Anyone seen a M-4 with A2 upper?

**fowler** · 07-28-12, 07:23

A retro I am working on is going to have a A2 upper with 16" M4 profile barrel. Seems these are middle ground carbines between the Xm-GAU types of the beginning to the current M4 models. I like the A2 upper with peep sites. I found some Colt 727 pictures,but not any good U.S. information on use in service or dates.

**jtb0311** · 07-28-12, 17:45

I believe Colt model 727s were built with both A1 and A2 upper receivers. I'm not sure if there was ever an actual, USMIL designated M4 that had an A2 upper, rather than a flat top.

**Biggus** · 07-29-12, 01:37

Very early batches of M4s and M4A1s had the A2 uppers, which were replaced fairly quickly.

727s came before M4s, although they shared a few features in the early days of M4 production.

723s had A1 or C7 uppers, and 727s had A2 uppers.

**fowler** · 07-29-12, 14:55

Yes looks like Airforce GAU's company armourer would rebuild with a mix master of parts as other branchs in the teething years of the birth of the M4's. I have seen M-4 stepped barrels on A1 rec.'s to. Keep um in service and working.

**AMMOTECH** · 07-30-12, 17:02

A guide to some of the AF carbines:
http://pullig.dyndns.org/retroblackr...SAFGdeCrb.html

.

**fowler** · 07-31-12, 07:17

Nice photo's ammotech. I have been on retroblackrifles,but never looked at the airforce carbine blog,very nice. I like the oldschool airforce GAU's.

**Todd00000** · 07-31-12, 12:59

https://www.m4carbine.net/showthread.php?t=107954
Forget the CAR and the GAU, meet the GUU.

This was at the range today with an Air Force LTC it is a M16 lower, M16-A2 upper, M4 barrel and stock. They call it the Goo, he said the armorer called it Frankenstein.

Attachment 12621

Attachment 12622

**fowler** · 07-31-12, 14:45

Nice Todd,the guu and gau are kin used at same time to present. Both good carbines and still in service as you show proof of today. Mix - master Franken-carbines. Thanks for photo's

**Todd00000** · 08-01-12, 07:30

Originally Posted by fowler

Nice Todd,the guu and gau are kin used at same time to present. Both good carbines and still in service as you show proof of today. Mix - master Franken-carbines. Thanks for photo's

Did you notice the grey color of the AR-15 lower? That thing is old.