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Can a barrel which has salt bath nitride treatment be rechambered?

Not if you don't cut the whole chamber off and get below the case hardening. Why??

I want to rework my .257SLR.

I was told by Scott Null who built my 338 RUM VLRR, that once nitrided nothing can be done to the barrel. His son who marks the cartridge designation of the barrel (lightly) goes through one carbide router bit per barrel.

The "beast":

Wow! Some times the truth is bad news. My reamer is high speed steel so that is out. The rifle already has a new barrel (6.5SLR), I was just going to make another for when this one is no longer accurate.

By the way, your beautiful rifle and my other 6.5mm use the same case, sorta. What bullet do you use?

I'm not known for being the sharpest knife in the drawer so feel free to point out something I missed but since you can't change anything after coating, he has to know where the barrel will headspace before he sends it out so he would also know exactly where to engrave it.

Why wouldn't he mark the barrel before he has the coating done?

I engrave mine after with my New Hermes diamond scribe. Melonite, Isonite, or nitride is a case hardening. It is about .0005 deep. It is about 60+ Rockwell, but get below it and it machines just like it did originally.

Makes sense Butch but I am still curious why it isn't done before sending it out? Are you looking for a color contrast by cutting through the coating?

Dan, I said nothing about not finishing it first. I took it that he wanted to know if he could rechamber it.

OK Butch, yes the OP did ask about rechambering and then it was mentioned that someone wears out his tooling engraving the caliber after coating. When I asked why would someone not engrave first and then have it coated. I saw your post:



I guess I somehow misunderstood the "after" part to mean after coating. That's why I hate email/text/forum posts - nothing like a face to face conversation to be sure we are on the same page.

Dan

Dan,
Remember, it is not a coating. It is in simpler terms a case hardening process. No buildup. I have recrowned one, but have not had any need to rechamber. I personally think it would be time for another barrel.

LOL

Lead Sled is a good way to ruin a scope and stock. They are also hard to use when you are hunting.

Butch, this is not a hunting rifle as it weighs 20+ pounds. The lead sled can wreck a stock if misused, too much weight on a light hard kicker with a stock of the wrong wood and grain pattern. As for scopes, I think a $2400 IOR will not come apart.
I only have 20 pounds in the bags and the sled is on a padded mat so it slides back about 3".

Cheap stocks and scopes could fail but I don't own any cheap scopes or fragile stocks that I need a sled to shoot.

It is a 1000-2000 yard gong ringer and that's all. It does that very well.

Nitriding bears no relationship to case hardening as the latter is very fragile and can be destroyed with 4 ought steel wool.

Be looking forward to seeing you boys 1000 yards guns.

I do have another that is only 7 years younger than me and I shoot it off plain old bags as it is only a 300 H&H. Checkered by Roy's shop and went to Perry twice.

best to you and yours, Larry

You have no idea what case hardening is, do you?

People tend to get color case hardening and case hardening confused.

Case hardening normally penatrates up to .040 but it can be pushed much deeper. http://www.burlingtoneng.com/case_hardening.html

With the MELONITE Nitrocarburizing Process the nitride layer is composed of two principle zones. Zone 1, called the compound or "white" layer, extends to a case depth of ~0.0004" to 0.0008". The compound layer is porous, which lends to the lubricity of the finish, and hard (~700HV to 1600HV). Zone 2, called the diffusion zone, extends to a case depth of ~.004" to 0.008". http://www.burlingtoneng.com/melonite.html

With color case hardening the colors will fade on exposure to direct sunlight over an extended time period and the color can be taken off with courser steel wool but the depth of hardness is a couple of thousands deep. http://www.doublegunshop.com/doublegunjournal_v7i4_9.htm

Thats funny, whenever I need to get through something that was case hardened I needed a special bit. I guess next time I will remove it with steel wool and just use something cheap instead of a good carbide.

Im sorry if I sound lost, I dont frequent to many of the actual topics, but who is Larry and why does he think he knows as much as he does?

I have parts that are case hardened, nitrided and melonited (to be clear not all three on one part) and I would not consider any of them fragile. I had a burr in an AR-15 chamber that had been melonited and the manufacture replaced it rather than mess with it.

Sure doesn't write as though he does, does he ?

GTC

I have to call your BS on that.

What are the dimensions of the "2000 yard gong"?