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.
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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!
) 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. 