Barrel and Action Nitride Coating

[Mr. Magoo]

If you polish the steel to mirror-like finish, melonited surface comes out like Colt royal blue finish.

Oooh. Perfect.

 

[Mr. Magoo]

That's another debate. Brazed handle on the bolt, I will have to ask the provider. The action, I would not hesitate to do one of my 700s. Defiance and others have no problem getting theirs melonited, while others are adverse to it.

Always two sides, take your pick.

What temperature are we looking at for the meloniting process?

700 degrees is the area where a chromolly type steel is normalized and stress releived. I think that's a good thing, as not only does it keep residual stresses left in the metal (from machining) from making the parts move as temp changes, but also from cracking in parts that have high cyclical loads and areas where there may be stress risers due to shape.

 

[idcwby]

Has anyone nitrided the new 400MODBB steel from Bartlein?

 

[bamban]

What temperature are we looking at for the meloniting process?

700 degrees is the area where a chromolly type steel is normalized and stress releived. I think that's a good thing, as not only does it keep residual stresses left in the metal (from machining) from making the parts move as temp changes, but also from cracking in parts that have high cyclical loads and areas where there may be stress risers due to shape.

About 1000

 

[bamban]

Oooh. Perfect.

Expand picture you will see that the gas block journals are shinier than would end up inside the handguard. I slightly polish the journal and the section going towards the muzzle

You should have at least one in the shop to play with LOL!

How about 19? Just unwrapped them.

 

[CA48]

Thanks for the responses. So are the custom bolt actions that come nitrided heat treated before or after the nitriding process?

 

[manitou]

More info: Ted Karagias at ARC warns against nitriding his actions because it negatively affects the heat treat.

There are some makers that nitride them when they build them. One would assume they give consideration on this in with the heat treat as these are some pretty good actions bu respectable manufacterers.

 

[Gregg K. Price]

Has anyone nitrided the new 400MODBB steel from Bartlein?

I've

 

[Mr. Magoo]

Thanks for the responses. So are the custom bolt actions that come nitrided heat treated before or after the nitriding process?

If they're nitrided, I'm gonna hazzard a guess they're not heat treated.

I'm not sure what alot of modern actions are made of, but the old ones like the rem 700s were chrome-molybdenum steel in the annealed (non- heat treated state)

There are modern steels out there now that have better tensile strength without having to be heat treated.

Because of the way heat treating chrom-moly distorts and ruins the surface finish, it has to be machined and finished after. There are steels that do keep dimensional tolerances through heat treating but it would still ruin the finish

 

[shortgrass]

If they're nitrided, I'm gonna hazzard a guess they're not heat treated.

I'm not sure what alot of modern actions are made of, but the old ones like the rem 700s were chrome-molybdenum steel in the annealed (non- heat treated state)

There are modern steels out there now that have better tensile strength without having to be heat treated.

Because of the way heat treating chrom-moly distorts and ruins the surface finish, it has to be machined and finished after. There are steels that do keep dimensional tolerances through heat treating but it would still ruin the finish

Salt bath nitride treatment is done after heat treating. Applies to CM and 416SS. Nitriding is an "add on", NOT a substitute for heat threating. Remington 700s. both CM and SS, are machined from pre-heat treated steel. It arrives/arrived at the Remington factory heat treated , probably from the mill it was purchased from. Just because a Rem 700 action can be cut with a file doesn't mean that it's not been heat treated. It has been 'hardened and tempered'. As a machinist (and I began machining in 1974) we have been cutting 4140PH (pre hardened) since it became available. Hard on HS tooling? Yes! But we machined precision parts from it all of the time! Now, most all tooling is of carbide, which will withstand the heat. If you machined an action from annealed steel, and then heat treated it, it would warp because of the differing thicknesses that are found across the action. The loading port side being thinner than the opposite side. Deflection (warpage) has always been a problem when heat treating, whether it be 'case hardening' low carbon steel or 'through hardening' like 4140 and other modern alloys are hardened. As an after note, nitriding can not be done to low carbon, case hardened steels, only on modern, through hardening alloys.

 

[bamban]

What temperature are we looking at for the meloniting process?

@Mr. Magoo

Here is the QA sheet from the last batch I sent.

 

[parshal]

Is ok to black nitride factory actions like a Rem 700 plus the bolt? Just curious if the high temps from the process change the metallurgy or original heat treat and weaken it?

I did and worked great.

 

[jbronner13]

I did some reading into this a while back and decided in custom builds it seems like a good idea to have the barrel and action nitrided to increase longevity. I just sent off two rifles to Wright Armory in Mesa, AZ and the barrels, actions and internals/small parts are all getting nitrided. I am likely going to do the same for 2-3 more rifles I am having built but want to see how these two perform first. I am having them nitride a 416 SS and a 4140 CM. I think if you can get a 4140 CM in the white and have it nitrided it may come out with a matte blue type finish, I will send some pics when I get my stuff back.

Everything I read says longer life of service, minimal to no effect on accuracy and easier cleaning.

If you talk to James at Northland Shooters Supply, they will nitride criterion pre-fit barrels for you.

Wright is no longer offering the DLC quick lube coating for bolts as an FYI.

 

[CA48]

Is

I did and worked great.

Is your bolt handle original and soildered on or tig welded?