AR-15 FreeFloat Questions

[Binaryenemy]

Ive heard a few people ive come in contact with since getting my ar-15 complain that the barrel can flex due to having a freefloat. Is this true? What type of flexing do they mean and is it harmful? Also any suggestions on a budget railed car length freefloat? Thank you in advance for any and all info

[Decholder]

That would only happen if you are shooting a tremendous amount of ammo through it in a very short time, but if you were to experience this with a free float system, it would be even worse with a standard DI rail (the extra weight on the barrel itself). As for good free float systems, there are several out there, but I think the general consensus you'll get is that Larue and DD are the best. I prefer the Omega rail by DD because it doesn't require any mod to your weapon. Hope this helps...

[xd40_jim]

Don't know anything about the barrel flex, but if you are on a tight budget, I bought UTG quad rails for my AR and they are tight, with no movement. I was on a real tight budget, so I couldn't afford the better name brands. Got them for $60. Haven't had a single problem with movement. They are a tight fit to get in and have a set of screws to hold them together. The only thing is they are kinda bulky, and with the rail covers, they are even worse, but not unmanageable. I want to get a set of ladder rails to replace the rail covers that came with the set.

[Decholder]

Here's some more explanation on the barrel flexing

http://hunting.about.com/cs/guns/a/float_bed.htm

Why float a barrel? Well, when a rifle barrel heats up due to the high temperatures resulting from firing a cartridge, the metal naturally expands. Pressure on various points along its length from high spots in the stock's barrel channel can cause the barrel to bend ever so slightly as it heats up, which naturally may cause bullets to fly someplace other than where the previous shot(s) went.

Since a floated barrel doesn't touch the stock along its length, that variable is removed from the equation. Sometimes it works to improve repeatable accuracy, and sometimes it doesn't. Floating is at its best when used with rifles that have relatively heavy (large diameter) "bull" barrels, because they are less flexible than slimmer barrels. Lighter "sporter" barrels are less stable, and may flex enough during the shot that accuracy will suffer.

[DPB]

It depends on what you are doing with a given rifle.

If it is an SPR, DMR, match, or varmit rifle, which will be fed match ammuntition, then free floating will allow you to get the maximum possible accuracy out of the rifle.

If it is a utility rifle, which will be fed surplus grade ammuntion, the benefits will be less noticible, and less important for the rifles intended tasks.

The only real negative is the icreased cost of components. The degree of positive change will depend on what you need out of the rifle.

[Binaryenemy]

Thanks alot for the info on the flexing, i wasn't sure what they meant by it. Ive got a new question now that came to mind. I scoped my rifle and use it to shoot paper people long range. Ive got a Versa Pod that goes on my bayonet lug, with a free float will that put more strain on the barrel then reg hand guards? I don't heat the barrel up with loads of ammo threw it or anything.

[Decholder]

If you're going to go through the trouble of getting a free floating barrel, then you're not going to want to attach anything to the barrel itself. You should probably get an adapter for your bipod so you can attach it to your rail system, to stick with the free floating theme. But then again, if you decide not to go free floating, then it sounds like the way you have it set up is fine.

[BerksCountyDave]

Thanks alot for the info on the flexing, i wasn't sure what they meant by it. Ive got a new question now that came to mind. I scoped my rifle and use it to shoot paper people long range. Ive got a Versa Pod that goes on my bayonet lug, with a free float will that put more strain on the barrel then reg hand guards? I don't heat the barrel up with loads of ammo threw it or anything.

If you go with a free float rail, this is the bipod/mount you want:

http://stores.homestead.com/Laruetac...ail.bok?no=172

[Lycanthrope]

You aren't going to bend an AR15 barrel with or without a free float tube. Take one off....try it.

On a bolt rifle the forearm is independent of the barrel so that barrel can be supported by the stock. On an AR15, the barrel is connected to the receiver by a nut and this is the SAME whether or not the barrel is free floated. There is no extra support because everything is hanging on the front of the upper receiver regardless.

I've had positive benefits with free floating AR's and using handloads. Rifle barrels ring akin to a bell when you fire a round and you want the same tone every time for consistency. If you have anything attached to the barrel that varies pressure then the barrel will resonate differently and impart that to the bullet.

Lycanquitworryingthrope

[DPB]

The issue isn't bending the barrel, the issue is flexing the joint of the steel barrel and aluminum receiver.

If the barrel is not floated, pressure near the forward handguard of the barrel (from a sling or VFG, for example) has a lot of leverage to flex this joint. remember, it only takes a miniscule flex to change POI.

If the barrel is floated, the pressure is much more isolated.

At least, that's the idea. The execution depends on the quality of the parts and construction.