I'd talk about sixguns and leverguns but I've got that pretty much down:) I'd like to free float my barrel but I'm not sure it's worth it. My carbine already shoots from slightly below MOA to slightly over with a decent selection of loads with MX193 usually going about 1.5-1.75". I don't like the bulky quad rails. I do kinda like the slim Midwest Industries rail. But, overall, I still can't get past the idea that the good old Milspec hand guard is simple, reliable and not exactly prone to variables like screws coming loose, etc. And, after all, if it shoots most hunting loads under an inch and 55 grain 5.56 under 2" at 100 yards, how much better do I need? I keep thinking I'd like to build an SPR upper but regardless, it's still pretty much a 300 yard rifle max. If I want that I'd just as soon grab my '06. So I'm leaning toward just popping a good Magpul MOE hand guard on it instead of a free float rail. If I do go with a free float rail it has to be tough. I don't want anything flimsy on a fighting rifle. Opinions?

If using a bipod or sling while shooting , I would go with free float. J.michael

unless you're working on a real tackdriver

Will cause your POI to shift. Maybe by a little, maybe by a lot. The better free-float setups are hell for stout; better yet you can get a monolithic upper with the forend and receiver done as one piece. Those will cost some coin though.

lot of weight for carry and quick use. No sling or such for shooting. Still have free float on other uppers.

free float tube from DPMS that threads onto the outside of the barrel nut. Light, simple and strong.

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Look flimsy to me. The ones that screw on the barrel nut look heck for stout. I'll do some looking and see what I come up with.

If so, what else do I need to buy...new barrel nut, etc? I'm pretty sure a new gas block since mine has a rail on top and the lips for the factory hand guard.

http://www.midwayusa.com/product/542759/dpms-free-float-tube-handguard-quad-rail-ar-15-...

Just tube, no rails.
http://www.midwayusa.com/product/1413269192/dpms-free-float-tube-handguard-ar-15-alumin...

All of them come complete with barrel nut.

the trendy setup now is keymod. Or, as previously mentioned, a monolithic upper.

http://www.midwayusa.com/product/2300177338/vltor-vis-upper-receiver-with-integral-free...

I get the reasoning but there is absolutely no way that makes a stronger mounting surface than an integral rail. It looks hokey and cheap to me and they are priced way above the old school stuff. I like that plain tube you posted and the only downside would be determining where to mount a sling. I could go with a single point but I kinda like old school myself. Then again, I might like it if I try it.... I think I'm gonna go with one of these two you posted after I decide whether I want a quad rail or the plain tube. I'm not big on mounting stuff to my rifle except maybe a light for hunting and that could mount to the scope easily.

Or other accessories? The SureFire mount I used over in the desert was PLASTIC.
Slings are a preference thing. The modern method is to have rifle slung across chest instead of back; either a single point (which I went with on the boy's rifle) or 2-point will get that done.

Stuff happens. I'm more concerned about a sling mount pulling out than I am my light. I'd prefer a two piece sling just so you can use it to shoot if a little extra stability is needed. And, like I say...I'm not a big fan of mounting stuff anyhow so I really don't need the Keymod or quad rail other than for a sling. I can mount a light to my scope tube...that's no problem.

If your barrel has rifle length gas and you like the standard handguard (I do), check out the national match service rifle float tubes like Rock River or Compass Lake. Here's a Compass Lake float tube on my 20" highpower rifle. It's made of steel and is as stout as a float tube can be. Handguards and gas tube are CLE also.

as in Highpower competition, then you need a free float handguard. The sling will change point of impact so unless your form is very consistent the float tube will eliminate that variable. They are trickier to install than the simple tube handguards because they have to index to keep the plastic pieces on straight and the sling swivel in the right place, and you have to get the length just right so the plastic pieces will fit properly.

The downside to all of this is that the sling swivels can break off the front of the float tubes.

It makes sense that a bipod would alter point of impact too but I don't know by how much.

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