•• WTF happened to my upper? ••

SudburyShooter

SudburyShooter

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•• WTF happened to my upper? ••

The upper is relatively new, has 400 rounds out of it at best.
No ftf, fte, been a smooth ride. After the last range session I noticed the ejection cover was stiff.
The spring wouldn't push it open all the way. After taking the rifle apart I noticed this bend in the
mag well portion.

2wnahwz.jpg

dwexoh.jpg


Has this happened to anyone before? I almost think it must of been there from the beginning.
But the cover was functioning fine.
 
I'd be interested in unbiased theories first before brand loyalty, or the opposite, influence a diagnosis.
 
Did you experience a double feed or an over bolt jam? Drop it? Did someone inadvertently knock it of the rack?
 
So its an NEA ? :p

All joking aside, thats bad ! I have seen something similar and will try to ask my friend about it. I think his problem came from a bullet pushed in the casing that caused over pressure and it went by the weakest point.

It appeared last time you shot and before it was all straight ?
 
How did you take apart the upper? Or conversely, how did you assemble the upper in the first place?

Specifically, how did you hold the upper when you removed/installed the barrel nut?

The damage looks similar to what you'd see if you clamped the upper in a vice (as opposed to holding the barrel in a vice, or using a BEV block or a Reaction Rod) to undo/tighten the barrel nut.

P.s. if that's a spikes, then I'm never buying one, the mill marks look like a bag of $hit
 
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http://www.canadiangunnutz.com/foru...15-family-portraits-)?p=12101023#post12101023 post 89

Bottom of the ejector port looks wonky in this pic.....

It does look like a point of impact on the bottom.
Click to expand...

It looks like damage caused to the anodizing by clamping. Virtually impossible for anything to impact against that area with the upper closed on the lower.....
There is another scuff mark on the other side of the upper too.

I would inspect your vice block.....

Which vice block did you use? Got a pic? Does it have the support rod that goes through the centre of the upper?
 
*MALICE* said:
http://www.canadiangunnutz.com/foru...15-family-portraits-)?p=12101023#post12101023 post 89

Bottom of the ejector port looks wonky in this pic.....



It looks like damage caused to the anodizing by clamping. Virtually impossible for anything to impact against that area with the upper closed on the lower.....
There is another scuff mark on the other side of the upper too.

I would inspect your vice block.....

Which vice block did you use? Got a pic?
Click to expand...

One without a insert
 
Anywho.....

Only thing you can do now is gently push/coerce it back into shape.

I would advise buying a better method of installing barrel nuts. Those clamshell types arent the greatest.....

I would also advise using vice jaws for clamping on the barrel. The barrel is stronger than the upper.

barrelviseblockmethod.jpg

As per the Technical Manual

Or you could buy a Bev Block or reaction rod. Personally though, I'm not 100% in love with the idea of them for loosening barrel nuts. While hypothetically the barrel extension should not be able to unthread (tightened to 150 ft/lbs) ive seen a few barrels where they werent on that tight.....
 
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I'll look into a barrel vise, pretty bummed as I know the torque wrench never exceeded 75ft/lbs.
I might tinker with trying to bend it back but if I make it worse it might put me out worse.
 
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