nova blowback

PeteCoffey · 05-24-2005, 04:17 PM

And they all have the same problem? I would look for a scratch or crack on the inside of the breech area where the barrel O-rings seal against the breech... as it's drawing the barrel back pressure is somehow getting in to feedtube area. Sorry I did'nt read you earlier post more carefully about it happening on the draw back....
Install the barrel without the shroud & gas up... pull the barrel itself away from the marker... it shouldn't release any pressure to the feed tube area, just spring back when you let go...If it does leak while pulling the barrel I'd look for something wrong on the inside of the breech.

gs123 · 05-27-2005, 09:44 AM

I did that, it has a very, very slight leak. It is not much to make a diffrence. Do you know if that would cause the blowback?
thanks

PeteCoffey · 05-27-2005, 04:26 PM

I would think anything causing the blowback would be pretty noticable...gob the lithium grease on the 3 barrel o-rings & see if that helps... very strange ...

gs123 · 05-28-2005, 10:02 PM

I have put a lot of grease on the o-rings, it does not help.

kayo09 · 05-30-2005, 08:06 AM

It may be your breach itself. There are two o-rings around the breach. I believe they are 222's. They isolate your feed tube from any air. These O-rings are around your breach, between the breach and the main body of your gun. Behind the front part of the breach is an accumlator. If there are any leaks in your orings air can leak from either the back or front oring into your feed tube.

Remove your trigger frame completely. Note how the holes on the front or your gun line up, front portion of the body (flat part). Remove your feed tube. Be gentle with it when you put it back in.

Remove your regulator assembly and all your internals. Get a large dowel rod and push the breach or tap on the dowel rod with a hammer to slowly push the breach assembly out the front of the gun.

My breach came out in three parts, breach back, brass spacer and breach front. Replace the orings on the breach and re assemble. The holes in the back part of the breach need to line up with the holes in the bottom (flat part) of the body.

Take your time and do this when you have plenty of time to work on it. I took mine apart this weekend and it took me about 3 hours to completly disassemble, repair and reassemble.

Hope this helps.

Kayo