***Posted by jim***
Hi Cerwyn,

As you have the tips for using the modelgun rounds - now I've problems with some of my cartridges - such as:

After firing the rounds (I know I shouldn't have - but I was tempted) the rounds oxidised and turned dark - I want to make it shiny again...some Japanese-made solvent can solve the problem but is there another way to solve this problem?

Also,

What can I do to polish old rounds like this...is it OK to use a tumbler with stones (just like treating the brass shells before handloading live ammo)?

Any Mr Handyman out there who can join solving these problems...will be greatly appreciated...

***Post by Claymore***

Jim i would look at soaking in viniger and bicarbonate soda for a well then wipe over with wire wool which should take the oxidising off then for the shine as you metion the tumbler used for shining up real brass rounds should do the trick

Hi Jim,

I've found an Ultra Sonic cleaner perfect for washing brass cartridges after each firing and then a polish in a Vibrating Tumble polishing machine.

I am in the process of writing up a Guide to... Cleaning and Restoring cartridges now but have a look at this photo...



These are P220 MGC cartridges complete with pistons and primers. They've just had 3 hours tumbling in my polisher and then sieved out of the polishing compound in a kitchen collander.

They come out beautifully shiny and the o-rings don't get damaged either as the medium used for polishing is a ground up walnut husk based material that doesn't scratch.

Given long enough in the polisher, even inside the cartridge is cleaned and polished too.

I'll sort out the Guide asap.

Cerwyn

***Post by Madmike***


You can polish the outer surface by using a metal / chromium polish paste and a cloth. This polish paste is often used for chromium parts on cars and won't damage your carts, but it is almost impossible to polish carts inside ... I got nice results for the outer surface, but it means quite a lot of work, the right thing to do while watching a boring movie or TV show.

One way to polish inside cartridges is with a mascara brush (see the posts on Loading Marushin / MGC cartridges).
The brush used with metal polish can help to restore the surface but as MadMike says, it's a long and tedious job if you've a lot of them

The Lyman type Tumble Polisher does a pretty good of cleaning both outside and inside surfaces but it is worth ensuring that the cartridges are washed first with an UltraSonic cleaner or other methods.

Most important tip of all is to clean every cartridge after every shooting session.



Cerwyn

Hiya ricks,

Well I guess a Dremel might help but I don't think I'd want to be holding onto a little brass tube with a rotary brush doing 20,000 rpm in it
Burnt fingers come to mind as well as flying cartridges...

If the rotary brush was too abrasive it might even remove too much brass from the bore leading to a loss of gas seal between the cap & bore or the piston o-ring & bore.

Cerwyn

***Posted by ricks***


There are some heavy felt tips available and - maybe - a brush or two. The model I have will throttle down to next to nothing...

I guess no one needs yet another way to burn his fingers with this hobby.

FWIW, Nevr-Dull might be put around the end of a stick or broken drill bit & used manually or - for the daring - with a rotary tool.
Here's their website:

http://www.nevrdull.com/

Rick

Another idea I've tried recently: "Cif Cream" (in some countries I've seen it named "Jif"). It is normally used to clean/polish kitchen stuff, but experiment showed that it easily cleans brass from oxidation and other surface issues.
I put a drop of Cif Cream on cartridge and gently rub it (with bare hands, gloves, piece of paper...) on surface.
Using this method I have restored some old, used cartridges that I got uncleaned, dirty and discolored. Ultrasonic cleaner helped in the beginning, but couldn't remove most of "coating". I do not have a tumble polisher, so I have tried Cif Cream, as described.

In long term this may probably remove tiny amounts of brass from cartridges, slightly changing their dimensions.