Easiest HPA Systems to Install

Airsoft can be a very competitive sport, and players are always trying to gain an edge over their opponents. HPA or high-pressure air systems improve the performance of airsoft guns and are a definite advantage when in the field.

In this article, we’ll show which HPA systems are available on the market and which of them are the easiest to install. We’ll also provide a basic installation guide along with some tips on using the HPA system.

What Is HPA, and How Does It Compare to GBB and AEG?

HPA, as the name suggests, uses highly pressurized air to fire ammunition out of an airsoft gun. It’s similar to GBBs or Gas Blowbacks except for the actual gas used as fuel. HPAs are superior to GBBs in performance as temperature changes don’t affect pressurized air; meanwhile, GBBs usually operate worse when colder.

AEGs or automatic electric guns usually have lower FPS than HPAs as voltage limits the speed of an AEGs launch mechanism. Most AEGs come at seven to nine volts by default, and it takes a highly modified internal system to withstand an 11-volt battery. The speed of an HPA system can be adjusted via the air canister and needs minimum adjustments in the gun’s internal system once it’s been set up.

What Are the Easiest HPA Systems to Install?

Below are some of the more popular HPA systems in the market and what they offer to the airsoft enthusiast.

Click the links below to jump to a particular brand

Polarstar

Redline

Wolverine

Daytona

The Most Beginner Friendly Kit

Considering all the kits presented above, the easiest HPA system for beginners would be the Polarstar Fusion Engine. Many of Polarstar’s products are very simple to install, but the Fusion Engine as a full gearbox replacement is the most straightforward. Users don’t need to tinker with the triggering mechanisms or remember tubing placement. Just remove the entirety of your old gearbox, then replace it with the HPA kit.

Steps to Install a Drop-In HPA

If you want a more versatile HPA system, you might want to try a drop-in kit instead of a gearbox replacement. Although not all HPAs are created equal, most drop-in conversion kits are made similar to each other as they need to fit the standard gearbox. The following are the usual steps required when converting an AEG rifle into an HPA system.

• Take out the gearbox from the gun.

Remove the screws holding the two halves of the gun together on the outside of your AEG. Inside, you should find a container with wiring running out of it. This is the gearbox. Remove any screws holding the gearbox in place, if any, then pull it out from the gun’s body.

• Open the gearbox.

Remove the screws that are holding the gearbox closed. Remember to separate these screws from the ones used for the cover of the gun.

• Remove everything inside the gearbox.

You’ll only need the gearbox casing itself for a drop-in HPA. The spring, gears, and piston won’t be necessary, so take them out. You will need to keep the trigger, and the buffer tube, so set them aside for later.

• Install the trigger board.

Your HPA system should come with a trigger board. It will look like a small circuit board, and it controls the output of the HPA system. Place the board where your original trigger mechanism was located. Screw the board in place.

• Place the HPA module in the gearbox.

The module should be placed where the piston was originally in the gearbox. Make sure that it’s appropriately aligned before proceeding.

• Connect the module to the trigger board.

Refer to the manual of your HPA system to locate which wire connects to the trigger board. The wire should click onto the board.

• Connect the wiring harness.

Your HPA system should come with another wire that slots onto the trigger board. If your model doesn’t have one, your particular HPA might not need an FCU. In that case, skip this step.

• Position the air tube and wiring harness.

The air tube should normally bend down in the direction of the grip, but if you plan to run the tubing onto the gun’s stock, adjust the position of the air tube as required.

• Put the trigger back in.

Place the trigger in the same place where you removed it. Give the trigger a few pulls to see if it’s properly aligned.

• Put the buffer tube back in.

The tube should face the HPA unit.

• Close the gearbox.

Make sure that all the proper screws are replaced to their original positions.

• Install the gearbox back onto the gun.

So now that you’ve familiarized yourself with the HPA system, you should consider the pros and cons of getting one yourself. Here are some quick advantages and disadvantages of an HPA.

PROS

Very Stable Performance

Each round fired does not lose speed compared to AEGs and Gas blowbacks. The constant FPS means that any adjustments made to the hop-up will stay consistent throughout the game’s entirety. If you want a gun that maintains accuracy for an extended period, then an HPA might be for you.

Quick FPS Adjustment

Adjusting the FPS on an HPA requires only turning the regulator on the air tank or the built-in regulators for models that use them. Note that some fields require tournament locks on HPA tanks to prevent adjustments while in-game. This is mainly used to keep players from cheating by exceeding maximum FPS limits.

Basic HPAs Have the Same Performance as High-Level AEGs

Even the most basic HPA systems can produce the performance quality of expensive AEG builds. Increasing the FPS on a battery-operated gun requires extensive modifications of the interior.

Silent Operation

Unlike AEGs and gas blowbacks, an HOA gun produces very little noise while firing. This is an advantage if you don’t want to give up your position when hiding from opponents. However, it’s a disadvantage if your objective is to provide suppressing fire for your teammates.

Suppressing fire usually requires that your opponents hear the loud bursts of your gun, so they keep their heads down and allow your team to move. If you’re sniping, however, this is a very big advantage.

Minimal Maintenance

HPA systems usually have very robust builds and require very little maintenance. As they don’t have too many moving parts, a quick clean-up now and then is all that’s needed to keep it in top shape.

CONS

Relatively Expensive

HPA systems present a steep upfront investment and require you to disassemble your current hardware. Even basic systems can cost the price of a new AEG. If you only play casually, getting an HPA system may not be worth the asking price.

Not Allowed on Some Fields

Because of the ease of adjusting the FPS, some fields don’t allow HPAs in their games. Although tournament locks alleviate this somewhat, some harmful stigmas remain about the system itself. Until proper regulation on FPS adjustment becomes standardized, expect a few fields to deny entry to HPA guns.

Tank Transport Can Be Inconvenient

As an HPA user, you’ll need to lug a tank along to play. This is fine for short games, but some MilSims can last for days, and bringing multiple tanks can become tiresome. Several backpacks alleviate this somewhat, and hydration packs have become a standard for multi-day events.

Air Hoses Can Get Stuck During Outdoor Play

Another disadvantage of an HPA gun is that your air hose can get stuck to branches or corners whether you’re playing indoors or outdoors. The only solution to this is to be aware of your surroundings and never turn too quickly unless you’re sure your air hose is safe.

If you’re using an HPA system, here are a few tips that you should keep in mind:

1. Never put oil or grease on your tank’s fill valve. The tank does not require lubrication, and oil or grease can cause the tank to combust during refill.
2. Hydro-test your tank every so often to check for leaks. Your tank should have a recommended date for hydro-testing.
3. Store your tanks in a cool and secure place. When traveling, make sure that the tank doesn’t move around unnecessarily.
4. Turn off the tank and allow the air to bleed out when not in use. This eases the pressure on the tank and increases its longevity.

Although HPA systems are quite the investment, they can significantly improve the performance of your airsoft gun. Although not all HPAs are easy to set up, some systems only involve quick alterations to the gearbox. Hopefully, you’ll find this list of the easiest HPA Systems helpful to help you start on your modding journey.