The muzzle break still seems to have too many of your polygons; keep in mind that it's the most distant part of the model in FPS view. The layout of the polygons for the scope lens really doesn't make much sense. A standard disc layout would use fewer polygons and allow you to actually model the subtle concave surface for…
Buttstock, pistolgrip and muzzle are all areas you can cut quite a bit, then put those tris back into the Scope. It is a key feature in FPV and really needs to have a lot of edges to sell it being cylindrical. Baking the rails could also be a option if you need to cut tris. Take a shot from the First Person View also.
On top of what Shrike said that scope is not going to bake well at all. You are going to get all kinds of waviness and artifacts because of how different your lowpoly and highpoly are in that area.
Like others have said some of your cylindrical objects still have too few sides. Keep in mind with this next generation rolling in round objects should be very round, no visible facets on cylindrical objects up in the players face. The scope is better in your latest iteration but the bolt could use some more sides. Also…
I finally baked my normals and AO. Had some problems in Max while baking normals, so I had to switch to Xnormal. And they came out nicely :) Still have some cleaning to do in my AO, but I'm almost there. Comments are always welcome :)