I doubt it will be cost effective.

Set of Lee dies £30.
Lee hand press £40 or normal press for ~£60.
scales of £15
Trickler £15
Electronic measure off £15
100 .223 bullets ~£25-£35
1lb powder ~£50
Resuse brass £0 or PPU ~£40
Primers 500 for ~£18

And that will give you enough powder for about 350 rounds.

But if you look at your first 100 rounds ~£220
Or 400 for ~£360.

I've not looked up any of those prices and bound to have missed something.

So its unlikely to save you any money but it will give you the best rounds for your rifle and reloading is a whole lot of fun. And when you add extra calibres it then starts to make economic sense.