Thats sort of a vauge question , are you wanting to use an aluminum block on the barrel , glass bed the barrel of free float the barrel? or are you talking about bdeeing the action an floating the barrel ?
I personaly like to glass bed the aluminum action block and free float the barrel.
Some guns like to have their barrel bedded or at least with a pressure point near the end and some-most shoot better with the barrel free floated , it kinda depends on the barrel size and stock desgine and how the gun is to be shot.
Now some BR guys and a couple no target shooters use a "barrel block" which is a 6"-9" typicaly aluminum block thats glued into the action and clamps around the barrel to hold the barreled action into place. With this setup say you use an 8" block and a 30" barrel , your action would be free floated and the barrel would be as stiff as a 22" because 8" of it use full supported.
Other guns have the action glass bedded into the action with the barrel free floated. The galss bedding is used to make the action to stock contact skin tight basicaly making the action and stock one piece this will help stop any inconsistany pressures in the action and keep the action from moving any. With this setup the barrel can be either free floated or bedded either fully or with a pressure point depending on how the the gun like to be.
Some stocks have an aluminum bedding block that the action bolts down into , again this is an attempt to make the action to stock fit as tight as possible. I personaly glass bed the action to the aluminum block because in mass production the fit is still gonna have some "slop" this is refered top alot of times as "skim bedding the stock".
And some stock are "piller" bedded , the use of bedding pillers is supposed to keep the action screws from being over tightened and causeing inconsistant torque on the action , to keep the wood stock from swelling or shrinking and putting uneven torque on the action. When I bed a gun wether it be composit or wood I use both pillers and glass beddding , unless the stock has the above mentioned bedding block. Do the pillers realy make a big differance? I can't prove it but my line of thought is that it can't hurt it any and I'll try anything that may close my groups or make the gun more consistant.
As for bedding the barrel , well I have seen a couple guns that would rather have pressure on the barrel rather than be free floated but not nearly as many as that wanted to be free floated. I have seen a few guns that the barrel was glued into the stock completely , free floating the action.
Barrels move alot when the gun goes off this is called "barrel harmonics" , if the barrel vibrates the same each time (proper loading) and comes to rest in the exact same spot after each shot so it can take off from the same spot eack time then it will be accurate , this is why free floating works more often than not , the barrel isin't touching anything so the harmonics are more likely going to be the same each time.
