Are you satisfied with the Howa mini heavy barrel?

[s3silver]

Roger that, but as an alternate theory, it could be that, inch for inch, the MV loss does not equate to staying on a node in the shorter barrel via the harmonic changes...
A powder load that hits your node for a 20" barrel most likely will not be on a node for a different length (aka Chris Long, OBT theories), that powder load will show a drop in MV at the shorter length, but the actual MV needed to be on the node at 16.5" (or whatever the new length might be), won't be the MV that the original load would give you.
In handloads you would most likely need to tweak the powder to get back to an MV that is on the node for that new length... or not and watch your shots spread out on the target...

That's a good point and observation that may be overlooked more times than not.