How long until cold welding occurs?

[Idaho-Lefty]

THIS ^^^ would Be, my Guess also !
Kinda was thinking,.. 3 years, 4 Month's, 7 Days, 45 minutes, tho ! ( Just, a Little,.. LONGER ! )

 

[10XSHOOTER]

If you look at Military loaded ammo from the 50's to 70's.
There is a black tar sealant on the bullets.
this was to prevent the Galvanic welding of the bullet to the case
Allows the ammo to be stored for Many years

 

[ShtrRdy]

Why does the shoulder part of that case not look like brass?

It's new brass that has an anneal color to the neck and shoulder.

 

[markm87]

If you look at Military loaded ammo from the 50's to 70's.
There is a black tar sealant on the bullets.
this was to prevent the Galvanic welding of the bullet to the case
Allows the ammo to be stored for Many years

This is still used on a lot of current ammo. Most of us assumed it was to keep the propellant dry if the round got wet.

I've only felt the crack when decapping brass that sat out in the elements for a long time and got wet. The primer cups sometimes seem to fuse to the pocket walls.

 

[fatelvis]

Since I LEAVE, a Little bit of, Carbon "Soot" and Plastic Brush, the Neck's insides with, Hornady's waxy Unique Lube,. THIS Cold weld, Chit, has NEVER Been, an "issue" for Me, since Boyhood, Mid 1960's,..
when, I started Reloading.
I've Had, NO issues with, 20 to, 30 Year Old,.. Hunting, Ammo.
I would NEVER, ever, "Deep Clean", a cartridge "Neck",.. Shtr Rdy,.. IS,.. Bang "On" !!!
How Long it Takes to, "Cold Weld" I have NO idea and DON'T care, as it's NEVER Been, an issue for, Me !

Thank you for your response. Let me ask… have you EVER loaded VIRGIN brass? I usually leave carbon in the neck also, but right now I am loading several hundred virgin cases, and the cold Weld situation has me concerned, if I don’t fire them for an extended period of time.

 

[Idaho-Lefty]

Thank you for your response. Let me ask… have you EVER loaded VIRGIN brass? I usually leave carbon in the neck also, but right now I am loading several hundred virgin cases, and the cold Weld situation has me concerned, if I don’t fire them for an extended period of time.

I use, a tiny Bit of Hornady Unique Lube on a Plastic Brush, ( 3-4 strokes, in each ) on Virgin Brass and I won't wait, 5 years to Shoot them, up ( just in Case ),.. LOL ! The Carbon "Soot" / Unique Lube, works,.. BEST !

 

[Fire Dog]

Why does the shoulder part of that case not look like brass?

Just discoloured due to annealing… You would see that effect on any factory ammo even the stuff that is factory polished on the outside if you opened one.

 

[c3d4b2]

I have seen cold welding performed to seal electronic cases.

This article does a decent job explaining the process.

Cold Welding: Welding in Space, Pros and Cons of Cold Welding

This article will discuss cold welding in space, cold weld aluminum and other metals, cold welding with TIG, and related topics.

workshopinsider.com

Here is a link that offers anouther possibility

How do metals in contact fuse together?

A threaded brass plug screwed into a threaded brass coupling will corrode and become fused together when subjected to warm humid air and undisturbed for a long period of time (10 or 20 years). Since corrosion removes metal, how is it that the plug cannot be removed after it apparently corrodes...

www.eng-tips.com

 

[ELR LVR]

Why does the shoulder part of that case not look like brass?

Heat Bluing from the annealing process

 

[Fire Dog]

Thank you for your response. Let me ask… have you EVER loaded VIRGIN brass? I usually leave carbon in the neck also, but right now I am loading several hundred virgin cases, and the cold Weld situation has me concerned, if I don’t fire them for an extended period of time.

Neolube #2 can be your friend… or just mix up some Micro-fine door lock graphite with a bit of Isopropyl alcohol {much cheaper} and apply a light coating to the inside of the case neck.. Easy on the mandreling and seating and I am guessing will never let a “weld” situation occur.
It is a dry lube {when the alcohol evaporates} unlike the suggested Hornaday Unique Lube or any other lube that is not a “dry” lube and you will find that though it may work, it will stick granules of powder to the case neck as you fill the case.
Yes, I have loaded lots of “Virgin” brass and never had a problem.