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We can't estimate that, but it should be a decent jump. On the other hand, you might be put in a new bucket with having no collections on your report and your score could actually drop a little bit for a short while.
FICO scores are so hard to predict. But, if those are your only negatives and they all get deleted you should see a significant increase.
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You have the potential to see that if they are all deleted.
Here is a thread on rebucketing that can explain it better than I can:
http://ficoforums.myfico.com/t5/Understanding-FICO-Scoring/Re-bucketing/td-p/1434216