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If you are planning on reloading for the .223 then 100% load for the swede.
It will give you much more control of your ammunition supply (provided you are happy to buy consumables in relative bulk) and will more than likely increase the accuracy, ballistic and terminal performance of your rifle.
6.5x55 is a bit of a tricky one, there are generally 2 sets of data, 1 for older weaker service rifles and one for modern rifles, marked SE or SKAN that can run at higher pressure.
If you have a modern rifle then use the latter to get the most out of the cartridge.
Some people will take this a step further and load to creedmoor or even .270 pressure levels which are higher than the SE/SKAN maximum and get even more performance. This is possibly safe as the same actions are used for the cartridge and good quality brass, think lapua/norma/Nosler will cope with the higher pressure. As a new reloader this is NOT a good idea, you have no way of actually measuring the pressure, you can only read the signs set out in any good reloading manual. So stick with the load data for the cartridge and stop before you get to/ drop back from any pressure signs.
Before you do anything buy a decent reloading manual, read and understand it. DO NOT use data or advice off of the internet, as a new reloader you won’t know how to decipher the good advice from the bad. Reloading is perfectly safe if you do it and follow the process and data correctly, if not you can blow your face up or injure someone stood next to you.
As a case in point, I recently saw a rifle blown into several pieces, and I mean multiple pieces, because the person loading used the wrong powder for their rounds. They luckily got away with just needing new pants, but you effectively have a pipe bomb mounted in your shoulder with your face at one end. Follow your manual, data and process correctly and this will never happen to you.