I took my new bcm out this weekend and ran 200 rounds through it but when I tore it down to clean it I noticed wear on the BCG/ Gas Key and I was wondering if this was normal after such little use?
You can notice a little bit of wear on the side of the bolt carrier key but I wouldn't be to worried about it. As long as you keep it lubed I'd imagine you would be ok.
You'll notice wear more when it's new. I prefer grease over oil on the BCG. I use high temp synthetic bearing grease from Lucas products. Way cheaper then gun grease. This is of course a matter of opinion.