MP5 - submachine fun

This is the first made LaBr-gun for HomeLESS project. It is easy to build but not so sophisticated like others. But is useful for understanding for basic principles how to make the others.


Electrical parts:

- microswitch ON-ON.

- condenser, with 1800μF and 6.3V but voltage is not critical (less voltage is better because of size).

- LASER module, ML-SHW-650-05-D or something like that. This type has a resistor inside.

- wires, blue and red colors are recomended.

Capacitance of the capacitor depends on the supply voltage and the laser module. For supply voltage about 2.8 volts (two full rechargeable battery) is good start with 1800μF. Maybe you need to buy more capacitors with different capacitance and try it one by one.

Before you start modify the airsoft replice, be sure that your configuration of electrical parts works fine. Make prototype first, see Control electronics page.

Keep in mind that the used capacitor needs proper polarity.


First step

You have to disassemble the airsoft replica to determine places of control electronics. You may need to modify the internal configuration (remove some parts) to get place for electronics.


Battery holder

This is the hardest part. You have to decide which place is the best for battery pack. The right place depends on the type airsoft replica.

Remember that battery pack must be easily accessible for replacing batteries.

For this replica is best place for batteries inside of weapon light. (That is the reason for I choose this type of MP5). Now it is needed to modify it.  Modifying by hand tools (knife, soldering station, duct tape, etc.) it is depend on your own mind. For inspiration look at the pictures below.

Good result means easy access for replacing the battery.


Trigger modification

You need to properly set up microswitch to trigger mechanism can activated the LASER module. Look at the pictures they are better than a thousand words.

Final check of electronics

Now you have to set properly wires to fit the contacts on    schematics     on page Control eletronic.

Keep in mind that the used capacitor needs proper polarity.


LASER module

In this LaBr-gun is LASER module inserted into replica instead of barrel. This is simple solution but there is no way how to adjust the LASER module to fit with sights.



Because the LASER module cannot be easily adjusted we have to find another way how to do it. The answer is use the additional sights. At this case is used collimator for MP5 guns (replica for airsoft replica). This solution works fine.


After you made it all it is time for testing. The best test is by the public. If you worked well, the people appreciate it.