That's exactly what I did, used the same bulllet seated to maximum OAL in all the rounds. Can't remember which bullet offhand, but it was in the 140-grain range--probably the 143 ELD-X. Used the standard .270/.30-06 OAL for the 6.5-06.

The 6.5 SAUM/GAP 4S also had very similar H20 capacity, within half a grain.

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