AEA How to make your AEA HP SS great again! 100%

Hi,

Good news for the owners of the AEA HP SS. I have found the actual root cause of all the magazine issues, no guessing.
All the owners of the HP SS semi auto already know by now that all the magazines sooner or later will start misbehaving,
to the point of failure. Constant jamming, popped out spring, chewed up magazine rotor, pellet incompatibilities and so on.
Many were converting them to single action because you would never know what it would do next.

*** Airgun Nation does not condone the use of Air Powered guns for any kind of defense scenario. ***

It all comes down to a single part. The magazine spring.

The design of this semi auto is very wrong. Instead of creating a mechanism were the probe would index the magazine,
they introduced two parameters. The speed that the probe returns after the blowback and the speed that the magazine
rotates the next pellet. They were both variable while emptying the air tube. For proper function, the next pellet should
always be in position before the return of the probe. This synchronization could not be achieved because they used the
wrong spring and the wrong way to keep the spring in place.

Lets assume that you have two magazines, one filled with ten 25 grain pellets and the other with ten 30 grain slugs.
The same spring in the first case should rotate a mass of 250 grain and in the second case a mass of 300 grain.
The rotational speeds will be different and in the second case it might not be able to be fast enough. That's why many
people had much more issues with the slugs.

The solution is to use the correct spring for different types of grains. A spring for lightweight 20 grain pellets a second
for 25 grain and a third for 30 grain. At the end you should have three types of magazines for different pellet weights.

I noticed that, after I saw the following jammed magazine:
View attachment 438221

The pellet was deformed by the probe on the lower part which meant that the probe arrived before the pellet was in position.
To test the assumption, I blocked half the blowback holes inside the shroud and I had way less jams and with the pellets hitting
even lower. I was using 25 grain pellets. My next test was to use 20 grain pellets and I was sure that I would not have any
jams with them, as it happened. So the .25 with the stock spring works fine with 20 grain pellets. We need two more springs.

One with 1.5 times the force and one with 2 times the force. I contacted a local machinist and they made these new springs
to my specifications. In order to show that it was 100% the spring and not something else, I used my first beat up magazine
in which the rotor has been completely chewed up.

View attachment 438222

I installed the new spring and I have lost count how many times I have refilled it !!!
It did not matter what kind of pellet I used, as long as it was in the same weight ballpark.
The stronger spring was only for slugs and it worked as intended. Perfectly.
I did not have a single issue since then! Every time I pulled the trigger the pellet would
travel to the target and the magazine would index to the next position.

A semi auto that you can now trust! I am very happy for that, because in all other
aspects, the HP SS is excellent. Design, portability, leaks, power, etc.

In summary, this is what you have to do for a dependable AEA HP SS:

- Replace the valve pin with the enhanced version that its selling on ebay.
- Lubricate all mechanical parts, metal to metal with molybdenium grease.
- Clean and lubricate the magazine with silicone oil.
- Use the stock spring for 20 grain pellets and stronger springs for heavier pellets.
- Before installing the spring, (a) grab the two pins with pliers and pull them apart until it deforms
and becomes like a a compression spring. (b) bend the bottom pin just little bit from vertical, in
the direction of rotation. The above two will keep the spring in place, no matter what.
(that was the second badly designed aspect of the magazine...)
- If your magazine had burrs from previous failures, remove them and make it smooth again.
(it will not happen again anyway..)
- Only use pellets that drop freely in the magazine when loading them. In the case that a pellet
does not fall to the bottom of the magazine, do not force it in. Leave it where it is.
- When screwing back the transparent lid, screw until snug and then backup a bit so that the
lid can rotate freely.

I have the .25 cal version. After the above modifications all pellets worked fine but my
favorites are the copper plated SPITZKUGELN. They are hitting hard, they never get
deformed, they are very accurate and you will not breath any lead dust from the
blowback action.

Hope this helps.
Happy shooting!
1 thing, I sold on ebay for a bit and no longer sell valve pins(i have no horse in this race now) but there are others selling nicely made valves that haven't actually figured out the failure mode and just adding weight to the valve pin itself which changes things a lot(it's not bending and then breaking) . Mag spring tension is the biggest improvement to burping pellets into the action, lubrication went a long ways for me as well. The other one that changed my gun oddly for the better was bottle converting it and adding a moderator which helped that muzzle blast air cycle the action fully. And tuning where the piston is on the operating rod in relation to the muzzle device under the shroud. Short stroking is also a nuisance issue with the old hp design. All things mentioned took it from a 700 piece of trash that put pellets in the fcg every 3rd shot to a never jam 900fps very accurate gun. It just took far too much ingenuity to make it run right out of the box for the price. I think 350 wouldve been a more appropriate retail price for the now discontinued model.

I post this for somebody researching before a used gun purchase. If you can problem solve and tinker this gun won't be a huge problem for you.
 
  • Like
Reactions: darylm and Perle
1 thing, I sold on ebay for a bit and no longer sell valve pins(i have no horse in this race now) but there are others selling nicely made valves that haven't actually figured out the failure mode and just adding weight to the valve pin itself which changes things a lot(it's not bending and then breaking) . Mag spring tension is the biggest improvement to burping pellets into the action, lubrication went a long ways for me as well. The other one that changed my gun oddly for the better was bottle converting it and adding a moderator which helped that muzzle blast air cycle the action fully. And tuning where the piston is on the operating rod in relation to the muzzle device under the shroud. Short stroking is also a nuisance issue with the old hp design. All things mentioned took it from a 700 piece of trash that put pellets in the fcg every 3rd shot to a never jam 900fps very accurate gun. It just took far too much ingenuity to make it run right out of the box for the price. I think 350 wouldve been a more appropriate retail price for the now discontinued model.

I post this for somebody researching before a used gun purchase. If you can problem solve and tinker this gun won't be a huge problem for you.
I don't want to smear the poor guy, but i found the valve pricing exceeded what even i was charging and he's now moved to tool steel shafts and acetal mix plastic like I was using (Good on him) but has Increased the poppet size which now changes airflow to the port for the worse. If the Asian guy that makes those is in here and wants to dm me, I will fill you in on what I learned, know, and how I did them . Making parts for sub 2000 dollar guns is not in my future, and he does really nice machining.
 
I don't want to smear the poor guy, but i found the valve pricing exceeded what even i was charging and he's now moved to tool steel shafts and acetal mix plastic like I was using (Good on him) but has Increased the poppet size which now changes airflow to the port for the worse. If the Asian guy that makes those is in here and wants to dm me, I will fill you in on what I learned, know, and how I did them . Making parts for sub 2000 dollar guns is not in my future, and he does really nice machining.
I use PEEK. Draw back is they sometimes have to be cocked to take air when the tank is empty. I suspect they are using delrin a co-polymer plastic that is cheap but not that durable. I just purchased a rod of Delrin, a homo-polymer rod that is very durable and may seal better. 6Gun, I thought the same thing about the air volume and poppet size. I did some experimenting with some very thin poppets and with some thicker ones.(Larger than stock). I saw NO difference in velocities which I would think would be a measurement. I use HSS rod for the shafts.
 
  • Like
Reactions: 6gun
I use PEEK. Draw back is they sometimes have to be cocked to take air when the tank is empty. I suspect they are using delrin a co-polymer plastic that is cheap but not that durable. I just purchased a rod of Delrin, a homo-polymer rod that is very durable and may seal better. 6Gun, I thought the same thing about the air volume and poppet size. I did some experimenting with some very thin poppets and with some thicker ones.(Larger than stock). I saw NO difference in velocities which I would think would be a measurement. I use HSS rod for the shafts.
I was using an acetal blend at the end with a really unique color because I had a customer read me the riot act about my valve breaking immediately (he took home his buddies identical gun and broke it, then blamed me😂) when i used black high grade delrin. I toyed with some profile changes and saw small increases in flow so i just went with them after I handed out 5 for free to be abused by my buddies, and they didn't fail and haven't to this day.

The gun is discontinued and the money in valve pins isnt worth dealing with most airgun people so I will let the cat out of the bag. The failure mode was aea's reliance on a press or interference fit of metal to a high lubricity plastic combined with the material quality they chose for their poppet, they made a slide hammer essentially. If you have one of mine, it will be near impossible to find out how I did it, but it is in fact possible. The shaft usually twists off before you get it out because mine were assembled with a machine.

Due to the near doubling of labor for that method and my experience with that customer, i pulled the plug (for now) but im still happy to help chill dudes that don't need an annotated print and coc on materials and type acceptance. Other custom part makers and smith's have relayed that they left for the same reasons. Which is why i prefer to stay in the fx budget sphere now or just make stuff for my pals.

Good on you for persistence and hanging with it, you're more patient than I. That said.... If anybody has a line on a 25 cal hpss barrel/probe/magazine me up!
 
  • Like
Reactions: Sicumj
For the shaft I press/spin fit the shaft inside the poppet with a touch of industrial super glue. It is a tight fit shaft and hole same diameter. I have poppets out to friends too without any issues. We used all kinds of plastics in industry and many like delrin (acetyl) ,nylon, fiberglass and garolite were either too soft, broke easily or were too hard to work with (garolite). Now that I'm thinking about it garolite might be an alternative. They do make gears out of the material. It is hell on saw blades. Probably would not seal well. Luckily I just tinker for my own pleasure and help a few people out if asked.

I find the AEA HP series rifles pretty easy to work on. They are a typical blow back action similar to rimfires, with the addition of the piston action seen in many semi-auto shotguns. Regulating the blowback force in the hp's is the key to consistency. Many get around this by filling to a sweet spot of around 3100psi. I didn't go that route I wanted the gun to shoot at 3600 and to shoot strong right off the bat. Smoothing the internals up and going to a harder valve allowed that to happen, The OEM poppet would stick if set for a while or under full pressure. PEEK does not do that.

Was your unique color green? I have installed a few valves for friends and the green poppet showed up once in a while. Another I have seen is a translucent orange/yellow. Both valves seemed durable and I have not had to replace any like that.

One thing about Delrin. Capitol D Delrin is DuPont patented plastic. It is a homoplymer plastic that is very shock and impact resistant and of course expensive. Small case d delrin is a copolymer design and many times confused with DuPont's Delrin. If you see a Delrin capitalized it should be homopolymer if not it is copolymer. Both are acytal.

The magazines are a low hanging fruit for AEA if they wanted to fix their guns. I use Swede mags for my 22 and 25 and what a difference. The original mags can fail on the first day. The steel is not up to standards IMO to be used as a spring. You can wind your own or cut half a coil off and rebend the arm to get more torque. Frankly I don't waste my time with them any more. I would advise not to keep them loaded, I think they will hold up longer.

Poppet durability as you say is a WAG. I seriously do not know how to test for failure unless you made a jig to hold the poppet along with a soleniod to operate it thousands of times. Of course the real test should be under pressure which really complicates the process trying to supply that psi. In this case all you can do is compare the strength of what broke to what you are replacing it with and give it a try. If it breaks you beg for forgiveness and make something stronger. Plastics degrade over time. They are a perishable item.

I too am looking for a SS+ part. I would like to find a 30 cal barrel. I'm considering any 30 barrel with 1/16 twist if the OD is large enough to fit the receiver on the +. The probe should be easy to make, I hope. If you have a 30 cal barrel we may be able to do some trading. My 25 cal barrel though would be 10 inches instead of 8. I have mags IN 25 brand new.
 
Last edited:
  • Like
Reactions: 6gun
For the shaft I press/spin fit the shaft inside the poppet with a touch of industrial super glue. It is a tight fit shaft and hole same diameter. I have poppets out to friends too without any issues. We used all kinds of plastics in industry and many like delrin (acetyl) ,nylon, fiberglass and garolite were either too soft, broke easily or were too hard to work with (garolite). Now that I'm thinking about it garolite might be an alternative. They do make gears out of the material. It is hell on saw blades. Probably would not seal well. Luckily I just tinker for my own pleasure and help a few people out if asked.

I find the AEA HP series rifles pretty easy to work on. They are a typical blow back action similar to rimfires, with the addition of the piston action seen in many semi-auto shotguns. Regulating the blowback force in the hp's is the key to consistency. Many get around this by filling to a sweet spot of around 3100psi. I didn't go that route I wanted the gun to shoot at 3600 and to shoot strong right off the bat. Smoothing the internals up and going to a harder valve allowed that to happen, The OEM poppet would stick if set for a while or under full pressure. PEEK does not do that.

Was your unique color green? I have installed a few valves for friends and the green poppet showed up once in a while. Another I have seen is a translucent orange/yellow. Both valves seemed durable and I have not had to replace any like that.

One thing about Delrin. Capitol D Delrin is DuPont patented plastic. It is a homoplymer plastic that is very shock and impact resistant and of course expensive. Small case d delrin is a copolymer design and many times confused with DuPont's Delrin. If you see a Delrin capitalized it should be homopolymer if not it is copolymer. Both are acytal.

The magazines are a low hanging fruit for AEA if they wanted to fix their guns. I use Swede mags for my 22 and 25 and what a difference. The original mags can fail on the first day. The steel is not up to standards IMO to be used as a spring. You can wind your own or cut half a coil off and rebend the arm to get more torque. Frankly I don't waste my time with them any more. I would advise not to keep them loaded, I think they will hold up longer.

Poppet durability as you say is a WAG. I seriously do not know how to test for failure unless you made a jig to hold the poppet along with a soleniod to operate it thousands of times. Of course the real test should be under pressure which really complicates the process trying to supply that psi. In this case all you can do is compare the strength of what broke to what you are replacing it with and give it a try. If it breaks you beg for forgiveness and make something stronger. Plastics degrade over time. They are a perishable item.

I too am looking for a SS+ part. I would like to find a 30 cal barrel. I'm considering any 30 barrel with 1/16 twist if the OD is large enough to fit the receiver on the +. The probe should be easy to make, I hope. If you have a 30 cal barrel we may be able to do some trading. My 25 cal barrel though would be 10 inches instead of 8. I have mags IN 25 brand new.
I was green at the end! You are correct on acetyl being generic delrin. There was another material or two I had considered. Turqite was too spendy and had to get and another from my wife's work was 1k per foot at straight material cost! I don't have a 30 barrel but I did see one recently. I have a 22 on mine and the gun had to shoot in a yellow range fill.

The hp is ez to work on, simple and few orings. Tuning the piston position on the op rod was most fruitful for me in cycling as well(zero space to the muzzle ring) . That's where I hate it. It's 350 dollar full retail gun, not 700 imo. Basically change the valve and reassemble the gun to your specs since china just slammed it together willy nilly.

Funny you mention the other target practice. I started with 20% forgings 21 years ago and competitive rimfire while shooting a benjamin 392 and then an mrod. Shortly after.