Tried to contact the custom bbl company about the bbls neck dimension, but was told to go to a forum and contact a member who knew a lot about it ?????? Never had such poor customer service ever from a weapon oriented company.....but, won't do it again. I plan on shooting out to 600 yards using either 105gr or 95gr bullets....anyone that has one and shoots at distance have info on powders or tricks for this cartridge. Is a 24" bull barrel, on a Vltor upper, adj gas block, and threaded for a can. Does this cartridge have common chamber dimensions, and does anyone know the neck diameter ? Thanks for any info or help...rsbhunter

Try here. It's an old thread, but has good info.