A clean gun will operate reliably and will encounter fewer problems associated with feeding, firing, and extraction.
Moreover, a clean gun will hold its value better and will be less subject to the ravages of corrosion over the long term.
You know well the importance of keeping your bolt carrier group and barrel clean.
What about your MP5’s trigger group?
Let this short post shed some insight into that.
Field-Stripping, Removing the Trigger Group
First, clear your weapon. Drop the magazine and open the action. Visually inspect the chamber and action to ensure the ZF-5 is clear before proceeding.
Engage the safety, pull back the charging handle, and check the chamber.
Once you’ve cleared the weapon, replace the charging handle into the forward position.
Remove the takedown pins securing the MP5 trigger group. Remove the forend and the endcap. With the end cap removed, you can remove the entire trigger housing, which contains the pistol grip as well as the MP5 trigger group itself.
To remove the trigger group, you’ll need an Allen key to disengage the trigger group from the housing via the right side of the lever. Turn it counterclockwise to loosen and remove. Then pull the lever out.
Flip the housing over, flip the lever up, pull it out, and set it aside.
At this point, you can pull the MP5 trigger group straight out the top of the trigger housing. Set both the housing and trigger group aside.
For a more cursory cleaning, wipe down the trigger pack with a dry cloth or a microfiber towel. If you’re doing a quick cleaning, you can use compressed air – in the absence of solvent or cleaner – to dislodge any fouling from the assembly.
Pay particular attention to the hammer which is exposed and sticks out of the top of the trigger assembly. This piece of the trigger assembly is highly suspect to fouling and corrosion if not kept clean and well cared for.
After wiping down the trigger assembly, applying a lubricant to the MP5 trigger group can both keep it working fluidly and protect it against corrosion. There is a wide range of lubricants and cleaners that can be used to clean and lubricate the trigger group. Some shooters prefer Tri-Flow Trigger Lubricant Spray, which is easy to apply and highly effective.
With the trigger group removed, take some time to clean out the trigger housing. Inside of the trigger housing is a space where fouling tends to accumulate, and if not cleaned periodically, can gum up the trigger’s works and even accelerate corrosion.
Before reinstalling your trigger group into the trigger housing, use another clean rag to wipe out the inside of the housing.
With the ZF-5 disassembled and field stripped in this manner, now’s also a good time to clean the bolt group and the barrel, too.
After doing so, you can reassemble your trigger group in the reverse order from which you took it apart.
First, reinsert the MP5 trigger group back into the polymer trigger pack housing. Push it down all the way, ensuring the pin holes are aligned. Reinstall the levers, starting with the left side; then line up the right side lever’s screw and tighten it with the Allen key by turning clockwise.
Before completely reassembling, test the trigger for functionality to ensure it works. Then, reassemble the ZF-5 in the reverse order from which you took it apart.
Now, after cleaning your ZF-5, is also a good time to lubricate everything lightly with a thin coat of gun oil. Don’t overdo it, though, as too much oil will serve as a magnet for more fouling and dust, which can accelerate abrasive damage.
Just a light coat to limber up the works and protect against corrosion. Wipe away any excess.
The Importance of Cleaning Your Trigger Groups
Pretty much everyone knows most if not all of the reasons associated with the importance of keeping your gun clean.
Keeping your gun clean will teach you more about the platform, making you a safer, more knowledgeable gun owner.
Of course, keeping a clean gun will also protect its value and minimize the risk of damage due to corrosion, pitting, or other issues associated with fouling.
Naturally, a clean gun will also feed more reliably. Excessive fouling accumulation can hinder extraction as well as the resetting of the action. A dirty gas gun – like a ZF-5 – will not operate reliably if excessively dirty.
But what about the MP5 trigger group, specifically?
While the barrel and action will accumulate the lion’s share of the fouling, each time you pull the trigger, dirty port gas containing fouling and oil gets blasted down into the trigger group.
You’d have to let it get really dirty to notice the effects, but if you let it foul up excessively, it could compromise the operability of the trigger.
So, in a nutshell, don’t let it get that far. You should always clean your ZF-5 after 1,000 rounds (500 if you’re running a suppressor), but when you do, don’t just swab out the bore.
Break it down and clean it entirely, including the trigger.
For more information on cleaning your ZF-5, please consult the previous blog or consult your ZF-5 owner’s manual.
Need a New MP5 Trigger Group?
If you have a ZF-5 or an MP5 that has seen better days and could use some new MP5 parts, good news, you’re in the right place.
We carry a wide range of MP5 parts and accessories that are not only compatible with official German HK MP5 platforms but also the ZF-5 and variants of each, as well as other full-size roller delayed blowback 9mm firearms.
This includes replacement MP5 trigger groups, replacement housings, springs, and other hardware. If you need a few spare parts, check here first.
Also, we carry a wide range of other cross-compatible parts and accessories, including but not limited to mil-spec MP5 barrels, muzzle devices, hardware, springs, pins, bolt carrier groups and components, and much more.
Most of them are cross-compatible between Zenith Firearms, HK MP5 subguns, and other similar roller-delayed blowback firearms.
Contact us if you have any questions about compatibility, at [email protected].