Bedding the action can be done with pillars or with just acraglass from Brownells. Neither bedding or floating is necessary if your gun shoots fine as is.....but many don't and if the lack thereof is the cause, you can try ammo until the cows come home and you'll not get anywhere.

DON'T DO THIS WITHOUT COACHING!!!!!!

Glass bedding is the process of applying an epoxy between the stock and the action and allowing it to harden such that the action perfectly fits the stock and that no forces exist to warp the action.

Free floating the barrel is the process of shaving the stock in such a manner that the barrel don't touch the stock anyplace. Any contact of the stock and the barrel will result in a vibration of the barrel during firing that is not uniform and can easily result in serious inaccuracy.

Neither of these things are required.....many guns shoot fine without.....but if your gun is shooting poor groups, these things must be done to eliminate the bedding of the action and barrel from the equation.....and then you can work on the ammo.