1 piece hop-up install

[HKGhost]

Hello ASC members. I'm looking to install a 1 piece hop-up chamber in my JG M4A1. Now the problem is my M4 comes with a 2 piece hop-up unit so I'm planing on modifying the lower receiver to accept the 1 piece. I need to know exactly how the lower receiver with a 1 piece hop-up looks. So if anyone has any good clear pics of the lower receiver (top and front view) it would help me a lot. Another question is, do I need to change/mod the air nozzle so bbs would feed properly after installing the 1 piece hop-up? (had feeding problems before) Thank you.

[Kos-Mos]

You need to remove everything in the magwell (lower section of the hop-up), and cut the front part of the lower receiver between the two prongs of the front body pin.

Cut at least to the middle of the prong, then work along to make it clear the new hop-up unit.

I just installed one in mine. I will see if I can find a picture tonight.

[HKGhost]

Thanks for the information. If you can take some pic, that would great. I kinda get the idea. Saw some pics online but I wasn't sure about the front part between the prong for locking pin. Do you know if I need to change/mod the air nozzle for it to feed properly? Thanks

Originally Posted by Kos-Mos

You need to remove everything in the magwell (lower section of the hop-up), and cut the front part of the lower receiver between the two prongs of the front body pin.

Cut at least to the middle of the prong, then work along to make it clear the new hop-up unit.

I just installed one in mine. I will see if I can find a picture tonight.

[HKGhost]

I've found a step by step instruction on how to mod the lower receiver to accept a 1 piece hop up chamber. For anyone else that wants to do this mod, here is the link: Prometheus Metal Hop-Up Chamber Assembly for M4 - Filipino Airsoft (FAS) - Forum.

[HKGhost]

I have successfully modified my receiver to accept the one piece hop up. Took 5+ hours to do all the work which also include assemble/disassemble the gun about 4-5 times. It could have taken a shorter amount of time if I knew exactly what was needed to be modded. Gun shoots great just like before. For anyone that wants to do this, DON'T!, unless you like to tinker and are willing to put in the time and effort. One more things is, you will lose the quick field strip feature unless you chop off the rear tabs and add lips like the CA upper receiver. I will post some pics if anyone wants to see the mod. Thanks.