Chrome lining in the barrel.

[ontarget]

In an AR-15, how important is chrome lining? I have read about a thousand good reviews of the PSA Freedom Rifle kits but they aren't chrome lined. Big deal or don't sweat it? Any idea of barrel life on these? I am trying to assemble an M16-A2 clone.

 

[MTMilitiaman]

If you're assembling a clone then for the sake of accuracy, you'll want chrome lining. Because the military rifles are chrome lined.

If you're shooting high round counts you'll want chrome lining, or one of the newer metal treatment processes that accomplish the same thing. Some people will just chrome line the chamber, eliminate the forward assist, and other things to reduce cost. I don't agree with it, but I am not looking to get a $300 AR either.

 

[Charliefrank]

I am by no means close to an expert on this. I have heard many times over the years chrome lined bores will last longer and take more rounds through them. Personally I don't think most people shoot enough rounds to notice the difference. I once shot out the bore of a 220 swift, but I was pushing those bullets over 4000fps. Not to mention I bought it used. So who really knows how many rounds went through it. I personally put somewhere around 1000 rounds through it before it started developing problems.

 

[Sam1911]

What's the purpose of your build?

Are you trying to make a clone of a military rifle?

Are you trying to build a very accurate varmint or target rifle?

Are you likely to use this under really
harsh conditions and/or with questionable ammo?

 

[jmr40]

The chrome lining will resist corrosion and rust better if used in harsh conditions, probably a good idea for a combat rifle. A non-chrome lined barrel will likely be more accurate, probably better for a target rifle.

 

[ontarget]

Just building a range toy. I have wanted an A2 clone since I was in the Corps. Probably mostly use factory 55 or 62 grain FMJ.

 

[GBExpat]

The chrome lining will resist corrosion and rust better if used in harsh conditions, probably a good idea for a combat rifle. A non-chrome lined barrel will likely be more accurate, probably better for a target rifle.

This.

 

[Everready73]

A non chromed barrel will still last thousands of rounds. Past attention to the barrel steel and I would recommend 4150 over 4140. Many barrels that are not chromed are now nitride/melonite which also helps with durability and is a good option to chrome.

If you are looking for chrome check it Brownells retro line barrel assemblies or Green mountain Barrels. They are both good quality/value

 

[Varminterror]

For what I do and how I use my AR's, you can't GIVE me a chrome lined barrel.

 

[ontarget]

For what I do and how I use my AR's, you can't GIVE me a chrome lined barrel.

What exactly do you do? And how do you use your ARs?

 

[Llama Bob]

While it is possible to make an accurate chrome lined barrel, the process generally used on ARs rarely accomplishes that feat. I'll take mine without it.

 

[boom boom]

If you want to split the difference, get a nitrided one.

Here is an article on chromed bores by weaponsman
http://weaponsman.com/?p=12779

 

[RussellC]

The chrome lining will resist corrosion and rust better if used in harsh conditions, probably a good idea for a combat rifle. A non-chrome lined barrel will likely be more accurate, probably better for a target rifle.

Yes, I have always understood the non chrome barrel, everything else being equal will be the more accurate. I am not aware of chrome lined match barrels.

As others have said, advantage of chrome line would be in harsh military conditions, not accuracy.

Russellc

 

[boom boom]

Part of the problem with accuracy of chrome in the bore is that the rifle is bored larger to allow space for a surface of chrome plating. Depending on the skill level of the plater, variances in the thickness of plating can adversely affect accuracy. Your best barrel makers can have accuracy with a chromed bore on par with non-chrome. Generic no-names chrome plated barrels may or may not be accurate in a given barrel.

Nitrided barrels or stainless steel barrels seem to address the corrosion issue but chrome barrels still seem to last longer. Recently the longrunning AR15.com thread on battlefield Vegas had the owner mention that in their usage (a lot of full auto mag dumps here)--the chromed barrels seems to outlast the nitrided barrels-possibly because of the heat generated. Some military tests also seem to indicate the same thing--barrels are better protected by chrome than nitriding in rapid fire situations. Like anything, it is a cost benefit analysis depending on what you want from a barrel.

 

[ThomasT]

I don't know much about ARs but a buddy is about to buy or build one. He has the stripped lower already but found a deal on a new rifle and was asking about the chrome lined barrel. But I couldn't help him much. The only AR I have owned is a DPMS Panther like in the link below with 4140 ChromeMoly for a barrel. Is this a good barrel? I have owned this gun since right after Sandy hook and have only shot 80 rounds through it. I am not real worried about barrel life.

http://www.dpmsinc.com/PANTHER-CARBINE-16-RFA3_ep_212-1.html

 

[Everready73]

Yes, I have always understood the non chrome barrel, everything else being equal will be the more accurate. I am not aware of chrome lined match barrels.

As others have said, advantage of chrome line would be in harsh military conditions, not accuracy.

Russellc

If you did want a chrome lined barrel that is very accurate Criterion is the choice. Also check it done if Molons results on the Colt barrels he tested. They were very accurate for chrome lined

 

[lysanderxiii]

Part of the problem with accuracy of chrome in the bore is that the rifle is bored larger to allow space for a surface of chrome plating. Depending on the skill level of the plater, variances in the thickness of plating can adversely affect accuracy. Your best barrel makers can have accuracy with a chromed bore on par with non-chrome. Generic no-names chrome plated barrels may or may not be accurate in a given barrel.

Nitrided barrels or stainless steel barrels seem to address the corrosion issue but chrome barrels still seem to last longer. Recently the longrunning AR15.com thread on battlefield Vegas had the owner mention that in their usage (a lot of full auto mag dumps here)--the chromed barrels seems to outlast the nitrided barrels-possibly because of the heat generated. Some military tests also seem to indicate the same thing--barrels are better protected by chrome than nitriding in rapid fire situations. Like anything, it is a cost benefit analysis depending on what you want from a barrel.

Actually, the bore is bored to the same dimensions initially.

It is then electropolished to remove a thousandths of an inch or two then plated the same amount removed. Electropolishing is basically reverse plating and the amount removed can be controlled to better than ten-thousandths of an inch.

 

[M1key]

No one mentioned CL hammer forged. I have two FN built uppers, a 16 and a 20 inch and they shoot.

M