Modify AEG Cylinder Set for M4/M4 RIS

verified buyer

First of all, the product description is wrong when it says this cylinder set comes with an aluminum piston head...it is actually a black pom polycarb piston head with clean vented holes.

The cylinder head is high quality stainless steel with good quality double ring rubber seal that fits very tight with the cylinder which provides awesome air sealing.

the cylinder is virtually spotless and dust free internally you can use it right away without cleaning , very high quality.

the piston head is guarder quality black polycarb with clean vented holes. It is solid, tough, reliable and comes with ball bearings for the spring so make sure u tighten the screws very tight or else the spring will spin your bearings and polycarb screw support loose (the little polycarb hat the holds the bearings together with the help of the screw).

the included piston is purple/grape colored polycarb with last tooth being metal. It is guarder quality and durable.

BUT, this kit has one FLAW...The O-Ring for the piston head is TOO SMALL for the cylinder and provides terrible compression. It seems like both the bore up and non bore up echo 1 cylinder sets have O Rings that are too small for the cylinder.

As a side note I am using this set in a stock spring ICS M4 shooting at around 310 fps and so far everything is still brand new after going through 20000 bbs today. With such low stress settings and an 8.4v battery, I think this gun will will last me a million or so shots with this durable kit installed. However, higher ROF and fps settings will obviously cut down gun life down dramatically.

i just bought this yesterday after school. dropped by and picked this sucker up along with a prowin piston. i installed it later in the night at like 11. everything was very easy to put in. it was recommended by one of the guys to switch out the oring on the piston head as apparently it doesnt create a proper seal causing loss of pressure. anyways everything is a VERY snug fit. after replacing the oring with the original one the piston takes a large amount of force to manually push into the cylinder. the cylinder head sticks on nicely as well. i didnt use the piston it came with as it is supposedly only able to withstand up to a spring of 1 joule. so installation was a breeze and i reassembled everything. took it outside to shoot and i noticed it sounded alot better than the stock stuff. noticably quieter. only loud thing is the motor... so i shot a couple on semi. and then i went to full auto. i got a higher rof i think its from the lighter piston but im not sure. after shooting about a 40 rounds off. i heard the gb give off a nasty errr. so i immediately stopped shooting. i took it inside and checked it out. it sounded like the piston was stripped or something stripped. so i took everything apart and checked. nothing. then i noticed alot of bbs stuck in my silencer. so the blockage caused the air shot out from the nozzle to be pushed back causing improper cycling of the piston. lets say i was very relieved that i didnt just waste 20 dollars on a piston. to say the least this kit is amazing. great compression. everything looks like high quality parts. give it a give it a 10 outta 10

verified buyer

Product Information:
Th kit is great!! Adds alot of compression to your AEG. The Piston Head is not aluminum but polycarb as well as the piston. Very easy to install. New air nozzle seals tightly to the tappet plate as well as the cylinder head. Cylinder is super smooth and precisionly pollished. P-head s none the less ported. The piston has a clear purple color to it, its no very appealing but then again it does not need to be. The piston head o-ring is fine and provides an excellent seal...seriously people its called cylinder lube. BTW I installed this into my custom m733 which preiously was an m16 performed like a champ. Of coarse before doing anything you should shim and lube your gearbox before. Also picked up a ball bearing spring guide. It also has a Madbull M120 installed running on a large 9.6v 4500 batt. Oh and the nozzle which seems to add accuracy....don't know why but its alot better.


Pros:
cheap
reliable
quality parts
great compression





Cons:
none