the best 50-cal rods I ever had were the Tipton 1-piece carbon ones, but they don't make them anymore. If you can find a used one...
I had sold 4 of them when I briefly got out of 50-cal shooting but now I'm back. Wish I had never sold them, they were SOLID (and $$).
I'm now using the Bore-Tech rods which look identical (except for the handle) to the Montana Extreme 50-cal rods I had which sucked balls because the coating started coming off very early. Sold the ME rods to a guy who didn't seem to care about the coating.
If the bore tech ones go south, I think I'm just getting the Dewey 2-piece nylon coated rods next time. Those Dewey never seem to disappoint. Don't know why they don't make a 1-piece, but for 50BMG a 2-piece should be OK
For patches, get the 2-1/4" (+/- 1/4") Butch's Triple Twill, there is no substitute.
For Bronze brush passes, I use Ed's Red that I make in 1-gallon batches every couple of years. I then patch it out.
Then for Butch's Bore Shine or Sweet's 7.62 passes or anything with Cu solvent in it, I use a nylon brush, then patch it out.
I then alternate Ed's red, patch out, BBS, patch out until the patches come out clean. With my Lilja barrel, I don't often if ever have to use strong Cu solvents or JB paste or anything like that.
I hate changing rod tips, which is Why I have 3 different rods (jag, nylon, bronze). Makes cleaning less annoying.
I know there's a contingent of 50-cal shooters who use SS brushes, but 50 steel barrels are same as smaller caliber, and nobody is using SS brushes on their 6.5 so I stay away from that.
Here's what it looks like clean: