Who actually makes AR-15/M16 parts?

[Nightcrawler]

I've been thinking. One of the reasons so many different companies can offer AR-15 clones is because they don't have to manufacture all of the parts themselves. Oftentimes they simply finish the parts and assemble them. (Which is why, I guess, you can buy 80% AR receivers).

So who actually manufactuers all of the parts for their rifles? For the companies that don't make all of their own parts, who makes the parts they use?

 

[Bartholomew Roberts]

Well, I can say that there can often be a large difference in how companies finish out the same receivers... even at that, there are quite a few people manufacturing the raw product... off the top of my head these guys do forgings and various amounts of finish work

Alcoa
Anchor Harvey
Kaiser
Cerro Metal
Connecticut Machine&Tool
Lewis Machine&Tool

I'm sure there are more but those are the prominent ones that popped into mind.

 

[RussB]

Just to clarify...

Alcoa, Anchor Harvey, Kaiser and Cerro Metal manufacture raw forgings. No machining involved.

CONTINENTAL (CMT) and Lewis (LMT) take these raw forgings, and machine them into finished components

 

[Harry Tuttle]

i wonder where RRA is getting the chrome lining done
maybe colt?

Bushmaster does their own barrels and has the volume to own the chrome lining equipment

the trigger group and bolts prolly come from a sub contractor