So I initiated this build after building my own .223 5.56 build AR, however I posed another project on myself.  I bought a multi cal. Aluminum billet Lower receiver only, nothing else.  So I pose my question to you, what do I need for the complete lower?  The upper is a separate issue and my concern only lies with the lower being completed.  Can I use a standard lower assembly trigger kit?  What's the difference I will see in parts needed.  As well because it is a multi.cal. I would want the option of being able to switch out the 9mm to a .223 5.56 setup, and I'm hoping the lower parts will able me to do so.  Please let me know.


Thank you,



John

Here is a recent thread in the pistol caliber forum with some info for you.

http://www.ar15.com/forums/t_3_15/629999_Quick_Questions_About_9mm_AR.html

Appreciated.  Spoke to a very knowledgable 9mm colt style AR dealer yesterday and wow.  I now have an almost practical universal complete lower to swap in and out both 9mm & .223/5.56 uppers with ramped bolts with the exception of one part to make it all happen, the mag block.   Again thank you

No need to Thank me.  That being said,  you are very welcome.

Im glad to hear you found a build path you will be happy with.

Just wait till the BRD sets in again...