AR15 Brass dings and Headstamp slices

ephul

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Need some help. I've got a White Oak Armament SPR 18" upper with rifle length gas. I've been running some reloads through it to find the right combination.

I noticed a few slight things. The rifle cycles great. No issues. However, I'm getting a consistent ding in the same spot of all my brass. I think its hitting on the deflector just outside the receiver.. not on the furthest point of the deflector.

Secondly, it appears as though the extractor is slicing my headstamp ever so slightly. What could fix this?

There doesn't appear to be any signs of high pressure. I've been loading low to mid range as far as powder, and have been seating the bullet less deep. Been doing 2.26".

What would fix these two issues? Photos attached.
 

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I believe the path of the ejected brass is determined by the gas pressure.
Ideally you want the brass to eject slightly forward of straight out, if straight out were 3:00, 2-2:30 is what you're looking for.
The fact that your running a little lite on the pressure and hitting the deflector, 4 or 5:00 would make sense.
A hotter load should help.
The extractor might need to be deburred and polished, hope this helps.
 
According to the ajustable gas blocks I've installed. They says 3-4pm is perfect.
Some guys run a small piece is tape to help with dent. But gas is also a issue with it cutting The brass.
 
I'm also getting slight marks on the case mouth as well.

Nothing major at all. After tumbling with SS pins, a lot of it would hardly be noticeable. But curious if all three of these marks together are from one issue.
 
The downside of auto-loaders seems to be commonly brass dings, etc. I had a browning bar that loved to chew on brass. The AR15 was not much better. Tried using a brass catcher, but it was a PITA. Now I just adjust the gas block, recover as much as possible on the AR and not fret it so much. Sold the BAR and replaced it with bolt action.
Good luck!
 
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