PDA

View Full Version : Free floatin a barrell


danl
January 27, 1999, 05:29 PM
Somebody help me. What does it mean to free float a barrell ? Does this help accuracy ?
Is it something I can do myself on an old wood stock Ruger. Thanks.

Mikey
January 27, 1999, 07:26 PM
Free floating is the removal of material from the part of the stock that would normally be in contact with the barrel. This would begin at the area immediately in front of the action and continue all the way forward thru the forearm. In most cases it will improve accuracy by eliminating possible inconsistant contact between the stock and barrel. Only remove enough material to prevent contact. You can test it by sliding a piece of paper between the stock and barrel. You may want to glass bed the action so the stock/action fit remains stable after the floating operation.

If you free float the barrel on a Ruger, there will probably be a dramatic shift in point of impact since the forward action screw is diagonally placed to actually force contact between the barrel and stock. Ruger's theory was - if the stock is going to touch the barrel then force it to touch in a predictable manner - works pretty well but his best guns are free floated.

One more option is to totally glass bed the action and barrel which creates total contact between the barrel and stock. This will also usually improve accuracy even though it's the opposite of free floating. Remember, the aim is to make the gun behave exactly the same each time it's fired, either by eliminating contact or forcing consistent contact.

Hope that helped.

Harley Nolden
January 28, 1999, 05:17 AM
I agree with MIKEY: However, it will depend upon what the rifle is going to be used for as to how much wood to remove. Hunting rifles can be relieved to the "paper sliding" technique. However, if it is a competition gun, more wood needs to be releived for the increase in bbl size due to heat.

The reverse, (full channel bedding) as MIKEY states is also great, however, I have tested this method quite extensively to discover, in most cases, that the group will shift after about 5-6 shots.

The forearm screw on the Ruger, adding pressure to the barrel, is a good system. However; after extensive testing I discovered that the pressure on the barrel is a marrying situation. That is, some barrels require more pressure than others. Again, a marrying situration. This system is incorperated on the Mauser, .308 located on my home page. Using this system, barrel pressure, produces cold shot groups of 1/4" @ 100yds. (earth level machine rest) Again it is a marrying situation and the amount of pressure will vary with the barrel. Even the same type of barrel in a different guns will not be the same.

HJN

Harley Nolden
January 28, 1999, 05:18 AM
The home page with the .308 is located @

http://members.tripod.com/~stock4broker/Firearms.html

hjn

.
January 28, 1999, 08:55 AM
Danl,
I think you've got the picture by now. Precision is a machine function. To optimize it you must minimize all affecting variables. Barrel harmonics are consistent if all other variables remain the same when free floating the barrel. The change in barrel temperature (also influenced by ambient temp) can dramatically affect the harmonic waves in a free-floated barrel, consequently making a significant change in the bullet point of impact. A key is to "dial" in for the conditions under which you expect to shoot. If you're going to shoot lots of strings, then dial in when the barrel is hot and use a series of warm-up shots before shooting for precision. If you're gonna carry it as a hunting rifle, dial in for cold shots, 'cause most times you'll only get to shoot the first shot. Some would say that's all you need anyway. :)


[This message has been edited by Mykl (edited 01-28-99).]

danl
January 28, 1999, 04:13 PM
Good information guys. Thanks.