9mm ar problems

[IEatZ28]

I ordered the complete upper, its a RRA upper in 9mm, only problem is the 9mm LPK conversion is OOS and is now discontinued, i had one ordered and it was in stock, i placed my order then i got an email 2 days later saying its backordered.

Now i have no where to go. I cant find a lower parts kit for 9mm, and im not even sure the difference but if anyone has any idea please let me know i dont want to waste the 9mm upper.

What parts do i need that are different from a standard 5.56 lower parts kit?

I really just wanted a 9mm carbine but i just got a sterling so the bug is kind of gone but i have a 9mm complete upper and a lower ready to go, but with no where to go.

[Fozzie TheBear]

Everything is potentially the same depending on your lower setup and bcg. Potential variables are hammer and bolt catch.

I run a PSA magwell adapter with a New Frontier BCG in a lower with a standard lpk

Depending on your lower you might need this stuff....http://smftactical.com/9mm-builders-kit/

[FIREBALL_BRIAN]

same lpk as anything for AR15.

diff is if you have a ramped or non ramped bcg. As you will need a specific hammer only.

[meanrock]

I'm not 100% certain but I believe: Unless you have a 9mm lower you will probably need a magazine well adapter with an ejector; Then a 9mm buffer and tube or adapter, and possibly a different hammer(this depends on bolt). All the other stuff in the lower- trigger, pins, grip, safety selector etc should be the same.

[xxINKxx]

I have a RRA upper.

I bought a dedicated 9mm hammer at brownells since the rock river arms needs a dedicated hammer due to the bolt design. Rest of the lower parts is the same. Run an h3 buffer, and do the spacer mod in the buffer tube since 9mm round is shorter and the buffer doesn't need to travel all the way down the tube. Get a Hahn drop in 9mm adapter for the lower if your building off a standard multi cal lower.

[afteractionreport]

Depends on what kind of lower, bcg you want to use?...

You can have a milspec lower with a 9mm magwell block, ramped bcg and with the use of a ramped bcg you can use any milspec lpk. If you dont use a ramped bcg(milspec) instead then you will need to use a 9mm specific hammer instead of a milspec one.

There are also dedicated 9mm lowers that do not use magwell blocks. Like glock style ones.

Most 9mm AR come in two flavors. Either a colt style mag or a glock mag lower.you need to decide what kind of mags and lower you want to use. If you go colt style then you need a colt style magwell block if you go glock then the same applies.

I have a colt style CMMG UPPER and milspec lower that accepts colt style smg mags or modded uzi mags. I like having the lpk milspec so incase i want to ever swap out upper back to 556 caliber then i can with relative ease...

Browse this useful thread

http://www.calguns.net/calgunforum/showthread.php?p=18972394&highlight=9mm+ar+thread#post18972394

[afteractionreport]

Or ask me any question i will try and help as much as possible...

Im more helpful with Colt style 9mm ARs but can answer some basic glock questions too

[THEJAPINO]

As far as LPK related 9mm parts go, if you are using a ramped 9mm bolt, the standard hammer will be fine. If you're using a standard mil-spec lower, you'll need a 9mm magwell. Installed in that magwell will be the feed ramp and ejector, both 9mm specific. Then depending on which 9mm magwell you decided on using, it'll either use a standard mil-spec bolt catch or a 9mm specific one.