Can you explain this picture?

[HighriseATX]

 

[chili17]

LOL! I have had to fix coffin mg springs, but never one that bad. Looks like a bad heat treat

 

[medphys]

A little bit of soldering and she'll be good to go.

 

[~Josh]

Where can replacement springs for those mags be had?

 

[Vegas SMG]

There were two different gauges of wire used for coffin mag springs. I believe the thinner guage is prone to breaking in multiple places.

 

[BlackBelt]

Wow. Thats insane.

 

[JohnFreeman]

Clearly, you were operating the magazine using reloads instead of factory ammo!

 

[chili17]

Where can replacement springs for those mags be had?

Never seen any. I have repurposed an uzi mag spring for one, soldered 1 and used a coupling. All seem to be working fine. Looked at winding a few mag springs and does not seem worth it to make the fixture. Wolf wanted a huge order to make them, and they were not cheap either

 

[strobro32]

Come on 50 round ZMAG-S!

 

[Vegas SMG]

And this is what I rarely use my coffin mags these days. Drums are cheap.

 

[saxon]

View attachment 31066

not sure what we are supposed to be looking at but DAM that's a big bite out of that napkin

 

[Dockless55]

Termites?????

 

[JohnFreeman]

Annealing. It's handy!

 

[carpecervisi]

This makes me nervous as hell. Never thought about the springs going tango umbrella and no replacements available.

 

[USMG]

it happens on older mags, the springs become brittle and break. looking at the square shape, an uzi spring may work. send me an email and I can check tomorrow if we have one that I can give you.
Michael@usmachinegun.com

USMACHINEGUN.COM
FFL/SOT

 

[root]

And those mags cost HOW MUCH?

Gonna take more then a couple of coupling to fix that!


Rich

 

[HighriseATX]

Here is the story. I bought a M11A1 with a Lage Max31A mk2 that had been comletely cerakoted including two drums and two coffins. To the best of my memory, I only loaded the coffin with 50 rounds once and about a week later was out shooting. After a few rounds, the mag would not feed (you can guess why). I unloaded the mag and thought I just had a stuck follower. About two months later I took it apart and shot the photo. I contacted the seller just in case he knew something about, he says we he reassembed the springs were not broken. He has a background in metalurgy, he added:

"My guess is that you or someone else attempted to refinish the outside of your other mags without dis-assembly and cured the entire mag in the oven causing this embrittlement to these springs. These 60-70 year old springs are made from a beryllium-copper alloy rather than the more modern silicon steel alloy used in modern magazine springs. These
Cu-Be alloy springs are much more susceptible to heat damage than silicon steel springs."

I've got uzi mags, so I'll experiment to see if they can be repurposed in a coffin. Whenever I get to this I'll update this thread. Don't hold your breath, I've got lots of more fun gun projects in the pipeline.

 

[Vegas SMG]

Yours is not go first report or photo of broken coffin mag springs, but none of the other mags had been refinished. I not convinced high temperatures contributed to the springs breaking.