1. Detonator Pin and Chamber.
The metal detonator pin is a push fit into the plastic Detonator Chamber. After firing, it will be covered in black sooty deposits and will possibly have wet residue due to the Lithium or Silicone based grease used inside the cartridges.
Simply pull the Pin out of the chamber (1), and then wipe off the majority of the dirt with a rag or paper towel, if stubborn dirt exists this can be removed with Wire Wool.
I usually wash mine with all the cartridges in the UltraSonic cleaner for good measure then Tumble Polish it in the Lyman Polisher.
Ref: Beginners Guide to Cleaning Cartridges: http://www.mp40modelguns.com/forum2/viewtopic.php?t=2293
The chamber needs thorough cleaning to prevent deposits building and clogging it up. A dirty chamber can lead to difficulties extracting and ejecting fired cartridges and subsequent misfires and jams.
A mascara brush is ideal, (3) followed by wiping with a cotton wool bud (Q-Tip). Once the cotton bud is clean, a final wash in the UltraSonic cleaner should have it spotless. Run the mascara brush or cotton bud through the vent holes in the base of the chamber too.
A light spray with WD40 or Silicone Oil will protect both Pin and Chamber. Simply push the pin back into the chamber to locate.
2. Magazine.
If left uncleaned after firing, the magazine will be coated in rusty brown deposits from the smoke created by the caps.
Wipe the top of the magazine thoroughly with a damp rag using a little detergent. Stubborn deposits will come off with a stiff brush (a toothbrush is good).
Wipe the inside of the magazines feed lips (4) and spring loaded carrier. Spray the top of the magazine with a little WD40, Silicone Oil, or Gun Oil allowing some to run down into the magazine body. Periodically, strip the magazine itself by removing the bottom plate, withdraw the spring and cartridge carrier, wipe everything clean (5) then re oil and re-assemble.
3. Barrel.
Wipe inside the barrel with a rag or paper towel (6) especially where the detonator chamber fits and the muzzle.
4. Upper Receiver.
This is basically a simple tube so I tend to use a spray on Gun Oil and a rag for this. Wipe the inside of the receiver along its entire length to remove all traces of old oil, soot, dirt and smoke residue. Wipe the magazine-well thoroughly to remove all traces of dirt.
Wipe the Ejector clean (8), then lightly spray or coat with WD40, Gun Oil or Silicone Oil.
5. Lower Receiver
Wipe the inside surface clean of dirt and residue with an oily rag. Check the trigger mechanism for smooth operation (9) and give the Wire connectors and sear a thorough wipe down. Spray a little Silicone or Gun Oil over the mechanism (10).
6. Bolt and Recoil Spring Tube.
The Bolt assembly is a push fit on the end of the Recoil Spring tube so just needs a pull to remove it (11).
The Recoil Spring is encased in a 3 part telescopic plastic tube and needs no more than a wipe with a rag (12).
The Bolt is probably the most important component in any model gun. We'll discuss inspection in a separate guide and concentrate on cleaning here! Wipe all traces of old oil, soot and dirt from all the bolt's surfaces, paying particular attention to the bolt face(13), the groove that slides over the ejector (14) and the extractor (15).
Once thoroughly cleaned, spray the Bolt assembly with Gun Oil, Silicone Oil or WD40 (16), your MP40 is now ready for reassembly which will be covered in the following guide!
