QB78D first impressions.

[pharoah007]

Well I got her all apprat and back together this afternoon :)

Used emery cloth, steel wool (#1 and #0000) along with dowels and a drill to smooth out all the ruff edges.

The barrel set screw hold had a big burr in it, thus destroying the stock O-rings.





Factory transfer port seal wad fubar, as expected.




Installed all new O-rings and she is back on the firing line :)

I do notice when I fire her, I feel some gas escaping form the transfer port area :(

I do not know how to fix this as I have installed the new seal as best I can. I say as best I can because the holes drilled in the breach from the factory do not line up well with the bottom of the breach :(




I can not think of a better way to seal up this transfer port area as the hole is off center....any thoughts everyone???

[AirGunEric]

Remove a bit of the polyurethane seal so it is a slight bit sloped toward the center, then the breech clamping down on it should allow it to seal. Sadly, that slightly offset hole issue is one of the more common issues with these rifles.

[rsterne]

WOW!.... I've never seen holes so badly aligned on any airgun.... The only good thing is that the bolt holes and the barrel port in the breech all line up (although off center), so (assuming the bolt holes in the tube are correct) at least the transfer port should line up.... Perhaps filing a flat across the transfer port location (the proper way would be to mill it) and then using a poly port might work?....

Industry Brand needs to have a hard look at their QC system....

Bob

[pharoah007]

WOW!.... I've never seen holes so badly aligned on any airgun.... The only good thing is that the bolt holes and the barrel port in the breech all line up (although off center), so (assuming the bolt holes in the tube are correct) at least the transfer port should line up.... Perhaps filing a flat across the transfer port location (the proper way would be to mill it) and then using a poly port might work?....

Industry Brand needs to have a hard look at their QC system....

Bob

yeah, that is one thing I was not expecting.....but what can I do :(

I am picking my brain...removable weather stripping may came into play....the stuff that comes in a caulking tube then dries to a gasket like material.

[rsterne]

I think I would be tempted to purchase another breech.... but that's just me....

Bob

[pharoah007]

I think I would be tempted to purchase another breech.... but that's just me....

Bob

I agree...but I am morally opposed to purchasing something to replace something that was defective out of the box.

This is NOT a attack against where I purchased the QB78D as I understand the process of Chinese quality control ;)

[SeanMP]

Wow!

I'll echo Bob's sentiments....certainly the worst I've ever seen.

I have no suggestions for an easy fix on the breech.

I would however gently file the bottom side hole (securing screw) so that the transfer port can rotate to center. I have had to do this regularly.

[pharoah007]

I wonder if the manufacturer would replace this breach?

[remtom1200]

A curveball barrel is one thing, but I have to say that this machining is something that should be sent back instead of trying to fix. I am curious how the rear screw would fit through the trigger assembly, tube, cap, breech and cap? I ran into a situation with my riser block having to be aligned very well or canting the breech would bind the hammer cocking pin and block pin against the slots in the breech making operating the bolt impossible.

[pharoah007]

[QUOTE=remtom1200;6682 I am curious how the rear screw would fit through the trigger assembly, tube, cap, breech and cap?[/QUOTE]

It barely does.

If you tighten the breach screw all the way...you will NEVER get the rear trigger---->tube---> cap screw in there.

You have to keep whatever screw you put in first loose, then line it all up with a bit of pressure...get second screw to start to thread....then tighten them both.