Upper ID help please

[The Extractor]

Hi, I was given an upper and Im not sure of the make.

It looks like a heavy wall billet
no forward assist
a 9 mm deflector and door
Large front pin hole
no markings, other than an "A" on the back side of the rear pin hole.

Any leads appreciated.

[kidicarus13]

How about posting pictures.

[The Extractor]

http://i.imgur.com/Uewt9Z1.jpg (https://imgur.com/Uewt9Z1)

http://i.imgur.com/BDRJIUK.jpg (https://imgur.com/BDRJIUK)

http://i.imgur.com/GLXaoRV.jpg (https://imgur.com/GLXaoRV)

[Great-Kazoo]

Well it's not a dedicated 9mm since there's a gas tube hole in it.

Could be RR, or CMMG with that 1/2 ejection port / brass deflector. Do you absolutely need to know who is came from?

[Skully]

Was the enlarged front take down looks like it was made for an old COLT lower when they did their little stinking to make sure only their uppers worked.

[The Extractor]

Thanks everyone.
It is not critical that I know just curious as to what is I have.