And so the addiction begins...

[bkoenig]

Probably not.  You don't really save any money by building your own, it just allows you to spread to cost out.

[gsd]

ahh, the upper i am looking is a core15,

16" M4 Upper receiver with a 416R Stainless Steel 3 groove Polygonal Rifling 1:8 twist M4 Barrel, M4A3 upper receiver, Midwest Industries Gen 2 Midlength (9") 2-piece Quad Rail System, Core 15 Hardcore Billet Charging Handle V.2, M16 BCG (MPI & HP Tested), and low profile gas block.

Damned near exactly what i was looking for.

[gsd]

So, built the lower tonight. what i could anyway.  CMMG skimped on a takedown detent spring so i can't put the rear detent pin in until i find a replacement.  a couple questions come to mind...

I noticed the sere was a touch off, i had to file it down a touch to fit.  Problem?

Also, the select fire pin, after detent pinning, will not move from fire unless the hammer is back.  Common?

Sorry, it has been over ten years since i had any solid sort of contact with AR's.  Fired em since then yes, but ground up builds no way Nancy.

BTW, not counting the apparently continuous interruptions tonight, took me a little over an hour to build it to where it is now.

[Dan W]

Also, the select fire pin, after detent pinning, will not move from fire unless the hammer is back.  Common?

 NORMAL on all AR15's for the safety to only operate when the hammer is back

[bkoenig]

Where did you have to file?  It should just drop in.

[gsd]

Dan, thanks.  i thought so, but would rather be certain.

Brian, It was only about 1/32 out of compliance, most likely paint/minor machining issues.  Couple strokes with a rat tail file and it pinned together without trouble.

BTW guys, little tidbit from an armorer buddy...the Spikes recievers are a Class 3 permit holders friend, if you get my drift.