Are there any members who have a Colt 6721 Tactical Carbine with a stepped ( cut-out for accessories forward of the front sight as with the 6920 ) barrel as originally supplied by Colt? My understanding was that this model is supplied with the heavy barrel without accessory cut-out. Anyone have any experience with this? 
I bought a new 6721 not quite a year ago and it has the heavy barrel just like all the Colt literature said it should, I have never seen any other barrel profile offered on the 6721. But hey you never know stranger things have happened.
Iām sure there are alot more knowledgeable guys than me around here maybe someone else can chime in with more info.
WLP, how have you liked the 6721? I already have a 6933 and am wanting a 16" rifle. Am debating between the 6721 and the 6920. Any words of wisdom on that model?
I shoot both 6721ās and 6920āsā¦I like both. Hey!!! They are Colts!!!
I like the rollmark of the 6721 āAR15A3 Tactical Carbineā
over the 6920ās āColtās Law Enforcement Carbineā. Most of us pull
the handguards, so unless you need the 203 barrel cutā¦
Iād take the 6721ā¦you can find them for $100 bucks (or more) cheaper too.
Thanks $2ā¦ how would the difference between the 1/7 and 1/9 be if it even matters? I have the 1/7 in my Commando and can only think it helps just due to the fewer inches in the barrel.
I do have to say I am starting to like the heavy barrel (simple) profile in lieu of the M4 profile on the 6920.
I keep forgetting about the barrel twist differenceā¦
As far as I know the 6721 is Coltās only carbine with a 1 in 9" twist.
ZGXtreme,
I have almost a 1000 rounds through the 6721 so far and all is well, I removed the factory handguards and replaced them with a MI # 17 rail , Aimpoint ML-3 in a Larue cantilever mount and I am running a Surefire G2 in a Viking tactics mount, Right now I am also running a ARMS 40 buis and a VCAS sling. I am upgrading the buis to a Larue as soon as funds are available. I dont really notice the barrel weight difference because we have 20" HBAR rifles at work, I guess you get used to the weight? And finally like twodollarbill said the 6721 usually run about $100.00 cheaper than 6920ās
The current fashion trend in ARs is light barrels and 1/7 twists. So if you go with the 6721 you run the risk of being an outcast! 
I have a 6721 because I have no use for a 1/7 twist barrel, and Iāve never been bothered by the extra weight of the HBAR.
If you find a 6721 with an M4 type barrel, itās not factory.
Thank you for your replies. It turns out this newly purchased rifle does have an M4 upper as supplied by Colt although as an error on their end. Customer service was very accomodating and have offered to replace the M4 upper with the correct 1/9 twist HBAR. What would you do? Keep the M4 on the AR15A3 lower, or go with the HBAR? Any downside to keeping it as is?
Keep it as is!
Iād keep the M4 upper, I donāt care for HBarās, and I havenāt enountered any issues shooting 55 gr. ammo in a 1/7".
Talos, whatās the twist rate on the M4 profile barrel that your weapon came with? 1/7 or 1/9?
Kisara, twist rate marked on barrel is 1/7.
Let me know if you want to sell the 1:7 upper or complete rifle.
- No buying and selling outside of the E&E per site rules. 2. Situational Awareness is paramount. You posted in a thread that is 6.5 years old. What do you think the odds are that he may not have it?
Post #1 for this guy to bump a thread from 6.5 years ago??
At least he was using the āsearchā function.
my apologies.donāt get your panties in a bunch!
Markm,
ever make a mistake before?
its sarcastic b******* remarks like that that keep me on other sites versus this one