I have a gun question.....

[Skysoldier]

Actually, I have several questions!

1. Are the internal barrels of firearm coated in any way, or is it just rifling in raw steel?

2. What is the best coating for a firearm? (I have been reading up on bluing, duracoat, and other stuff, but need better links!) (Hint, Hint!)

3. You can buy a drill bit at Home Depot that is TiN coated, but why aren't firearms TiN coated?

4. If I knew a process that could coat fireams with a DLC, would you be interested?

 

[CRSIII]

1. Raw steel.

2. Lots of choices, I like the sound TiN.

3. http://www.tincoat.net/coatings/tin.html?gclid=CIq14b-lo6ICFRRM5QodRE-oyw

4. Maybe.

 

[C & F Guns]

Some barrels are chrome lined.

 

[Skysoldier]

Some barrels are chrome lined.

The Army is doing research with coating 155mm Howitzer barrels with Tantalum. It lasts longer!

Don't ask me how I know this!

 

[ShadeWPI]

Actually, I have several questions!

1. Are the internal barrels of firearm coated in any way, or is it just rifling in raw steel?

2. What is the best coating for a firearm? (I have been reading up on bluing, duracoat, and other stuff, but need better links!) (Hint, Hint!)

3. You can buy a drill bit at Home Depot that is TiN coated, but why aren't firearms TiN coated?

4. If I knew a process that could coat fireams with a DLC, would you be interested?

1. Are the internal barrels of firearm coated in any way, or is it just rifling in raw steel?
Usually the interior of the barrel is raw metal (Moly-Chrome Steel, Stainless Steel, Carbon-Steel, etc) because this is easier and maintaining dimensional accuracy of the bore is critical AND wear will quickly destroy any of the normal coatings. Most coatings are intended to provide corrossion resistance rather than wear resistance and for the bore, this typically just means a light sheen of oil.

All that said, new military rifles often have Hard Chrome chambers and barrels, so there are some coatings on the interior of barrels.

2. What is the best coating for a firearm? (I have been reading up on bluing, duracoat, and other stuff, but need better links!) (Hint, Hint!)

This will depend on the firearm, application and need. For classic military firearms, Bluing and Manganese Phosephate (Parkerizing) are typically the best. Duracoat and Cerakote, which are ceramic impregnated epoxy finishes offer more colors than other finishes, but they are surface coats, so they can wear off and they alter dimensions (though slightly) - they are not good for the inside of the barrel.

3. You can buy a drill bit at Home Depot that is TiN coated, but why aren't firearms TiN coated?

I'd have to check on the adhesion properties between Titanium-Nitride and lead, copper and brass, but some companies have started offering Titanium-Nitride coated bolt carrier groups, but no barrels yet. This might be due to adhesion with copper or lead OR difficulties maintaining dimensional accuracy, or these barrels might be on their way in the future.

4. If I knew a process that could coat fireams with a DLC, would you be interested?

Interested, yes, but I'd need to know a lot more about the process, it's affect on the temper of the barrel steel? , dimentinoal stability, thermal stability, wear resistance, feature-shape maintance, adhesion with copper and lead.

 

[01SVTvert]

Some can be gas nitrided or in Glock's case tennifered. Not really a coating but a hardening process which will result in decreased wear and increased corrosion resistance.

For TiN I am assuming most do not want a gold colored gun and most coatings are applied to resist corrosion rather than hardening as other processes such as tempering and the two above are used to improve durability so hardening is not an issue. Also, since TiN can be stripped I would wonder what a bullet being sent down the barrel would do to it.

 

[Skysoldier]

The TiN question was just for exterior applications. I know it can't be used for the bore because it will react to the corrosive gases.

But Tantalum and DLC coatings especially would add a great benefit.

The problem with DLC has always been the heating of the substrate, which would affect the temper of the steel, but new technologies are being developed now
that involve Plasma Immersion Ion Implantation that could solve that problem.

Looks like I have a lot to learn, and a lot more research ahead.

I appreciate the feedback!