, out in some very cold weather.

DM

 

[jon_in_wv]

It should perform about like BreakFree CLP in the cold. They both use the same synthetic oil as a base unless one or the other has been reformulated.

I agree that it "should" but in my experience that doesn't play out in reality. While CLP is supposed to be good to -50 I remember the numbers being a lot warmer than that in my combat training. (I don't remember the exact temp that was 20 years ago) I stuck with CLP for a long time after the Marine Corps because I figured if it was good enough for the Marines it was good enough for me but I noticed that CLP does in fact gum up and leave residue in my weapons. Mobile 1 is supposed to flow to about -35 degree, doesn't leave any gum or residue and my weapons feel "slippery" and clean up much easier with Mobile 1. CLP worked fine for me for a lot of years but I just prefer the performance of Mobile 1 and its a lot cheaper too.

When I lived in Minnesota I tried Mobile 1 in my car and even down to -30 degrees I noticed the care turned over like it normal. Regular oil, even other synthetics I tried, would turn over much harder. Regardless of the numbers, I'll stick with Mobile 1 for my cars and my guns.

 

[Virginian]

The thermal coefficient of expansion for carbon steel is 7.3 x 10 to the minus 6 power inches per inch/degree F. 400 Stainless is about 4.5 x 10 to the minus 6 inches per inch/degree F. That ain't the problem.

 

[herrwalther]

Mil-tec has been the standard for cold weather firearm use in the military that I have used. I have used it in the -30 and -40 range with no lockup or freezing issues.

 

[rcmodel]

The thermal coefficient of expansion for carbon steel is 7.3 x 10 to the minus 6 power inches per inch/degree F. 400 Stainless is about 4.5 x 10 to the minus 6 inches per inch/degree F. That ain't the problem.

+1 This!

I have never heard of an 870 freezing in my life.

And that!

rc

 

[d2wing]

This is really a bogus post, if this guy has no idea of what he is talking about. I live in real cold weather and have never heard of that problem, I have been hunting with 870s for 40 years and in actual freezing temps with no problems. Wind chill has no effect on guns. He has no idea what wind chills of -85 or even -20 would be like. I do. He would not be hunting pheasants for sure.
He possibly could have dirt in the bolt that forms a crud that is worse with cold temps. But hard to say what conditions are in that world.

 

[AI&P Tactical]

Ditto to what d2wing said.

 

[gpb]

Thank heavens for the internet. Without it I wouldn't know that guns I have used without problems for decades are prone to all kinds of problems that I have never experienced.

 

[marcclarke]

I use Mobile 1 synthetic on all my firearms. Mobile 1 thickens at a much colder temperature than regular oils. I would suspect if you lube your weapons with it you won't have to worry about the cold.

I use Mobil-1 0W-40 in my car. Yes, there is such a thing as a "0W" oil It ought to flow very well at low temperatures.

 

[stressed]

Many firearms will freeze up at that temp; there are tons of Korean war tales of Garands, 1911's and Carbines freezing during engagements; in some cases they were urinated on to unlock their actions. All of these have longer firing pins than the hammer guns do so that explanation makes sense, especially if the oil on the firing pin and hammer area freezes up.

My South Dakota buddies use dry lube on their bolt guns, as these will also freeze shut on them.

Same issue the Germans had after invading the Soviet Union. the weapons failed and the lube gunked up. MP40 held strong due to fixed firing pin and bolt slamming forward and could be run with minimal to no lube. Soviet weapons fared far better.

Never heard of this with the 870. Use dry lube.

 

[ugaarguy]

This one has run its course.