Why a HPA System Might Be for You Part-1

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hpa airsoft gun system
Category: Tips

Why an HPA System Might Be for You. HPA is an acronym for High-Pressure Air and is an alternative solution to power your airsoft guns. Gaining traction through companies such as Polarstar, HPA systems might not actually be as ‘new’ as you think. During the early years of what we now call airsoft, our airsoft guns were powered in a similar way to the HPA systems of today.

Unlike most gas-powered airsoft guns on the market that feature internal gas cartridges or canisters (often housed within the gun’s magazines), HPA systems are powered by external canisters of pressurised air, very akin to paintball guns. These large, external canisters provide HPA systems with quite a bit more power than traditional gas rifles, allowing for a multitude of performance enhancements that are not seen with conventional gas systems.

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HPA systems are unique gas systems which have a lot of advantages as well as disadvantages. While the above might paint HPA systems as the dominant choice within airsoft, there are a number of drawbacks associated with the systems, which we will address later. However, for now, just look at HPA systems as an airsoft rifle that is traditionally powered by an external canister of pressurised air. That said, newer systems are emerging on the market that allow HPA systems to be used in conjunction with Co2 cartridges or a tank which attaches directly to your airsoft gun.


AEGs and HPA guns work making use of the same idea — essentially both make use of pressurised air to accelerate BBs through the barrel. However, in an AEG, this pressurisation is created within the gun before each shot via a mechanical system. In an HPA gun, pressurised air is stored in an external canister and delivered to the gun with each pull of the trigger rather than relying on a mechanical process to create pressurised air within the gun itself.


High FPS – The adjustability of HPA airsoft guns can make them the most powerful of all airsoft gun types, meaning that they can deliver the highest possible FPS in the easiest way. This is done by controlling the air pressure’s PSI. The higher the PSI (air pressure) the higher the FPS can be. High FPS means that your shots will be more accurate at longer ranges as each BB will be able to fly through the air with more energy behind them.

FPS Consistency – HPA airsoft guns also offer more consistent FPS between shots. This is achieved using either an electronic circuit board that actuates a valve or, in the case of the pneumatic systems, a pressurised valve that can be manually opened and closed with the pull of a trigger (as seen in fully mechanical HPA guns). This high degree of consistency comes from the gun only allowing the same volume of air into an expansion chamber that then pushes out the BB.

Faster Rate of Fire – In addition to offering higher FPS, the increased power that HPA guns provide also means that they can provide faster rates of full-auto fire. This can also be adjusted using electronics as well as some brands facilitate this kind of rate of fire adjustment without having to increase the overall power of your gun. However, these systems are usually slightly more pricey.

Adjustable FPS – If you’ve ever wondered how to lower FPS, just know that an HPA gun makes this process relatively straightforward and simple. As previously stated, HPA guns offer adjustable FPS and while it may seem like being able to lower the FPS of your gun wouldn’t be much of a benefit compared to increasing it, some airsoft fields have FPS limits in place and will require you to lower the FPS of your HPA gun before they allow you to use it. With HPA guns, you usually just need to simply lower the PSI coming out of your air tank, and you are done. No disassembly required.

Simpler Internal Design – Compared to AEGs, HPA airsoft guns don’t have nearly as many moving parts. This makes HPA guns a little more reliable and less likely to malfunction. HPA guns revolve around their engines and as long as you have installed everything correctly, you will have to deal with little to nothing.

Quieter – The “noise” we get from airsoft guns is from their mechanisms working. For electric AEGs, that’s the sound of the gears, piston, and cylinders moving to produce the necessary air pressure for the BB to be fired. For gas guns like GBBRs, the sound will be from the bolt carrier group, trigger, and expansion of gases in the gun. Even though HPA guns are the most powerful type of airsoft gun, they are also among the quietest.


Weight – If you run a traditional HPA set-up, which includes an external tank and line, the external canisters of pressurised air that attach to HPA guns are quite bulky and will increase the weight of the load you will need to carry on your person by a substantial amount.

Cost – On average, an HPA set-up will be more expensive than buying others such as AEGs or GBBRs. This is due to the fact that many popular HPA systems require a donor gun before you can turn it into a dedicated HPA airsoft gun.

Aesthetics and Realism – One of the biggest draws of airsoft is the fact that the guns and gear look so realistic, and many airsoft players enjoy the realism of the sport as much as the action that it offers. Having a gun that features a bulky air tank attached or an air line that runs out of it takes away a lot of this realism. By the same token, the fact that HPA airsoft guns can fire at much faster rates than even real full-auto weapons again detracts from the realism of the sport.


Rest assured, though, that HPA doesn’t have to have all of the drawbacks mentioned above. In fact, we have just started stocking WE’s brilliant conversion system, something we will be taking a look at in our next blog! So if you think HPA might be the route you want to go, but you don’t want to have to remortgage your house, then tune back in soon for our look at WE’s HPA conversion system! You can see all of our airsoft HPA air systems and parts on our website.


You can see our full range of airsoft guns on the Just BB Guns category product pages. We also have a large number of BBs and airsoft accessories, all at great low prices.

Address: Just BB Guns, Trimex House, Pier Road, Feltham, TW14 0TW
Call us now: 0330 900 5224
E-mail Address: [email protected]
Website: www.justbbguns.co.uk

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