In reading some other threads talking about rails can someone tell me why free float is so great? I am wanting to do a gas piston retro fit someday and I gather that standard forearms won't accomodate the mechanism. Seems my choices are quite limited and pretty doggone expensive as well.
faawrenchbndr already answered the biggest thing. Though many will say it will make a gun more accurate, I don't exactly agree with that, though I do feel they'll help a gun shoot more consistently.
And from what I remember, the Ares and Osprey piston conversions use M4 handguards, though I think the Ares is having Daniel Defense make a semi-custom freefloated railed forend to use with theirs, but judging by DD's line, expect that to add a couple more hundred to the overall cost if you go that route. I'm sorry, but I never could understand why they cost so much.
Has anyone contacted either Ares or Osprey to find out what the minimum Inside Diameter is? I believe I saw some pictures where someone milled a railed floater to accomodate the gas piston with a notch cut out under the rail, but I can't remember where I saw it.