I've emailed H S twice, but still no answer. I'm trying to find out the barrel channel size. Do any of you guys have the pro series sporter stock? I'm trying to find out the biggest barrel I can shove in there. I don't mind hogging out the barrel channel a little. I was hoping to fit a Remington heavy varmit, if not the smallest I want to go is a #6. By the way the rifle is a Ruger M77 mark 2 in 300 win mag so my options are limited. I thought the H S would shoot a little better than a Hogue stock.