what exactly is the difference???

i mean, a non free float setup is the threaded base of the barrel by the upper; the barrel nut screwed on that; the c-clamp; the spring pack; and the delta ring - and the two piece handguard attaches by fitting in the gas block end AND by fitting in to the inside surface of the delta ring - it does not make direct contact with the barrel. you can confirm this after putting on just one half of the non freefloat handguard and youll see it touching only the delta ring.

on a freefloat system, depending on the type, you remove everything and install a custom barrel nut or you use the stock barrel nut and in both cases the handguard mounts on the barrel nut.....and blah blah blah. and one piece or two piece freefloat.....same thing, except for gas block removal.

so am i missing something?

because what i see is that on the stock system the base of the handguard fits in to the d-ring, spring pack, et cetera, which is mounted on the barrel nut, and on the freefloat, the base of the handguard also mounts on the barrel nut!?

so in both systems the handguard mounts to the barrel nut, and in both systems the barrel nut screws onto the barrel, so in both systems the resonance of the barrel is affected in the exact same way - via the barrel nut.....

so what the hell is the difference??? 

The stock non-free float type handguards also make contact via the front handguard cap at the front sight base.  You can impart enough pressure on the stock handguards to place pressure on the barrel to create a negative influence.  Also look how people tend to mount a sling on a non free float set up.  With a "free float" forend you only have contact at the chamber area and the sling is usually connected to the free float forend and not the barrel.

jeez surf....thanks!
i was only concentrating on the receiver end and so never thought of the force imparted on the front sight end.....duh
thanks man!

By putting slight pressure on the front sight I have seen some barrels move
Shots 2". Pencil barrels move the most. Unless under the
Hand guard area is a bull barrel. 

By putting slight pressure on the front sight I have seen some barrels move
Shots 2". Pencil barrels move the most. Unless under the
Hand guard area is a bull barrel.

two inches randomly each shot; or a consistent two inches?  im asking about this for a colt M4 and 6830 and an ar10a, all with 16" chrome lined bbl. i shoot standing up with a2 front/rear so i never noticed any accuracy issues without the freefloat.... was just thinking bout freefloating one of them recently but i was never hung up on the accuracy issue w/wo freefloating

two inches randomly each shot; or a consistent two inches?  im asking about this for a colt M4 and 6830 and an ar10a, all with 16" chrome lined bbl. i shoot standing up with a2 front/rear so i never noticed any accuracy issues without the freefloat.... was just thinking bout freefloating one of them recently but i was never hung up on the accuracy issue w/wo freefloating

Depends.

Depends on how you are resting it, depends if you are putting pressure on it, depends if you have a sling and are cranking down on it, a lot of depends............  The only way you could tell with your rifle is to shoot your rifle.

Depends.

Depends on how you are resting it, depends if you are putting pressure on it, depends if you have a sling and are cranking down on it, a lot of depends............  The only way you could tell with your rifle is to shoot your rifle.

got it.....thanks

I did a test once with an (unfloated) A1 type barrel, with and without a really tight sling.  The POI moved 18" at 100yds from sling pressure alone.  FWIW, as long as the pressure on the sling was consistent, the groups were still tight, just in a completely different place. 

I did a test once with an (unfloated) A1 type barrel, with and without a really tight sling.  The POI moved 18" at 100yds from sling pressure alone.  FWIW, as long as the pressure on the sling was consistent, the groups were still tight, just in a completely different place.

holy crap.....18"!
I'll keep that in mind...
thanks!