AR 308 identifying issue

[gunfix]

A friend gave me a AR 308 style upper reciever in parts. It has the "built-on" carry handle and no side notch for the charging handle latch. Instead, the charging handle have a spring pushed plunger on its top that lock in forward position when it is aligned with a depression inside the receiver. The issue with all this is who makes this upper receiver?

Thanks!

 

[teddy49]

 

[pbr streetgang]

your explanation is hard to comprehend, maybe you could post a pic. the only thing i can think that you are referring to is the AR10.
does it look like any of these?

 

[gunfix]

It is the same type of upper receiver as a normal AR15 but bigger. Same charging handle, but no latch to lock it to the receiver. No markings. The firing pin is longer than the AR10. The bolt is almost 1/2" longer than the AR10. The extractor is almost like a Sako extractor but pivot and is held in place by a pin (at rear extremity instead of middle for a normal AR15). It is not a flat shaped extractor like the normal AR10 or 15. It has a gas tube just like an AR15 or AR10.