So i am debating buying this Barrel for my Colt 6940.

I really like the shorter barrel and i have always hated the standard front sight on the 6940's. i know the A2 front sight is probably considered a downgrade but i really like the way they look.

The problem is i fairly new to the AR world. i have had this gun for about 5 months now. i know a lot about AR's but i have never worked on them, just basic maintenance and cleaning.

What all do i need besides the barrel? CMMG offers a number of add ons:

Delta Ring assembly ($11.50) i dont think i need this because i have a free float assembly, but would like to know if im wrong...

Front sight Gas block 2 options: .750 marked ban compliant front sight base CBP (+$45.00) or Micro Gas block (+$60), i really want the A2 style front sight so i should go with the first one right?

Sling Loop and Rivet (+$2.50) what is this and do i need it??

Gas Tube and Roll Pin (+$12.50) do i need this?

Bolt Carrier Group: Bolt head spaced to barrel (+59.00), Bolt head spaced to barrel semi auto (+159.00), Bolt head spaced to barrel full auto (+159).... i dont think i need any of these but please tell me if im wrong


Also, how are these barrels? i know Colt barrels are solid so im not sure if its even worth the change. i think CMMG is a respectable brand but they are clearly behind colt IMO. do you guys think it is worth the upgrade?


And last question, Do you think this barrel will fit my current Hand guard? if it doesnt im definitely not going to buy it... i emailed CMMG but havent heard back form them.
Thanks for the help in advance!


Also this is my first post here, i have been lurking for a long time and finally decided to make an account.

Here is a pic of my current build:

http://i44.tinypic.com/3entf.jpg

Cheers!

I believe both the barrel nut and barrel extension are proprietary on the 6940 and require a special tool to remove the nut. That CMMG barrel is not going to fit on there since it has a standard AR-15 barrel extension. Not worth upgrading in my opinion as the cost of everything far exceeds the benefits.

No way I'd defile my colt like that.  I'd send it to adco and have them chop your barrel down and perm attach a vortex or something.



But it's your gun and free to do what you want.

Thanks for the input guys, just exploring my options.

Can you expand on that? do you know the cost? also i heard that the front sight is not removable on colts is that true?

Thanks!

I would look at PSA for a new upper because if your replace the barrel the colt 6940 has a monolithic upper and would not cover a midlength system and you can get cheaper mil spec parts for PSA  but then you need a new rail even though you have nothing on the rail. I would kept this setup because colt make probably one of the best barrels around and you really only lose 1.5" off the barrel plus the perm flash hider means no changing it  later on.  Save your money for a SBR in my opinion.

send to ADCO and cut to either 14.7 and permanently install the A2 birdcage or 14.5 and install a phantom or vortex or battlecomp.

Delta Ring assembly ($11.50) i dont think i need this because i have a free float assembly, but would like to know if im wrong...

Front sight Gas block 2 options: .750 marked ban compliant front sight base CBP (+$45.00) or Micro Gas block (+$60), i really want the A2 style front sight so i should go with the first one right?

Sling Loop and Rivet (+$2.50) what is this and do i need it??

Gas Tube and Roll Pin (+$12.50) do i need this?

Bolt Carrier Group: Bolt head spaced to barrel (+59.00), Bolt head spaced to barrel semi auto (+159.00), Bolt head spaced to barrel full auto (+159).... i dont think i need any of these but please tell me if im wrong
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Buy a new A3 Flat-Top upper receiver for $100 from somewhere..

You don't need a delta-ring if your adding free float assembly.. again depending on the rail you want.. some need them.. some don't... A long FF like a Troy Alpha uses just barrel nut (which they include).. you didn't say what type of free float you have..

The micro-block would be used if your freefloat is long and would normally exceed the length of the gas system.. so with midlengh anything over 9" for a handguard will run right into your planned A2 and you would need the micro-block..

Your A2 front sight you may get probably has the holes for the sling swivel.. do you want a sling up front option for $3..?? I would get that if you go the A2 FSB route..

Your current Colt is a Carbine with Carbine gas tube.. so yes you would need a gastube and roll pin for the mid-length gas system barrel..

Just buy a LMT or DD BCG from RifleGear or somewhere.. your not assembling it.. so headspace on NEW barrels and uppers is almost a non-existant issue.. and $160 for a BCG is crazy.. IMHO..

If you basically have ADCO build your upper you can keep your Colt upper or sell it on the EE (Equip Exchange)  AFTER you test the newly built upper your planning on to see if you really like it..