Hey guys, I could use some help figuring out which brake to use on a custom 338 RUM I am having built as a long range elk rifle. It's being built on a custom action with a 27" #4 contour Hart barrel. McMillan A3 Game Scout with Edge fill, most likely topped with a Nightforce NSX. So, relatively light compared to how most guys here would build a 338 Ultra. I don't have any experience with side-ported brakes, so I would really appreciate your input. The #4 contour barrel has a muzzle diameter of .650. That limits the muscle brake to the 3-port mini-magnum or the CSR Ø.885". Given the lighter build of this rifle, would the CSR brake be the way to go? I'm afraid the mini-magnum slabbed brake would be too bulky on the end of the thinner barrel? On the other hand, a lighter rifle could probably benefit from every bit of recoil/blast reduction that would give the edge to the slabbed brake ... Do any of you have experience with both the Muscle brake and the CSR brake? Any recommendations? So before you all get worked up about how "light" and "long range" don't work together, I am building the gun like this on purpose. I backpack hunt and want a 338 RUM that I never leave at home because it's too heavy. Fully outfitted I figure the gun will weigh somewhere around 11 lb. I understand that the gun will be too light to fully utilize the long range potential of the round, I just love shooting 338 bullets at elk, and I'll be able to carry this gun all day and hammer them as far as I'm comfortable shooting the gun.