Need help with hop up
 

I bought a KA receiver and it came with a metal one piece hop up. I purchased a 6.03 Prometheus tightbore as well. Now part of the hop up is the little brass washer that goes over the inner barrel and sits just inside the hop up, well the inner barrel is too large for this ring. Is this a big concern? Do I need to find a larger one or can I just omit this small part?

I lost the ring for one of my AEGs, didnt make a damn difference

Yep and your one to trust.

It's good to have tom but it'll work without it. It just supports it really and makes the barrel and hop-up assembly a solid piece that's not just connected by rubber. So It's obviously good for consistency and what not but in alot of setups in can go un-noticed.

If the C clip isn't good enough, you can wrap it with teflon tape which eliminates the gap/wobble (if any) and air leak.

THIS /\

I forgot about that. I've done that a few times to solve air seal issues, Teflon tape is great stuff to have for this situation.

it does at least two things...
1. helps to center the hopup unit and barrel and hold them in line
2. helps the barrel/rubber from moving forward...which will create air leaks and maybe feeding issues

you can ream out the ring or use some fine grit emery paper to open it up. take your time with it.

teflon taping the barrel/rubber will help "jam" the barrel into the hopup so it doesn't move forward...careful not to contort the rubber if it's too tight.

best of luck