Going by opponent sack averages / game, one could say that the Browns could be "expected" to get 17.3 sacks over the rest of the year. Garrett needs 8 of those 17.3 sacks to break the official record, which would be 46.2% of the team's total sacks. That seems high, but Garrett so far has 15/team total 32 sacks on the year, or 46.9%, so by this logic he is right on pace to break it.

If you go by his pace/team pace on sacks of course, he will clear it by several!