In general, it takes a harder cast bullet to get good results with the 6.5 Japanese. The OP said he'd slugged his bore, but didn't mention the size. Some of the earlier long rifles seemed to mostly be .2675 or more groove diameter. Take a look at the NOE website, http://noebulletmolds.com/orders/cat...x.php?cPath=27 They have a 6.5 bullet that casts at .270" on the bands. Even fits my .268 groove diameter type I. One could simply cast with a harder alloy, or heat treat wheelweight alloy. A lot depends on the velocity you're trying to get out of the bullet. The faster you try to drive them, the more likely they'll strip the shallow rifling.
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