I need to reblue a rifle barrel and receiver. I’m trying to decide what to use. I thought about having it cerakoted but I can cold blue it much cheaper. My questions are how does the cold blue hold up? Would I be better off just having cerakote applied? Thanks in advance for your help.

I wouldn't bother on a whole firearm. Cerra kote or parkerize.

Don't laugh, but I Oxpho Blued an entire Winchester M67 .22 rifle once on a dare. The rifle was gifted to a pre-teen whom we all knew would be hard as hell on the gun. Ten years later the thing still looks tasty. Also, I once used Oxpho Blue on a freshly installed barrel, because I was in a hurry to shoot it and promised myself I would re-do it with a rust bluing at the first opportunity. That opportunity never arose (ahem) and the thing looks good and has held up beautifully and frankly I'm inclined to leave it the heck alone now. Certainly not a substitute for a proper blue job of course, and I'll make no such claims, but sometimes things are counter-intuitively unexplainable.

I also like Oxpho Blue better than Permanent Blue. I found Oxpho a little more durable.

Since you are doing large items, you are going to find it a challenge to get the finish even and streak free. The odds are against you in that regard.

One way is multiple coats. Get the first one, degrease the metal, then use degreased steel wool to polish the coat, then reapply and you may find yourself doing that 10 more times before you have something "acceptable" to you.

A more durable finish is molybdenum. You can get it from John Norrels, they market theirs as moly resin. You will need an oven big enuff to fit your barreled receiver if you want to go that route

Birdsong black t just turned this for me in 5 weeks. $250 including scope rings. Based on my previous experience it wears really well.

Another vote for Oxpho... I pour boiling water on the metal to heat it just before applying. It works faster and wears well.