Other causes for flight path curving?

[slipstream]

Alright, good news first: I disassembled my KWA Mac 11 and managed to get it to cycle flawlessly without getting bb's backed up in the barrel or double feeding.

Bad news: all the shots are consistently curving to the right.

Now, keep in mind before this disassembly it shot perfectly straight. I did not mess with the hop up at all, the bucking is aligned properly (unless it magically changed somehow), same as before. The barrel is squeaky clean. This leads me to believe that this may have something to do with the way the bolt is situated/just slightly out of alignment.

Any input or experience with similar issues appreciated.

[Geschutz]

To name a few that I have seen.

Worn or damaged hop up rubber. The inner barrel is not sitting straight into the hop up.

Warped inner barrel. Unclean inner barrel, shredded inside of inner barrel

[Merchant]

Just real quick shine a light down the back of the barrel and look down the end where the bb exits with the hop up turned on. Make sure the hop up unit is alligned at a perfect 90 degree angle. I've noticed that the slightest twisting of the inner barrel will change the hop up position on my KWA USPc.

[Bad Karma]

Peyronie's disease.

[ogrejager]

Peyronie's disease.

Good one. I had to google it.

The real question is--how do you know about it? Too much craigslist time?

[Bad Karma]

My tool looks like a bleeding banana.

No, seriously, I just saw the "curved flight path" thing and the first thing that popped into my head was phallic (which I guess really isn't that surprising coming from me). I knew there was a disease for curvature of the cock, but I, too, had to first google it to get the name.

[Snake Doc]

My tool looks like a f***ing banana.

No, seriously, I just saw the "curved flight path" thing and the first thing that popped into my head was phallic (which I guess really isn't that surprising coming from me). I knew there was a disease for curvature of the cock, but I, too, had to first google it to get the name.

I had that epiphany too

[slipstream]

Just real quick shine a light down the back of the barrel and look down the end where the bb exits with the hop up turned on. Make sure the hop up unit is alligned at a perfect 90 degree angle. I've noticed that the slightest twisting of the inner barrel will change the hop up position on my KWA USPc.

I'll make sure to check that.

Karma: I thought you would post something like that

[slipstream]

Ok, so I took a look down the barrel after completely disassembling the gun (again lol).

Now I am noticing that the part of the bucking that protrudes down into the barrel is pretty much right where is should be, twisted maybe 5 degrees or so CCW, very little if any at all. But I also noticed that what looks like little "nubs" on the back of the bucking were not perfectly level (while looking down the barrel from the chamber side, shooters perspective). But wouldn't this cause the bb to go to the left instead?

sorta like this:

The amount of twisting depicted in my awesome paint image is slightly exaggerated.

[DMitri]

Hold your replica sideways and fire it, see what happens?

Yes, the nub needs to be perpendicular to the ground.

[slipstream]

Yes, the nub needs to be perpendicular to the ground.

Yes, I'm aware of the most elementary rule of proper hop-up set up. But what I am observing in the barrel is contrary to the results I am getting.