Sorry they were such poor help. The best way is to get the ogive positions to match where they touch the lands, but unless you have the TSX on hand, you don't have that option. On the assumption the ogive shapes are very close to the same, you could go by seating depth. In this case, you can measure the average length of the TTSX bullets. Then call Barnes to ask what length the TSX HP is? Subtract that length from the TTSX length, and add that difference to 2.180". See how that fits?
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