Mystery Belt Fed Machine Gun Top Cover

[peregrinvs]

I’ve used Evaporust (I have a small can in the garage) and it works well, but from my perspective it is expensive for what it is and doesn’t seem to last as long as the manufacturer implies. I therefore save it for removing rust from small / delicate items and use cheaper rust removal methods for larger or more robust items.

[RCS]

There is a machine gun collector & shooter who goes by the name "Heck in Ohio" who owns a a pair of of MG 81's. Sometimes he posts photos firing these on gunboards

[peregrinvs]

Progress. I started by giving the latch end a soak in Sodium Citrate to clear a patch of clean metal. Then I gave it an overnight electrolysis treatment. There’s some way to go yet, but overall it has worked well. I’m particularly pleased that the maker markings are still clearly legible and I believe they show it is from the left hand gun in a Zwilling mount, made by Wagner u. Co. GmbH of Mühlhausen (gal). Can anything be determined date wise from the 69 747 serial number?

[browningautorifle]

Progress.

Yes, it's coming along.

[peregrinvs]

Yes, it's coming along.

Thank you. I think the law of diminishing returns has hit with the electrolysis so I have finished that and immersed the front half in a bath of Sodium Citrate (pending finding a better container that will take the whole thing whilst minimising wasted volume). It’s bubbling away which hopefully means the remaining rust is being chelated and dissolved.

As you may have guessed, I’m quite enjoying this.

[browningautorifle]

It’s bubbling away

After you'll be wanting to know where the rest is...and wondering what this was doing just a minute before it was separated.

[peregrinvs]

After you'll be wanting to know where the rest is...and wondering what this was doing just a minute before it was separated.

I would imagine it was excavated from a dug dump pit. Most probably in Eastern Europe somewhere. I don’t recall the trader having any other large MG parts on his tables so who knows what became of the rest of it.

Having been reading up on the MG81 (a weapon with which I was not previously familiar) I have learned they were an aircraft gun, but later in the war as the Luftwaffe’s fortunes waned many were converted into ground or AA guns. Having an idea of when it was made might give an indication of probability on whether it was used in an aircraft or not.

I did find this ‘gal’ marked example that was supposedly recovered from an aircraft shot down in 1941:

Deactivated Super Rare Luftwaffe MG81 Machine Gun

I would guess that probably most of the UK’s population of MG81’s are crash relics like the above.

[browningautorifle]

Nice piece, yes the rest was probably just part of wreckage and tossed into the hole.

[stencollector]

Muriatic acid (as used in swimming pools) will remove rust extremely quickly. Neutralize with water and blow dry before it flash rusts. The fumes are a bit harsh, so do it on a windy day outside or use a facemask with an appropriate filter in a large open space. Not recommended for use in an apartment or home.

There may be pitting afterwards, but thats not from the acid, that is the pitting left from the rust process.

[browningautorifle]

Muriatic acid

One of my favorites around here, wondered if it might eat some of this cover but I guess you're right. Steel will take it. Yes the rust just disappears.