What's the story behind these Colt 9mm receiver sets?

[wapiti22]

Could these upper and lower sets be made into an AR9 pistol?

[Bret]

If by AR9 you mean a 9mm chambered AR15 pistol, then absolutely. From what I've seen, AR9's have different lower receivers than these that have smaller magazine well openings for the 9mm magazines. These receivers use a magazine block instead to fill in the excess space in the AR15 magazine well. It's pretty much two different ways to do the same thing.

[wapiti22]

I ordered a set yesterday. I found all the door parts on Brownells.

What bolt does this take, ramped or non-ramped?

[Bret]

The Colt bolt is unramped, so I just ordered a Colt bolt from Brownells not knowing if a ramped bolt would work. I think that it has a 9mm specific hammer.

[usmcvet]

The Colt bolt is unramped, so I just ordered a Colt bolt from Brownells not knowing if a ramped bolt would work. I think that it has a 9mm specific hammer.

Ramped will work on Colt and Glock mags. Colt's un ramped will work only with Colt type mags.

[Bret]

Thanks usmcvet. Now I know. I received the Colt port door from Brownells and a notice that my Colt bolt shipped. Just a few more days and I can put this baby together.

[JRHorne]

Thanks usmcvet. Now I know. I received the Colt port door from Brownells and a notice that my Colt bolt shipped. Just a few more days and I can put this baby together.

About time! I'm ready to see this beast.

[Todd.K]

The Colt bolt is unramped, so I just ordered a Colt bolt from Brownells not knowing if a ramped bolt would work. I think that it has a 9mm specific hammer.

You need to use a standard AR-15 hammer that is not notched or a 9mm hammer with an unramped bolt.

[JRHorne]

Bret, its been 2 months. Give us something!

[Bret]

Sorry, the build is on my agenda. I do have all the parts and I bought a tool from Brownells to torque the barrel. I'll definitely post pictures when I'm done. I just need to take a day off and do it.