I'm thinking about getting a new upper for my CAV-15.  I'd like to get an A2 with full front sights, and a free floated bull barrel.  Some of my concerns:

1) I'd like the rifle to be light in weight.  It is actually for my wife so weight is important.

2) I'd like to be able to attach a harris bi-pod to the handguards to keep it "free floated".

3) I'd like to have it as accurate as possible but accuracy isn't the end-all.  So here in lies the title of the thread.  What are the accuracy potentials of the 16, 20, and 24 inch bull barrels?  What are the weight differences between them?

Any advice as to options, manufacturers, etc.. would be appreciated.  BTW I like the free floated handguards with the rails on all four sides by Fulton Armory.  Are there any other similar hg's out there?

Get a Bushy in 16", ltwt or M4 profile.  I regularly put 9 of 10 into a combat silhouette at 300 yds with a 16" 'no-name' with cheap ammo. IMO free float is not necessary for a combat rifle, there is always the possibility of foreign matter in the handguard.

It has a 16" A3 HBAR on it now.  How does one id the manufacturer of an upper?