KSC USP Hop-Up Problems
 

I just bought a KSC USP .45 from someone here on ASC advertised as working perfectly and with 2 good mags and 1 leaking mag. I recieved the gun to find 3 leaking mags and one of them was broken (Rattling inside). The mags I can fix or replace. The safety was also not working but I hear this is a common problem -just frustrating since it was advertised as working.

The real problem I have is that I discovered that the hop-up rubber is shredded. I knocked out the pin that was holding the inner barrel into the outer barrel and got it to slide out about 1cm but it won't come any further. This is enough to see that the ball bearing is misaligned and the rubber has a big hole in it underneath the ball bearing and the area is deformed and torn. I'm guessing one of the previous owners torqued the hop-up wrench waaay too hard.

Now, I can't figure out how to get the inner barrel out any further so I can take out the old rubber bucking or examine it for further problems. The diagrams in the manual that came with the gun are for the plastic outer barrel USP compact version. This is the metal outer barrel and slide .45 version and the pictures don't match up. Anybody have any experiences with this?

Finally - where can I get a new rubber? Airsoftparts.ca lists it but for $18 and out of stock.

you can contact Tirador on the forums for any KSC original parts

http://img44.imageshack.us/img44/5741/barrel.jpg
I'm at this stage now. I can't get the hop-up rubber out of the retention ring. The manual says to slide forward but that metal ring doesn't want to move nomatter how much force I put on it or what direction I rotate it. You can see the hole in the hop-up rubber.

Thanks Daiviet, I'll talk to Tirador. I think I might be able to get parts from KWAUSA as well.

You should be able to pull the barrel off the hopup assembly then slide the rubber out.

I can't get it to come off. I have tried pushing it forward and pulling it back and rotating.

Use more force. you will likely destroy the hop up rubber. Be ready to buy a new one though. I recommend get from Traidor, I bought like 5 of them while I still had KSC gun.

KND

I haven't been able to contact tirador for like 2 weeks now. Maybe he is too busy with his AEG stuff.

Same, no replies in a month almost, you can get your rubbers at Den Trinity.

I'm going to try contacting Trinador through his website. He doesn't check ASC much.

How much did those rubbers cost from Trinador? If I can't get in touch with him, they are $5 each from KWAUSA. I will try applying more force to the hop-up unit (push forward so it slides down the barrel right?)

Thanks for the advice, I got the hop-up unit separated. The bucking was so torn up, it was wedged between the barrel and the hop up ring really hard. I had to apply a lot of force.

I've got a question about the ring now. Is it common to overtorque these? Could it cause damage? I am looking at the hop-up adjustment ring and there is 1 metal tab on it and 2 parts that look like they could have been metal tabs (or maybe they are just raised areas with wear). Are there supposed to be 3 tabs? Or just 1?

See picture:
http://img26.imageshack.us/img26/8351/hopupunit.jpg

First question is, why didn't you contact the seller and complain?

Who says I didn't? That's done and past and dealt with (partial refund to cover the cost of a new hop-up rubber and misc). I'm trying to fix this now and this thread is asking for info from people who have worked on USPs before because I obviously haven't :)

I'm placing an order for parts for this gun soon either through their US affiliate at KWAUsa or Trinador and I would like to know if my hop-up adjustment ring is normal incase I need a new one.