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Posted: 9/16/2004 8:31:29 PM EDT
I'm interested in the CMMG 14.5 or 16" MOD4A3 uppers.  I'm looking for specifics on the various parts comprising this upper, and have all the usual questions of someone who spends too much time on this board.

1) Who manufactures the barrels? What type of chrome-moly is used?  Are they magnetic particle tested?  Are they Parkerized under the FSB?

2) Are the M4 feed ramp cuts done as part of the inititial manufacture, or are they done post-surface treatment (anodizing).  Anyone have a picture?

3) Are the receivers hard-coat anodized (type 3)?  How would you rate the quality of the receiver?

4) Are the FSB's forged? Are they the correct M4 height?

5) Who manufactures the standard bolt/carrier offered?  Are they head space tested to the barrel?

6) Is there an advantage to getting the full auto bolt carrier?  Is it a restricted item?

Please post even if you only have the answer to one item, but be sure of that answer!  Thanks in advance.
Link Posted: 9/16/2004 8:50:02 PM EDT
[#1]
Link Posted: 9/16/2004 9:07:03 PM EDT
[#2]
Done, thanks for the tip.  Is it ok to maintain this post on two different forums?  I'd prefer it to maximize responses, but I want to be a good little board member as well.

Edited to add: I'm unable to subscribe to the thread in the Industry forum, but I can to this one.
Link Posted: 9/17/2004 4:58:29 AM EDT
[#3]
Link Posted: 9/17/2004 6:43:24 AM EDT
[#4]
By the way these uppers rock.  There have been several reviews of them.  Since 9/13/04 mine has eaten several hundred rounds of XM193 without issue.  Its been extremely accurate and it just looks damn cool.  

I got the 14.5" with the pantom flash supressor permanently attached.  Jeff and John provide excellent customer service and shipping and with as busy as they are have always been able toget my orders to me quickly.  

These for sure have the M4 cuts and 1/7 twist.   The 1/7 twist gives you several advantages when it comes to shooting heavier rounds and stabilizes 55 grain XM193 rounds without issue.  I've only shot it out to 100 yards so I don't know how well it performs past that distance.  
Link Posted: 9/17/2004 7:47:23 AM EDT
[#5]
Any chance you will produce a midlength 1:7 16 or 18 inch barrel?
Link Posted: 9/17/2004 1:03:40 PM EDT
[#6]
i have one 16"a3 from cmmg. it's a great upper and im totally happy with it.
cmmg is a good company to deal with.


meat
Link Posted: 9/17/2004 1:11:14 PM EDT
[#7]
I have a FA carrier in my CMMG upper I bought it off a guy who had it on an RR M16, but the FA carrier is still legal. Olympic Arms shit a brick when they saw all my auto carriers when I had my Phantoms pinned to my uppers. Had to explain to them that it is legal.
Link Posted: 9/18/2004 12:07:40 AM EDT
[#8]
CMMG:  Thanks for the detailed response, you covered it all!

Combat_Jack:  Does the full auto carrier provide any advantage for semi-auto use?  I seem to remember reading about some slight advantage long ago...
Link Posted: 9/18/2004 12:13:18 AM EDT
[#9]
... FWIW, CMMG is a fantastic company to work with. They were very helpful providing my "dead AWB project" barrels. Asked all the same questions you did, got all the same answers too. So I bought.

Link Posted: 9/18/2004 9:03:00 AM EDT
[#10]
I think it is debatable if a full auto carrier is leagal in a Semi Auto.  I have all mine modified.  There is only a tiny bit of metal on the front bottom edge of the carrier that makes it an M16 carrier.  Mill 1/4" ofthis away and it will no longer make an M16 fire full auto.
Link Posted: 9/18/2004 11:29:37 AM EDT
[#11]

Quoted:
CMMG:  Thanks for the detailed response, you covered it all!

Combat_Jack:  Does the full auto carrier provide any advantage for semi-auto use?  I seem to remember reading about some slight advantage long ago...



The extra mass slows down the rate of fire and extends dwell time to increase extraction reliability.  The extra dwell time allows the gas pressure to get to lower levels so that the shell is not expanded as tightly against the chamber wall before extraction begins.  You can also get the same effect by using am H-Buffer, stronger action spring or Fat Boy gas tube.

Link Posted: 9/18/2004 5:52:29 PM EDT
[#12]
+1 on the outstanding service and product
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