I would just make sure to clean it before you fire it for the first time. With both of my 223 rifles I did not perform any kind of break in procedure. I cleaned before shooting. On the 700LTR I did a quick patch cleaning after a few rounds and then continued on with the range session and cleaned afterwards.
My .223 Rem 700LTR is nearly a year old now and the last time out I fired my two best target groups ever with any rifle. And the rifle had not been brush cleaned for close to 50 rounds before that , only patch/solvent cleaned.
In my case I can't see how a clean and shoot clean and shoot break in would have accomplished much.
However ,if it gives you peace of mind doing it then by all means do it. Myself, it just takes away time I could have been shooting.