As I'm sure you know . There is great debate if barrel break in is even needed . I believe the lower quality barrels would not be hurt to be and may even benifit from a barrel break-in including chrome lined barrels . I have only did one barrel break-in and was sighting in the rifle at the same time I was breaking it in . I feel there is no need to just waste ammo . You might as well be trying to hit something while you break it in . If barrel break-in even works , It's not like the rifle isn't accurate right out of the box already .
That sure was a hole lot of words to say no more then 50 . When I did mine I used 20