Removing the Inner Barrel [SiG 552]

[Rotting]

Yes I know, more run of the mill questions.

Today I disassembled my SiG 552 for the first time because I wanted to learn how it all got put together, as well, the first thing I'll be upgrading is the inner barrel to a 6.03mm or a 6.04mm. Problem is that inner barrel is attached to what I'm quite sure is the hop-up. I can't disconnect it by any means I've been doing, which is mainly just pulling as hard as I can on the bugger. Is it normal to be this difficult to get off, or am I just doing it wrong?

I don't really want to put this back together until I've at least learned one thing about it's insides.



Thanks in advance!

[Disco_Dante]

I'd love to help you, but my Sig is in a different city right now. I can't quite remember how to take the hop up unit off, but I remember it was pretty simple. The sig uses a g3 hopup unit, so try googling G3 hop up removal or something like that.

[CDN_Stalker]

There's likely a plastic C-clip that holds the hop up and barrel together, or a pair of screws holding it together. I installed one once like two years ago, and can't remember that exactly the 552 has for a connection, but if you yank it too hard or try to force it, you'll break the hop up and good luck finding a replacement for it.............. at least one that isn't still attached to another 552.

And want to know what happens when you screw up the part that holds the hop up unti and barrel together? You will either get double feeding and very low fps from the airleak between the rubber and the nozzle, or worst case, your inner barrel will literally fly out the front end and onto the floor (happened to an Armalite I was workign on one day, the owner had forgotten to put the clip back in).

[Rotting]

All I can seem to find is a pin that was behind the hop-up part. I removed the pin thinking it might allow some sort of slack, but still no luck in a disassembly. Doesn't seem to have any screws attached to it. It's actually beginning to really bug me now, heh.

[CDN_Stalker]

That's likely the hinge pin that the hop up lever pivots on. I'll see what I can find with a manual search.

EDIT: Yup, there is plastic C-clip that is on the underside of the hop up unit, use a small slotted screwdriver to pop it out from the side, but be careful, those things break and will cause the above problems, and you'd have to buy a new hop up unit just to replace the clip.

http://www.depot53support.com/pdf/SIG552%20TM.pdf

[Rotting]

Originally Posted by CDN_Stalker

That's likely the hinge pin that the hop up lever pivots on. I'll see what I can find with a manual search.

Yea, I put it back in since the hop-up part that you spin was just spinning round and round without stopping.

[Rotting]

Something must really, really not like me.

After looking at that manual and reading it over, I couldn't find anything in relation. I tried looking for a C-clip a little closer, and still couldn't really find anything. Instead of just saying that and leaving everyone who's making their efforts blind, here's a picture of what I'm dealing with. If there's a C-clip there and I'm missing it, something is terribly wrong.



It actually doesn't even look like any of the G36 hop-ups. Those ones I can clearly see where the c-clip is without really having to make the effort to do so. This one seems... well, odd.

[Darklen]

Just pop the ribbed wheel in the front off. It literally pops off. The c-clip is underneath it. Carefully pop the clip off and slowly slide the inner barrel out, you might have to twist it a bit, so be carefull you don't pull too hard or go too fast or you might damage your hopup sleeve.

[Rotting]

Alright. I've gotten it apart and I put it back together, but now it looks like the little brass ring is protruding further than it was before I had taken it apart. Is this brass ring supposed to be over the sleeve? I don't want to put the entire gun back together just to find out that that little brass ring was very important and it's position isn't right because it's sticking out a bit.

Thanks in advance!

EDIT: Nevermind, I figured this one out myself, heh.

[The Saint]

Little brass ring doesn't go over the hopup rubber sleeve. After reassembling the rest of the inner barrel assembly, simply slide the brass ring down the barrel and push it into the space between the inner barrel and the hopup unit. It doesn't have to go deep, just push it until you can't see it from the side anymore.