I got my smoke pole out yesterday (T/C Encore FX Pro Hunter) and chrono'd some 205gr Barnes T-EZ. I let the gun and components cool to match ambient temp of 45F. I got 1988fps average. 84gr by weight BH209. I thought that a little slow, so I tested the BH209 volume tubes and my brass volume charger. 120gr by volume of BH209 came in at 96gr by weight every time I tested it on the Chargemaster 1500. So, I don't think the 70% rule of Volume to grain weight applies to BH209. Possibly because it's extruded?