I wouldn't, they make 7mm (.270) bore snakes that would be better suited. The .30 caliber brush is going to be really tight in that bore and may run a risk of eroding the crown with excessive use. Besides, patches will clean the bore properly themselves.
Sorry to go a bit off-track here, but are you recommending not using brushes in general? I use brass brushes for cleaning all my rifled gun barrels...just wondering if I shouldn't be.