Dave I thought about doing the same thing. Did find this little bit of info: 24" barrel Hornady 200gr 2500-2800fps,using 44.5-46.0grs Accurate 2015. Hopes this helps. Why not just build a 358 Winchester, it uses the same case basically (a necked up 308). A bit over 2100fps with a 250gr from 22" also 300grsp with 43grs. IMR4895 around 2200fps from 24".