I find 40g Vmax shoot best in my CZ527. My powder of choice is 26g of Benchmark. Local RFD is currently out of the 40g Vmax, so I took a box of Scierra Blitzkings in 40g to try....it'll be interesting to see how they go compared to the Vmax. Only real visible difference is the flat base on the Scierra as opposed to the slight boat tail of the Vmax.