AR15 Free Float question

[Applehaus21st]

Need help from some AR experts.

Got this Knights Armament Free Float from my buddy. He used it on his M16 A4 16" barrel set up while overseas. Before he left for deployment he gave it to me and we never got around to installing it. What parts do I need to replace so that I can use this?

This handguard is too big for the stock A1 Bushy 16" barrel Delta Ring I've got.

If you don't mind listing down what I'll need, I would highly appreciate it.

Thank your very much

[chuck762]

Doesn't look like a free float. Looks like a standard KAC RAS which just replaces the standard hand guards.

Here are instructions for the rifle length but they go on the same. http://www.quarterbore.com/library/p...c_ras_inst.pdf

One problem is the RAS may not fit heavy barrels. There is no standard for a heavy barrel diameter and some are too big.

[Applehaus21st]

Doesn't look like a free float. Looks like a standard KAC RAS which just replaces the standard hand guards.

Here are instructions for the rifle length but they go on the same. http://www.quarterbore.com/library/p...c_ras_inst.pdf

One problem is the RAS may not fit heavy barrels. There is no standard for a heavy barrel diameter and some are too big.

Your right barrel is too big cant fit this handguard. Is there an aftermarket solution without changing the barrel?

[sava6e]

Where's a pic with the free float?? Usually the free float requires removal of the front sight block and removal of the barrel nut, the free float is then shimmed and acts as the barrel nut and the handfuard all in one, then re-installation of front sight block, obviously this is a summary of the processes, point is if you have your free float then all you would need are guages, anti seize grease, shims, armorers wench, your free float, punches, mallet patience and some upper vise blocks couldn't hurt!

[chuck762]

Your right barrel is too big cant fit this handguard. Is there an aftermarket solution without changing the barrel?

You might look at either the daniels defense omega rail or a troy industries drop in rail as far as a RAS replacement. If you want a free float handguard then there are more choices but then you will need the tools to install it or someone to do it for you.

[USMG]

a good reference to keep in mind to make sure you have a free float hand guard or tube is that it touches the upper or barrel in one location not two or more. As was mentioned previously you have a standard two piece hand guard set up. A free float attaches on the base of the barrel, usually at the barrel nut and the barrel floats inside the tube then exits to a sight or gas block. Your two piece set up installs at the base by the delta ring and is then keep in place by the hand guard cap. Here is a photo of a little kitty kat 7" AR that I built a while back. you can see there is nothing holding the free floating hand guard(rails).

http://www.usmachinegun.com/proddetail.php?prod=AR-0145

Also, a two piece set up is typically a lot cheaper than a true free floating hand guard set up.