Dave,
Those BC's aren't "Spiced" up I can guarantee you that.
My Liberty's BC that I bought a while back states 300fps for my Liberty at 30"/71#.
That is bottom of the speed barrel for a 300-308 range. I saw one Liberty BC at 307fps.......But that's fine I love the bow and it shoots great.


These things are weighed on digital scales, measured, and shot.......it's tedious stuff but it's done for every bow.
If it falls within that range, it's good to go. If not, strip it down and find out why.
You could get a "Fast" one, but I think they strive to get all of them at least into the fat part of that speed range.