Post by: Rob on July 13, 2021, 07:26:36 PM
The rear of the upper has a knurled nut /screw with an oring seal on it. It threads into the upper reciever where the charging handle would normally protrude.
One edge of the nut is flat ao that it will sit against the lower and won't spin out
Here is my question. The nut is loose with a gap betwee. The oring and the upper, however if I thread it one more revolution in, it is super tight and the oring extrudeds. What is the purpose of this nut/screw? My assumption is that it is there to block gasses from blasting your face while firing. Any possible solutions? Was thinking of finding a thinner oring, or adding a washer. Or removing it!
Will add a photo shortly
Post by: Rob on July 13, 2021, 07:38:34 PM
Post by: jay.sharkbait on July 13, 2021, 08:05:42 PM
Post by: Caseknife on July 13, 2021, 08:13:51 PM
Post by: bustedoldman on July 13, 2021, 08:15:28 PM
Photo. The white washer is in place to close the gap (I added it to demonstrate the issue). If i remive the washer and go one full revolution the oring extrudes. Less and the nut/screw wont be in a position to allow the upper to snug against the lower and close.
https://bearcreekarsenal.tawk.help/article/what-is-this-plug-on-the-back-of-my-side-charging-upper
Does this help?
Post by: Dan-o on July 13, 2021, 08:15:51 PM
Just picked up 2 side chargers for a son and I to build twin ARs.
Ours also have that thing on the back that spins a little loose.
Just got the final parts today, so haven't out them together yet.
What is that mystery nut for? ? ?
Got ours from Bear creak arsenal.
Post by: Dan-o on July 13, 2021, 08:17:12 PM
That was fast!!
Thanks
Post by: Dan-o on July 13, 2021, 08:19:29 PM
Per the referenced link, don't shim/tighten it.
Its designed to operate loose.
Post by: Rob on July 14, 2021, 04:21:16 AM