“New” old Colt 9mm AR

[Chuck R.]

The factory ones I tried had bad bullet setback... maybe the crimp isn't as snug as yours.
Be that as it may... just watch for it if anyone is using the same factory load.

I just re-looked at your images.

Honestly I think you have a feed issue.. mags or geometry IF you're getting that kind of setback with that variety of ammo. My AR6951 for instance hasn't had an issue with V-Crowns, GDs, and even 147grn FP coated bullets.

What mags are you using?

 

[GE-Mini-Gun]

Am I seeing this correctly? Is that a "third" hole above the trigger pin?

 

[Lefty38-55]

I always loved the thin mag poking out of the 5.56 sized magwell, it just looks like it means business. ...

Like this?


Buffers - I run the 9mm-Q-Buffer from 'Heavy Buffers' in my old, but upgraded, Olympus setup with Sten mags. Link = https://heavybuffers.com/9q.html

Sight-In 9mm PCC, link = https://www.thehighroad.org/index.php?threads/25-yd-zero-for-a-9mm-carbine.923956/

 

[PO2Hammer]

FWIW... 129 OEM 9MM loads chrono'd from my 16" Colt Pattern PCC
Avoid Alum. cased ammo, avoid coated bullets, and frankly none of the SIG V-Crowns would function... all those had serious bullet setback. ( YMMV )

If it were me I would be very concerned about that.
I agree that you may have a serious issue.
Worth a thread of its own.

 

[bfoosh006]

I just re-looked at your images.

Honestly I think you have a feed issue.. mags or geometry IF you're getting that kind of setback with that variety of ammo. My AR6951 for instance hasn't had an issue with V-Crowns, GDs, and even 147grn FP coated bullets.

What mags are you using?

MetalForm 32rd and 20rd mags... and fwiw, the other 120ish different Factory loads worked fine.

It could very well be my setup, the SIG V-Crown's would consistently do it. All the 3 different weights. I was a little let down, by the V-Crowns. That big'ol HP showed promise given the added velocities.
They would snag at tip of the HP. It might be the feed angle from the Metal Form mags.... FWIW, I tried the ASC versions, and those did not like my setup... lots of misfeeds.

It has run many thousands of rounds since that chrono test. Only one bloop round ( Winc. Super Clean 105gr ... no powder in one round )
To bad, it was shockingly clean running... fired cases looked like freshly cleaned cases.

 

[PO2Hammer]

The mag release cuts might be off, causing low rounds.