I found more up-to-date data on the raw score one might need to achieve a passing scaled score in his or her jurisdiction.
Per Susan M. Case, PhD (Director of Testing for the National Conference of Bar Examiners) in a March 2011 column entitled "Common Goals with Increasingly Similar Outcomes: Jurisdiction Approaches to Bar Exam Grading, Scoring, and Standards":
While there is some variability from one administration to the next, a score of 100 reflects a performance of approximately 68 percent correct. The current standards used by jurisdictions reflect lower performance levels: 85 is approximately 60 percent correct; 80 is approximately 58 percent correct; 75 is approximately 56 percent correct. The difference between an 85 and an 86, for example, is less than one question.
(See p. 3 "MPRE Passing Standard")
Raw | Scaled Score Conversion according to NCBEX's Director of Testing is approximately:
56% Raw (28/50) = 75 Scaled
58% Raw (29/50) = 80 Scaled
60% Raw (30/50) = 85 Scaled
68% Raw (34/50) = 100 Scaled
*I guess that's why Barbri recommends the 32-38 range to be safe because it probably puts a test taker above the scaled score of 86--the most any jurisdiction requires. I broke down the raw numbers out of 50 since 10 of the questions on the MPRE are experimental.
For those of us who studied with MPRE practice exams, this might give us an idea of how our raw percentages convert to scaled scores (approximately, at least). I hope this helps.