What barrels are you guys using for an xm177e2 clone?

http://www.brownells.com/rifle-parts/barrel-parts/rifle-barrels/ar-15-retro-barrel-line-prod77794.aspx?avs%7cMake_3=AR-15


Haven't done so, yet. But in other threads this is the one that got pointed out to me. I guess if you're really ambitious you can buy a real nice DD or BCM barrel, and then have it cut down and turned down to pencil profile, by a gunsmith. To the correct dimensions.

As already pointed out, the Brownell's retro barrel is a good choice, but there are a couple of things to consider.  First of all the handguard cap is incorrect for any of the carbine builds that require the round handguards.  The barrel comes with a triangular cap that will not work with the round carbine handguards.  It's a simple $5 fix, but it's annoying they got it wrong, especially since the only handguards that will fit the supplied cap are the shorty triangular ones that are only correct for the 607.  Just keep in mind that you will need the round handguard cap that will fit the 0.625" barrel diameter at the gas block, not the .750", although you can make it work if you have to.

Replacing the handguard cap is a piece of cake with these barrels.  The tapered pins tap out easily from left to right and are just as easily reinstalled.  Just make sure that you use a brass hammer and good drift punches to avoid finish damage.

Brownell's elected to use the 1:12 twist rate, which is correct for most of the carbines, but it limits ammo selection to the 55gr bullet weight.  Not a big deal, but something to keep in mind if accuracy is a concern and you want to use heavier bullets.

Brownells's also stocks a very nice moderator replica in the correct dimensions.  I can't compare it to Brick's or anyone else's because I don't have direct experience with them, but this is a very nice repro.  I think it's $49 or so and includes the grenade ring.  If you permanently attach this "moderator" to their 12.7" barrel then the OAL will be a little over 16".  If you decide to go the SBR route then you just have to shorten the barrel to 11.5" and thread it on.