Floating the barrels usually doesn't improve single or 2 shot accuracy, but makes more consistent longer strings of shots. Floating was the "boon" of match rifles, requiring 10 shots for score + sighters.

A properly bedded rifle barrel, in wood or glass has the potential to maintain accuracy over longer strings of shots, but it is not normally the case. In the 70's when I shot match rifles, oft times the 'guys' were re-bedding their rifles as their accuracy over long strings went South.

A bedded barrel could not be trusted to maintain accuracy over as many as 10 (score) + maybe 10 (sighter) shots.

People started 'floating' sporting rifle barrels in about the early 70's to prevent uneven bedding from 'throwing' shots when the barrels warmed up.

Most times the results were amazing, sometimes not so much.

My 1939 M70 has factory bedding of perfect wood/metal fit in the action and forend. It shoots 5-shot groups into just over 1/2" at 100 meters with both 165's and 180's. I will not touch it's bedding.

Whether you float them or not is up to you. "Floating" the barrel, no matter what the calibre, can have the advantage of consistent accuracy when changing locations (countries) with different temperature/humidity levels as the wood can move a little without touching the barrel or bending it.

As Rule 303 notes, normal bedding for floating a barrel, is under the action, fore and aft as well as the parallel portion of the chamber area of the barrel.

Too, there should be no contact with the stock on the sides, front or bottom of the recoil lug.
This is how I was taught, for match rifle bedding.

edited: My .458's and .458 Alaskan shot very nice 5 shot groups or 1" to 1 1/2" @ 100M with their barrels fully bedded in glass.
Good enough for hunting.
My .375 is action bedded + 1" under the chamber. It is a sub 1" rifle with 235's, 270's and 300's, of 3 different makes of bullets. Is it more consistent - maybe. The .458 almost does that with cast, but not the .375 - oh well.