Brass swelling up from cold weather

[Jluck]

It is a tight chamber but so far have had no issues up to this point, Only have 130 grain Swifts moving 2855 at muzzle. so have not experienced pressure signs.

This doesn't answer the question. Did you try your manufactured (not reloads) ammunition in said rifle before being in the field? Did it cycle correctly?

 

[Unoboats]

I did and no issues as did the reloads after a few minutes inside the shop.

 

[epoletna]

I'm guessing it's a neck issue. The chamber and barrel contracted slightly, and your tight neck prevented the cartridge from going into the chamber. You might find you need to turn the necks slightly to have them go into the chamber in very cold weather.

 

[Mike Matteson]

I was with a older man at the time hunting in Col. It was -20 in the early morning time period. He had taken his bolt apart night before and oil it and put it back together. He place the rifle outside that night to boot. When he tried to fire the rifle that morning at an elk the rifle wouldn't work. As near as I could figure the firing pin was frozen inside the bolt. We took the round out of the chamber and tried dry firing the rifle several time. Finally the firing pin worked.

 

[Unoboats]

I'm guessing it's a neck issue. The chamber and barrel contracted slightly, and your tight neck prevented the cartridge from going into the chamber. You might find you need to turn the necks slightly to have them go into the chamber in very cold weather.

It was frost built up in the chamber. My bad in leaving it in the truck for the later part of the season with all the extreme temp. changes. Reproduced it this morning. Have plans to bump shoulders back 3-4 thousands to hopefully eliminate issues later.

 

[Dean2]

We hunt a lot in very cold weather. Bolts are lubed with powdered graphite, as are triggers. Bore and chamber get a real light swipe of Hoppes 9, it does not thicken even at -50. Once a hunt starts, guns are left in the cold, never brought into the heat as all that does it produce condensation that turns to ice or frost when you take it outside again.

Extra ammo is stored where it is warm, ammo in use goes in your pants pocket. Guns are carried empty in or on vehicles, only loaded when you are on foot or in a stand. Ammo removed from a gun after a sit or walk goes into a cartridge sock on the guns butt and stays with the rifle in the cold. It is used from then on until it is fired. Ammo also never goes from -40 to a warm room due to the same condensation problems, but to be honest we have never had a problem with ammo that got cold and them warm, even multiple times.

All ammo is test fitted with the gun at the cold operating temp. Your problem seems likely to be ice or frost in the rifles chamber.

 

[Unoboats]

We hunt a lot in very cold weather. Bolts are lubed with powdered graphite, as are triggers. Bore and chamber get a real light swipe of Hoppes 9, it does not thicken even at -50. Once a hunt starts, guns are left in the cold, never brought into the heat as all that does it produce condensation that turns to ice or frost when you take it outside again.

Extra ammo is stored where it is warm, ammo in use goes in your pants pocket. Guns are carried empty in or on vehicles, only loaded when you are on foot or in a stand. Ammo removed from a gun after a sit or walk goes into a cartridge sock on the guns butt and stays with the rifle in the cold. It is used from then on until it is fired. Ammo also never goes from -40 to a warm room due to the same condensation problems, but to be honest we have never had a problem with ammo that got cold and them warm, even multiple times.

All ammo is test fitted with the gun at the cold operating temp. Your problem seems likely to be ice or frost in the rifles chamber.

Thanks for the reply Dean

 

[cohunt]

yes, the chamber in a steel barrel does contract when cold (and expand/get larger when hot)--- BUT the thermal expansion of brass( and copper and lead) is greater than that of steel so that means that the brass case actually contracts faster/more than the steel chamber --- as noted, it was probably a frost/condensation issue

 

[Dmagna]

Had a first time for me on this subject. My 6.5x284 loaded in lapua brass would not allow the bolt to close till the bullet warmed up a couple minutes. I understand metals will expand in cold weather, but it never got below 35 degrees last night and the shells were under the bolt in a case. inside my truck.
Need some coaching on this one. been reloading my ammo since 1968 and this is a first for me.
Chip

Metals do not expand when cold, they contract.

 

[Irish Neil]

In the days of sail iron cannon balls were stored in a pyramid on a frame fixed to the ships deck. The frame was made of brass and called a "monkey". Sailors described extremely cold weather as " cold enough to freeze the (cannon) balls off a brass monkey"...brass contracts more than iron as temperature decreases. I think the phenomena is described scientifically as the coefficient of expansion but it's a long time since I studied the subject.
Modern brass may not be brass as it was traditionally constructed but an alloy that does not have the same characteristics.

 

[Unoboats]

Metals do not expand when cold, they contract.

If you read back I corrected myself , I had a brain fart and said expand vs contract. So my Chemistry/Biology double major in college was a waste of time I guess. LOL. But I hope you correcting me before seeing the whole thread makes you feel important. Because just being critical vs being helpful makes your response to this thread worthless.
But thanks for caring.

 

[Dmagna]

If you read back I corrected myself , I had a brain fart and said expand vs contract. So my Chemistry/Biology double major in college was a waste of time I guess. LOL. But I hope you correcting me before seeing the whole thread makes you feel important. Because just being critical vs being helpful makes your response to this thread worthless.
But thanks for caring.

Well the 6.5x284 is a picky cartridge, what is your measured neck size? I use a Redding die fl die with a .292 bushing.

 

[Unoboats]

Well the 6.5x284 is a picky cartridge, what is your measured neck size? I use a Redding die fl die with a .292 bushing.

Myself as well

 

[cowboy]

It was frost built up in the chamber. My bad in leaving it in the truck for the later part of the season with all the extreme temp. changes. Reproduced it this morning. Have plans to bump shoulders back 3-4 thousands to hopefully eliminate issues later.

Good for you in staying with it. Now you know. Somehow it is always better and the knowledge lasts longer if you prove it yourself.