Hello all,

First off, let me thank you in advance for your advice/help :)

I did try to search the forums (as any forum newbie should...) but I didnt find anything on building out a 458x1.5 (also called 458x1.5 Barnes)

I've got a 110 in 300 Win Mag that I'd like to use as a donor action, and here is a small list of questions that I've come up with so far:

  • Has anyone bought a breech threaded barrel with a .458 bore (but not chambered) and if so, from whom?
  • Instead of renting or buying a reamer, could I just bore/machine the chamber? I have a suitable lathe.
  • What twist rate would you recommend to stabilize ~300 gr bullets. A bit of light research looks like 1 in 12" or 1 in 14" twist rates.



There are plenty of down the road questions about headspacing and feeding from a long magazine with a short round and.....
but for now, anyone got any advice to get me out of the gate as far as buying he necessary raw materials?

So thanks in advance, and apologies for dumb newbie questions you're likely to get if you respond :D

Thanks again,
Dave