so, you're thinking about going HPA. The Ares V2 HPA Conversion system.

[mightyjebus]

Before going into my findings and thoughts on the Ares HPA conversion, it's worth setting the scene a little.

 

I've been messing around with airsoft (BBwars anyone?) for close to 35 years. My first BB gun was a model kit of a S&W pistol that once built fired 6mm BB's. It lasted a few mags worth before I accidently landed on it while sliding over my mates Ford Capri bonnet while trying to shoot him. I'd probably get arrested nowadays if I tried that in Taunton again.

 

In the following years I've owned pretty much every different style of airsoft replica. Not only every weapon type but also every mechanism that makes them fire. I've still got a GBB smg that takes duster cans that you screw into a hose, PTW's, GBRS, recoils, mosfets, snipers, both spring and gas and any other fad that has popped up.

 

I've never really wanted a HPA replica for a few reasons, 1. it seems a bit of a faff, b, a lot of HPA'rs seem to be running around in lycra with drum mags hanging off a pistol and 3, I'm not much of a scuba diver.

 

This changed when I was at a boot sale recently and someone was flogging a tank and regulator and with the Ares V2 HPA conversion popping up for sale, I thought it might be time to give it a try.

Buying these parts looked to be at least removing some of the faff that I couldn't arsed with. Turns out that wasn't the case but that was nothing to do the the Ares HPA engine. Turns out the regulator I bought was goosed and even after watching a few youtube videos on maintenance, it still was goosed. The tank was at least ok until I tried filling it for the 2nd time and the 1.8k pressure valve blew.

While I'm talking about faff, the filling of the tank is a problem. If you have access to a dive shop or an airsoft shop that offers a refill service then it's not to bad but the other options are, buy the foot pump or buy a compressor. Now I live in Wiltshire and since the sea is very very far away, there are no dive shops (or airsoft shops for that matter). I went for the cheap option and bought the foot pump. I filled the 3000psi tank up to 1000psi, went and lay down for an hour and proceeded to go buy the compressor. If you are old and unfit like me, or young and unfit or young and fit, don't buy the foot pump. Go buy the compressor but make sure you change the filter every fill as they get wet quickly and water inside a compressed bottle is a very bad idea.

So I now had a compressor, HPA engine, air line, knackered regulator and knackered bottle. Thankfully the very helpful DJM94 from these very forums was selling a tank, storm regulator and air hose, which he kindly dropped off at his local airsoft shop for me to collect. I now had everything I needed to set up a HPA gun.

 

My donor AEG was a ARES AM-008BK as I had one sitting in the gun rack. I didn't try to fit it into any other M4 style receiver as I thought I'd try to keep it as Ares intended and fit the HPA engine into one of their replicas. This turned out to surprising easy which was a case of stripping the AEG gearbox out of the AEG and fitting the HPA inside. I had to remove the screw from the bottom the pistol grip for the hose and the only really other annoying thing was the stock tube screw was too short so I had to order a M5x100mm from Amazon to put the whole thing back together. It would have been nice for ARES to include a couple of different sized screws with the HPA engine but sadly they missed this trick.

One other thing I did was add an O ring to the plug that you connect your air line to. You can see the connector I'm talking about in the picture above. Adding the O ring stops you accidently disconnecting this connector when you plug in the air line. The last modification I did was cut off the XT30 connector and run a longer pair of wires with a Deans connector so that I could fit the wire down the stock tube and stick a 11.1v Lipo battery inside. The Ares HPA gearbox has the cutouts in the gearbox shell for this so it's a pretty simple task.

 

So with everything connected, a full tank and flippers and wet suit on it was time to test. 

 

trigger response - fast

rate of fire - 16bb's per second

FPS variation - 1 FPS over 20 shots

accuracy - surprisingly good for a stock hop rubber and inner barrel.

misfeeds - none

problems - none.

Sound - very quiet

 

Overall, this seems like a pretty simple way to get a HPA rifle. The low rate of fire means it's unlikely you will be donning lycra and combat rolling your way through the game zone. The lack of variation in the FPS is very nice, meaning that if your aim is true then shot to shot accuracy should be pretty good.

Cost of the HPA engine is cheap compared to other higher end systems however if you shop abroad you can get it even cheaper (£115 from sixmm opposed to £200 in the UK but warranty will be an issue if bought abroad).

There are other initial costs to consider if you are thinking about going HPA:

compressor £160

Tank £65

airline £21

regulator £70 upwards

Wet suit and flippers are option.

 

final impression. It's a very quick way to get into HPA. I'm unlikely to sell all my other guns and go buy a bunch of lycra but I do see the appeal. Once you get over the faff of filling tanks and have all the bits it becomes just as accessible as an AEG. The consistent FPS and low noise make it nice shooting experience. One 3000psi tank will do about 1000 bb's on the Ares HPA engine so a 2nd tank might be worthwhile having.

 

Now that I've lost my HPA cherry I think my next HPA venture will be the VFC M249 converted to HPA tank and a AEG nutsack. 

[Cannonfodder]

Nice. I wonder if they'll do a V3 version 

[The_Lord_Poncho]

Many thanks for taking the time to write this up - given the low price (and the lack of need to find a donor gearbox) it's something that I’ve been keeping an eye on too. Appreciating that you don't have a reference point in other HPA systems to compare to, nonetheless, does the quality of the components, finishes etc seem OK?

 

Looks like you have it sorted now anyhow, but I've had a good experience with an Aliexpress clone of the Balystik HPR800 regulator (and I believe others have had favourable experiences too) - about £20 with postage.

[mightyjebus]

The quality doesn't seem half bad to be honest. Cheers for the tip on Aliexpress, always handy to have a few spare bits just in case.

[SheriffHD]

I went into the bespoke Airsoft store the other day to look at the engine - they reported it's had great feedback from people buying them, they even had a few rifles that they had put it into highlighting that it'll fit in many other RIFs that aren't Ares but did state that some light modification may be needed.

 

I keep hearing great things about this and honestly it'll be on my buy list 

[Enid_Puceflange]

Nice write up, thanks 👍

[Cannonfodder]

Would this fit a MP5K? I know they don't use a standard v2 gearbox but as I understand it the only difference is that they have a motor cage

Edited March 18 by Cannonfodder

[The_Lord_Poncho]

Well, I've eventually got my own one. Seems to be a slightly updated version  - with a much longer battery wire (rear wired), and terminated already with a deans connector.

 

A quick plug into a tank, and a worrying hissing noise from the box indicating a leak as I turned up the pressure with the reg. As soon as I disconnected, got the pressure up on the regulator first, and reconnected the leak has gone - I put it down to the seals or something not being seated fully, and needing a bit of a 'jolt' of air pressure to rectify. I've not popped it in a gun yet, but it seems nicely functional so far. I can confirm that the control unit needs an 11.1v battery to operate - doesn't function at all on a 7.4.

On 18/03/2025 at 18:32, Cannonfodder said:

Would this fit a MP5K? I know they don't use a standard v2 gearbox but as I understand it the only difference is that they have a motor cage

I thought MP5Ks used a V3 gearbox? In any regard, I was originally considering one of these for a (full fat) MP5 that uses a standard V2 gearbox case. But in the end, decided that it might not work - my logic being that it doesn't seem that the nozzle can be swapped out/nozzle length adjusted - so I think you are stuck with an M4 length nozzle (albeit I'd love for someone to prove me wrong on that). Potentially also a little bit of inventiveness would be needed for the selector plate.