Standard chamber - nothing custom.
COAL is 3.91"
I have a normal throat (~0.250" freebore), and couldn't seat the bullets out far enough to even touch the lands. Basically the profile of the bullet just prevents it, so a long throat would be even worse I would imagine. So I'm jumping about 0.1" which seems nuts to me.
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The important thing I've found with this combo is that I needed a tight neck tension. I'm using a pretty tight bushing to size the neck, then expanding it with a 0.3045" mandrel. The first round of load dev I used a common default neck tension, but groups/consistency weren't great. It also seemed like the bullets seated a bit too easily for my comfort, so I re-ran the same round of charges, but with the tighter neck and got dramatically better results.
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