Radiograph of an incorrectly-assembled rifle

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Odd Job

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I have a Rimfire Magic .22LR in the 10-22 family, with a receiver machined here in the UK. It is a nice rifle with a Volquartsen barrel, Yankee Hill Machine riser and a Burris Fast Fire III reflex dot. The trigger unit is an enhanced Ruger BX and the bolt is made by Ruger also. Some other pieces are third party but they are not important here.

I stripped the rifle and took various photographs and radiographs of it, because that's one of my hobbies. Here's the rifle being X-rayed at the point where I had reassembled it after X-raying the innards:

upload_2019-11-8_18-47-38.png

And here is the radiograph:

upload_2019-11-8_18-50-52.png

Let's see how good the THR members are, in analysing that radiograph...

1) You get a virtual bronze medal if you can point out the evidence that proves I reassembled the rifle incorrectly.
2) You get a virtual silver medal if you can tell me what the symptoms of this incorrect reassembly are.
3) You get a virtual gold medal if you can tell me why the left hand side of that image has a lighter grey vignette effect, compared to the right. It has nothing to do with the gun, it would happen even if there was nothing on the X-ray cassette. You may have to phone a friend in the radiology department to get this one, it is not easy!
 
I have a Rimfire Magic .22LR in the 10-22 family, with a receiver machined here in the UK. It is a nice rifle with a Volquartsen barrel, Yankee Hill Machine riser and a Burris Fast Fire III reflex dot. The trigger unit is an enhanced Ruger BX and the bolt is made by Ruger also. Some other pieces are third party but they are not important here.

I stripped the rifle and took various photographs and radiographs of it, because that's one of my hobbies. Here's the rifle being X-rayed at the point where I had reassembled it after X-raying the innards:

View attachment 870387

And here is the radiograph:

View attachment 870388

Let's see how good the THR members are, in analysing that radiograph...

1) You get a virtual bronze medal if you can point out the evidence that proves I reassembled the rifle incorrectly.
2) You get a virtual silver medal if you can tell me what the symptoms of this incorrect reassembly are.
3) You get a virtual gold medal if you can tell me why the left hand side of that image has a lighter grey vignette effect, compared to the right. It has nothing to do with the gun, it would happen even if there was nothing on the X-ray cassette. You may have to phone a friend in the radiology department to get this one, it is not easy!

I tried flipping my monitor upside down to read the answers but I couldn't find em...
 
Here it is, side by side. On the left, incorrectly assembled with the ejector rotated to the rear. On the right, correctly assembled with the ejector facing to the front:

upload_2019-11-8_23-8-5.png
 
Part of me wants to say that it is some sort of environmental effect like sunlight but that sounds awful suspect.

It almost looks like that end is a little bit blurrier and out of focus compared to the rest of the image. Which raises questions. Perhaps the film is slightly curved or some sort of interference with the projector?
Trying real hard not to cheat and resort to googling.
 
Thanks for that rabbit hole.
Then I had to grab a led light and a chronograph diffuser to emulate the source and replicate the pattern.
 
3) You get a virtual gold medal if you can tell me why the left hand side of that image has a lighter grey vignette effect, compared to the right. It has nothing to do with the gun, it would happen even if there was nothing on the X-ray cassette. You may have to phone a friend in the radiology department to get this one, it is not easy!
Is it due to the way the shutter moves?
 
I had figure out what the problem part was, but I hadn’t figured out what it’s function was. The fading on the edge I’m guessing to be some sort of “noise” from the machine.
 
Nobody will get it, most radiographers today won't get it either!
It's called the anode heel effect, where the anode itself attenuates the X-ray beam at one end of the beam more than the other. It comes into effect at the periphery of an exposure, if you are X-raying long subjects.
Here's one more example, this time an A-TEC A12 shotgun suppressor X-rayed on a digital detector.

upload_2019-11-9_10-59-11.png

In the first exposure I had the X-ray tube aligned so that the anode was over the left hand side of the suppressor. That side of the radiograph shows the anode heel effect:

upload_2019-11-9_11-3-5.png

Merely by rotating the X-ray tube 90 degrees on its Z-axis, the artefact is eliminated:

upload_2019-11-9_11-4-2.png

The bottom line is: if you want your long gun or suppressor parts X-rayed, ask the radiographer to make sure that the tube axis is 90 degrees rotated relative to the long axis of the part being X-rayed. Like this:

upload_2019-11-9_11-13-12.png

In the image above, the X-ray tube is in the cylinder up top (the cathode side towards me as I took the photo). Another way to remember it is to have the handle on the tube (the orange hoop at the top left of the unit) rotated 90 degrees to the subject (in this case the suppressor).
 
Why does it look like the trigger group pins are in at an angle? The safety looks elongated also.
bassjam got it before I opened this thread, but I did spot the flipped ejector immediately. I've 'fixed' many of them. Two minutes, a screwdriver and a punch to get to it.
 
Why does it look like the trigger group pins are in at an angle?

That's because the X-ray beam is composed of diverging rays. So if you wanted to X-ray a pin without any kind of oblique projection, you would have to aim the beam at the pin directly. There are a bunch of other technical points to add, but that's the simple answer: the X-ray beam was centred forward of the receiver.
It is the same reason why the choke thread suppressor adapter on the A12 looks like it has an elliptical opening on the radiograph. If the machine was brought over to that specific area, the ellipse would disappear and it would appear as a straight line. But then the other end of the suppressor would look markedly elongated.
 
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