Make you own OAL case by sizing one, cutting two slits in the neck with a Dremel and cutoff wheel. Slide the bullet you want to measure the OAL and carefully chamber/extract the round and measure to the tip. This will put you close enough for a general Over All Length. You really need to get the Hornady attachment and collets for a dial caliper to be able to correctly measure to the ogive of the bullet. Your barrel should be 1 in 10 twist.
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