Re: muzzle brake for 300 win mag
you can also try out a Ross Schuler brake ($45 shipped), works great, I have his brakes on my 450 Bushmaster, .264 LBC and 6.5 Creedmoor, little video of his brake on his .338 Edge pistol:
http://www.youtube.com/watch?v=b3pXSKpz69s