Original german finish bluing question?

[K98sniper]

Hello,
Looking to blue MP40 magazine. What type of bluing was used during wartime?
What is accurate? Can it be done?

Anyone have a good reference for bluing? Seem to not find any information online on how the Germans blued their parts and weapons.

[me6_130]

I use potassium nitrate (300g)+ custic soda (1000g) in 1L of water. It gives a good blueing. If interested PM me and I'll let you know all the process.


Carles

[K98sniper]

Sent you a PM. Yes please let me know

[me6_130]

Sent you a PM. Yes please let me know

Yes, seem your PM. Let me have a while to write the whole process. I might post it here directly, as another member was interested, and might help more members.


Carles

[andundiek]

Please post it here as I'm also interested in a good "how to blue"

[K98sniper]

Yes, today preferably

[me6_130]

Yes, today preferably

Ok, but I've needed some time for your safety...and I've also got to work and a family to take care of.


Carles

[me6_130]

Ok, There it goes. Perhaps this thread should be moved to the Conservation/Safe Keeping Forum.

I learnt this method from a weapon magazine many years ago and used it several times with a great result. Now, BE CAREFUL, use rubber gloves and protective clothes and goggles as these chemicals might burn your skin and fumes are toxic, so if you do it in your kitchen make sure there is a good ventilation (AND YOUR WIFE ISN'T AT HOME!!!). I am not responsible for any accident that may occur if you are not careful. Make sure you dispose the leftovers of the chemicals properly once you finish.

There are some variations and tips at the end. Read everything before you start buying and mixing stuff.

The formula is:
-300g of Potassium Nitrate + 1Kg Sodium Hydroxide (Caustic Soda) per 1 liter of water. Multiply if you need more water

- You will need 2 iron or steel containers to complete the process; 1 for the chemical bath and another for clean water bath. Make sure the containers are well sealed and liquid doesn't spill!!! and your parts fit in them.

- The parts you want to blue should be well clean and degreased. If you want a really nice finish, you can polish them to make them shinny, but take into account what they originally looked like.

- Fill the two containers with water. Put the chemicals into the water of one of the containers while the water is cold, and heat slowly. DO NOT PUT THE CHEMICALS INTO BOILING WATER OR IT WILL BUBBLE AND SPLASH, GETTING YOU BURNED!!

- Both containers should be warmed up till NEARLY boiling point BUT DONNOT make it bubble, keep temperature controled.

-Tie the parts you want to blue with wire, so you can deal with them without touching the chemical bath, or use pliers or other tools to move them.

- Dip the parts in the container with the chemicals for about 15 minutes. Pull out to see if the colour is OK, well blued. If not blued enough, put into the bath again and repeat after a few minutes.

- Once the parts are blued, pull them out of the chemical bath and move them to the second container with warm clean water, for another 15 minutes, to remove unwanted chemicals.

-Pull the parts out of the water bath and clean with fine steel sponge, then dry with a clean cloth and oil with your favorite weapon oil.

End of process.

Variations and tips:

If I can't get Potassium Nitrate, I use Sodium Nitrate and it works the same. Another member has told me the german formula used Ammonium Nitrate, but I have never tried it.

I found that using 300g of nitrate gave me short time to blue all the parts I had, as the chemical bath was worn out, making the last parts greenish, so I used 400g of nitrate.

Hope it helps.

Carles

[andundiek]

Thanks!

Perhaps one day.....when my girlfriend isn't at home....

[jonathanseverin]

Hey Carles,
Great information, could you post some pictures of your handy work?
Jonathan.

[me6_130]

Well, these are old pics (about 20 years ago)...but I blued the MG with the red arrows...and the MP in the second pic. This last one was recovered from scrap, slightly rusted, so looks a bit pitted but colour of both is quite good.

Carles

[jonathanseverin]

Thanks Carles,
Great results, it works very well.
Jonathan.

[August]

Excellent information!
Thanks for taking the time to write it out.
I'll share this with my buddies who would like to do this sort of thing.

[me6_130]

Excellent information!
Thanks for taking the time to write it out.
I'll share this with my buddies who would like to do this sort of thing.

You're welcome.


I forgot to mention I didn't remove the remains of older blueing of that MG34. I only removed grease and rust spots. I did remove almost all finish on the MP as it was slightly rusted on all the surface.

Carles

[K98sniper]

Do you know where to get purified ammonium nitrate?

Where are good sources?