AR 10 in 6.5 CM
Criterion bbl from Fulton Armory, JP high pressure bolt, headspaced by Fulton with this bbl.
Rifle is shooting great, gas is still wide open for now as I am breaking it in, I can turn down gas, JP gas block.

I know nothing about brass or reloading, am keeping brass for future 6.5 reloading.
Thought i would let the experts tell me what they see.
I assume the dents are from the deflector, I am putting a soft velcro tab there now to see if that will stop the dents.
The scratches on the neck are not cuts or cracks, just mild scratches, from sharp bbl extension maybe ?
Extractor leave a lil mild burr where it grabs ?
Thanks for looking, eventually I will reload for this rifle.
<img src="https://www.AR15.Com/media/mediaFiles/200513/IMG-3156-108604.jpg  " />
<img src="https://www.AR15.Com/media/mediaFiles/200513/IMG-3168-109252.jpg  " />
<img src="https://www.AR15.Com/media/mediaFiles/200513/IMG-3166-109250.jpg  " />
<img src="https://www.AR15.Com/media/mediaFiles/200513/IMG-3165-109249.jpg  " />
<img src="https://www.AR15.Com/media/mediaFiles/200513/IMG-3164-109248.jpg  " />
<img src="https://www.AR15.Com/media/mediaFiles/200513/IMG-3163-109247.jpg  " />
<img src="https://www.AR15.Com/media/mediaFiles/200513/IMG-3162-109246.jpg  " />
<img src="https://www.AR15.Com/media/mediaFiles/200513/IMG-3169-109260.jpg  " />

What buffer are you using?

I think the scratches are from the feed ramps/barrel extension.

Dents are likely from the forward assist but could be from the rear of the ejection port.

I would turn the gas down slightly.

You pretty much nailed it.

Dents are common from the case hitting the deflector and will fire out.

The 2 scratches are from the feed ramps. You can take a stone or 400 grit sandpaper to remove the sharp edges.

Same goes for the extractor mark on the rim.

Nice rig !

I will have to look it up, can't recall.
It is a custom buffer and spring from someone recommended on arfcom
XH carbine 8.5oz with Wolff spring from Heavy Buffer

Thanks, I will do a lil sanding/polishing.

I think the action is  opening too soon. Turn gas off and work back from there.  

http://www.hornady.com/ammunition/superformance-in-gas-operated-firearms       

Thanks for pointing that out.
I grabbed 6 empties and viewed under magnifaction, that scratch line is consistent on all brass.
It only goes around aprox 1/2 the diameter the case, half smooth and 1/2 scratched, I will turn off gas on my next outing, and see if that clears it up.

See, this is exactly why I posted this, you guys are great.
I have gas wide open, I will shut er down and work backwards as you suggest.

With all that going on, how is the accuracy?

First outing, other than test function after the build was last week.
5 shots had a zero @ 100 and a 3 shot group of around .85-1" (didn't measure).
Used a rough ballistic table, guessing at the sight height and using factory mv numbers, gave me 10.3 moa up for 500, dialed in 10.25 and hit 3 of 3 right off the bat.

Got more ammo on the way, gonna test groups and get real data for Shooter app, using Prime 130 and Hornady 140 ELD M

Update:
Got gas adjusted.
Started at closed and progressed until I got it to lock back every time on empty mag.
Brass was fed from a Larue mag.
Piece of velcro stopped the dented brass, still need to smooth up those 2 sharp edges.

Didn't have time to shoot for groups.
These are from the last few shots after adjustment.
Thanks