Bolster Armouries: How to Maintain your AEG

Bolster Armouries: How to Maintain your AEG

The Bolster Armouries ONYX series of AEGs are designed to perform on the very edge of what is possible. A reliable and robust AEG intended to handle both the rigours of an Airsoft skirmish and the surgically precise demands of competitive shooting equally; the ONYX does it all, other than clean itself! 

AEGs like the Bolster Armouries ONYX series are set up to provide extremely high performance in all aspects, but this can only be achieved with proper airsoft AEG maintenance.

The maintenance required to keep your AEG performing at its best includes cleaning the inner barrel and the gun’s external parts. The inner workings of the Bolster Armouries gearbox are very precisely set up and should only require reapplication of lubricant by the Bolster Armouries team when the AEG is returned for a service and health check.

Cleaning the inner barrel, and external parts are all you will need to do yourself to keep your Bolster AEG doing its thing, so let's take a look at exactly what you will need to do to keep your Bolster Armouries AEG shooting to its full potential:


Cleaning your AEG's Inner barrel

Inside the Bolster Armouries ONYX, we are treated to some of the finest HOP and barrel components available to Airsofters anywhere. The use of a Prometheus 6.03 Stainless steel tightbore inner barrel, coupled with a Maple Leaf OMEGA flat HOP nub requires slightly more frequent maintenance to be carried out to get the best possible performance. The Prometheus inner barrel is of a tighter bore than the average and relies on its extremely high polished internal surfaces to provide the superb accuracy this barrel is known for. The OMEGA nub provides an extremely wide contract area and also provides a greater HOP effect, though the balancing factor is that if maintenance is neglected on either of these two components your AEG is more likely to jam, rather than just performing poorly. This is due to the tight tolerances within which are required for the exceptional accuracy inherent in this barrel/HOP setup. 

What you will need to clean your inner barrel

  • Airsoft approved degreasing spray
  • A polymer Airsoft inner barrel cleaning rod 
  • Microfibre cloth
  • A pair of scissors

Do NOT use

  • WD 40 or any lubricant which is not intended for Airsoft
  • A metal cleaning rod for an Air rifle or similar
  • Kitchen towel or similar 

Step 1: Unload and disconnect your AEG's battery

Firstly, ensure your AEG is unloaded by removing the magazine, inverting the AEG, and firing two shots on semi-automatic in a safe direction whilst wearing eye protection to clear any BBs retained inside the HOP unit. With this done, disconnect your battery. With your battery disconnected, dial your HOP-up unit down to its lowest possible setting. 

Step 2: Prepare your barrel cleaning cloth

Next, cut the microfibre cloth into strips to fit your cleaning rod. These are generally sized to fit a piece of cloth measuring 10mm x 40mm, though this will depend on the thickness of your chosen microfibre cloth. You will probably need 3 or 4 strips of cloth, but we advise you to continue to clean the inner barrel until the last cloth piece comes out clean, so having one or two extra might save time later. 

Insert one of your strips of microfibre cloth into the slot on your cleaning rod, and wrap it around so it barely fits inside the inner barrel. It is helpful to have your scissors handy in case you need to adjust the length of the cloth strip for a good fit. With your cloth strip in place, spray a small amount of degreaser onto your microfibre cloth.

Step 3: Swab the Inner barrel 

With the previous steps complete you can now proceed to swab the inner barrel with your cleaning rod, taking care not to push the cleaning rod through the HOP unit. You should feel some slight resistance once the rod reaches the HOP unit, do NOT push the rod any further than this as it could damage the HOP rubber and nub. Remove the old cloth piece and add a new one to your cleaning rod. Repeat this process unit the cloth comes out clean, applying additional degreasing spray when needed. The final pass with a cleaning rod should be done with no additional degreaser, as this will help remove any excess which remains inside the barrel. 

Step 4: Clear out the remaining degreaser 

Following this, we recommend firing a few hundred BBs through your AEG to clear out any remaining degreaser from the inner barrel and HOP unit. Once this has been done, your AEG should have a nice clean inner barrel and be performing to its full potential. Don't forget to set your HOP again after this process!


So, that's it! This is all you will need to do yourself to keep your Bolster Armouries AEG performing at its best. Any work needed on the gearbox or HOP unit itself should be carried out by a Bolster Armouries Technician and can be arranged through your Bolster Armouries Service Book. Look after your Bolster Armouries AEG, and it will look after you!