Is this normal for a Vltor buffer? I only have about 100 rounds through my A5 system. I tried emailing Vltor two weeks ago with this picture and no response.
More info on the gun bud.
What’s the upper setup with. BCG type? Piston or gas? Did you build the gun yourself or is it factory?
Is that a Vltor lower?
That buffer looks brand new minus the funky nicks.
-Jax
Factory KAC Mod 1. (KAC, gas, factory)
Everything is factory but the A5 system.
I have the A5 on 4 different rifles. One has over 2500 rounds through it. None of mine have any markings like that.
I did buy a bushmaster upper/frankengun a few years ago to part out, and the buffer (standard carbine) had those same markings, especially the lines from outer edge to center. The other markings on the edge look like it’s from the detent tip striking. I had never seen that before (except for above mentioned), and not again till your picture. Someone like IG or Grant will know what causes this.
How does the gun feel while hand cycling?
-Jax
What does the back of the BCG look like? Burrs?
Does the gun feel overgassed? Supressed?
Everything feels normal. The rifle also functions perfect. But I don’t want parts to be wearing unusually if I can help it.
The white powder wiped right off after the picture was taken.
I wouldn’t know what overgassed feels like. No suppressor action.
Eta: autocorrect fix
Racking my brain…
ETA: Dumb question but you have pulled the buffer and RE spring out and checked for any gremlins in the tube right?
-Jax
You proabally have a sharp, burred edge on the clearance channel for the buffer reatiner on the bolt carrier. Stoning the edge will likely fix it.
There is a sharp edge/burr on the back of the carrier where you found the powder.
Stone or sand it smooth.
Yep. The long scratches are from opening and closing the upper receiver as the carrier pushes the buffer back into the RE slightly. And the scoring around the outer edge is from the carrier hitting the buffer face during cycling.
Got it. Thanks for the quick solution, guys.
Yeah, that’s the one.
I had to do this on my last build.
Amazing what a little sharp edge will do.
Interesting, it must be a SR15 thing. Here is the face of my A5 after about 300 rounds.
Off topic a little but im normally not a ‘fit and finish’ guy but after installing the A5 system on my SR15 my upper and lower has alot of liner play from front to back vs the traditional side by side. Any thoughts?
THIS.
I’ve seen this before on my wife’s A5 buffer. Sand/stone/smooth that area and you will be fine.
The gouges going from the center of the buffer to the edge confirm this is the issue. Its only cosmetic. You’re fine.
EDIT: Don’t know why I bothered posting…my buds beat me to it. 
Had the exact same issue with an Armalite AR-10 several years ago. The bottom rear edge of the upper receiver would scrap against the buffer every time it was opened or closed. I sent it back to Armalite and they replaced everything that was even slightly worn and it ran like a champ. Check to see this is not the case with yours.
This works.
http://www.weaponevolution.com/forum/showthread.php?1744-BOLT-CARRIER-LAPPING-DEBURRING-PROCEDURE
So the consensus is that it’s really not a problem?
My “new” AR does it and it’s most likely from opening and closing it. Function-wise it cycles fine and it feels fine when I manually cycle the carrier. I don’t think I’ll lose sleep over it. It’s not like this will diminish the life of the buffer dramatically, you know?
There’s a lot of metal in the forend of a buffer. It will take a few million operations for it to cause a failure.
Like everyone is saying… stone the tail of your bolt carrier.