I've got 4 of the 3 port muzzle brakes
and very satisfied with them. I don't have a 338 lupua, but I do have a 5 1/2 pound tc encore rifle in a 35 whelen. This rifle was scary to shoot in fact if you were in tree stand, and had to make an out of position shot you would probably be taking a trip to the ER for some stitches! With the muzzle brake
on this rifle, it is now very manageable. I would now take some out of position shots and not worry about getting hit in the nose, or eye.
The real reason I bought this muzzle brake is from the video. It shows it doesn't let the percussion hit you. I can tell a big difference in the percussion level hitting you with this muzzle brake.
Also Jim See gets to thumbs up. He gets you your muzzle brake fast.