How to ID a Colt upper and/or barrel?

[spistols]

I traded a few years ago here on the ODT with a member for this Colt, and told it was Colt. I tucked it so far back in my safe I forgot about it. I am looking it over and for some reason the barrel does not match what I see other Colt barrels look like. The serial number on the lower has the LE prefix, but how can I tell if an upper is Colt or not?

 

[jdie1008semperfi]

Should be a “C” mark somewhere on it. Remove the hand guards and look it over

 

[georgiahawkeye]

Should be a “C” mark somewhere on it. Remove the hand guards and look it over

Good information to know.

 

[opps]

All Colt barrels are stamped with a “C” usually in front of the front sight tower, followed by twist and caliber, sometimes “CMB”, “C chrome bore” etc. Upper receivers can have a “C” or not - depending on year of production. Front sight towers usually have an “F” in the forging. Early thin barreled 6720s had shinny 6 hole insulated handguard’s. Some M4 6920s have cage codes.

Is there anything stamped on that barrel?

 

[spistols]

Under front of barrel it says: 5.56 NATO 1/7 CP

Front sight tower has an F on one side and on the other something that looks like <B>1

No C noted on the barrel in front of the sight tower, unless you mean front as in behind under the handguard?

I did not take off the handguard as I am an AR novice and do not have any tools or knowledge on this particular rifle.


Lower, if it means anything is a Colt marked M4 Carbine with an LE prefix serial number.

 

[davans]

Pictures would help but it sounds like a Colt lower for sure. Barrel. Not so much.

 

[opps]

Sounds like a M&A or other aftermarket barrel. Not a 6720. Twist is correct and CP may mean chromed proofed. Colt did some weird things but my 6720s are all stamped on top of the barrel.

Is the barrel is .625 all the way back to the upper or just to the front sight? Do you see the shiny insulator plate under the handguard’s?

To remove the handguards - make sure the rifle is empty, place the stock on the floor or your lap, pull down the delta ring.
How to here

 

[spistols]

Sounds like a M&A or other aftermarket barrel. Not a 6720. Twist is correct and CP may mean chromed proofed. Colt did some weird things but my 6720s are all stamped on top of the barrel.

Is the barrel is .625 all the way back to the upper or just to the front sight? Do you see the shiny insulator plate under the handguard’s?

To remove the handguards - make sure the rifle is empty, place the stock on the floor or your lap, pull down the delta ring.
How to here

Not sure what this means- Is the barrel is .625 all the way back to the upper or just to the front sight? There is a shiny liner under the handguard.

The link on how to remove the handguard- that guy is hard to watch. First two minutes is wasted.

 

[opps]

Here is a picture showing the barrel diameters and the barrel marking on one of my Colt lightweights.

 

[shootsacanon]

Do you see the numbers 13629 anywhere on it?