My experience: BSF Barrels May Experience Substantial Thermal Drift.

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Here is a short article describing why they are trying to use carbon fiber for greater thermal conductivity (cooling).
When I saw the cooling slots on the BSF barrel I thought, WTF. It shouldn't need them.
Stiffness is another benefit.
https://christinedemerchant.com/carbon_c...ivity.html
Here is another manufacturer that uses continuous carbon fiber and states the benefit of increased cooling rate.
https://www.proofresearch.com/the-products/barrels/