I have a head size gauge in 177 and the Baracuda Power I have are mainly 4.54 head size. The tin says 4.50. The Baracuda Match in 4.50 head size are 4.51 according to my gauge. I have never used any of the non-lead pellets. The Powers have a thin copper coating over a mainly lead pellet. Unfortunately while H&N pellets are well made the head sizes do not consistently match what is on the tin. Hard Air dinged them for this in a review. My P35-177 (my only 177) shoots the Power and Match about equally well but the Match are a little higher velocity and the ES is about half as big with the Match. At longer range I suspect the Match will shoot significantly better.