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Pick your favorite barrel manufacturer and they will have it done for you .

I would mention what you want up front as far as Chrome Bore lining prior to just purchasing

a barrel and having it done after .

I picked this up off the Net .


Manufacturers are doing something relatively new, they are putting a chrome wash in the bores of some barrels. It appears that they are in magnum calibers mainly. Before USRAC (Winchester) shut down they were doing this with the WSM barrels. It appears that Browning is doing the same thing.

Latest gun gossip is that the New FN bores are chrome washed. Also the new “Winchester Repeating Arms” do to come on the market this summer some time will be using the same process in some of their barrels.

Why is this important?

Because if your not aware of it your reamers will take beating. One reamer maker told me that he is selling carbide throating reamers regularly now, he said that was unheard of just a couple of years ago. Reamer rental agencies are aware of this problem as well and will be forced to resharpen reamers used in chrome bores, be prepared to pay for the resharpening if you make this mistake.

The worst part of this little bit of information is that there is no clear list of calibers or models in which the manufacturers are using chrome.

The chrome lining would play hell on a chamber reamer.

Chrome 'wash' ? Can you define that ? Sometimes a 'wash' means a very thin layer of plating. I have a number of chrome plated barrels but I know nothing about how thick it is.
The chrome of course should be hard chrome , not soft or decorative chrome.

I know it's only a few thousands thick " Wash " is simply a loosely used terminology .

Hard Chrome Not decorative Best I can do is something like this link .

http://www.finishing.com/faqs/chrome.html

The ways on Machinery beds and rails are generally Hard Chromed Lathes Mills things like that .

quote:

Manufacturers are doing something relatively new, they are putting a chrome wash in the bores of some barrels.

The worst part of this little bit of information is that there is no clear list of calibers or models in which the manufacturers are using chrome.

"Relatively new!?! Chrome palting bores has been done for decades.

It cabe done on any barrel, so I don't see that ch"calibers" have to do with it?

On thing not mentioned here is that accuracy suffers. THe plating is porous and does not have as slick and consistent of a bore as do unplated bores.

As has been mentioned, chromed bored doo not play well with HSS reamers

Just out of curiosity...do any makers of button-rifled barrels do chrome plating? If they do, I am surprised.

Chrome (like any other metal one might put in there) would have a measurable "thickness", so if a bore was drilled, rifled, then plated, one would think it would be smaller diameter inside than a non-plated bore made with the same button.

With cut-rifled barrels, it is fairly easy to set the cutter to allow a deeper cut. The plating then replaces the extra metal cut away...at least in theory it does, if done carefully enough.

The thing that leaps to my mind is that manufacturers who do not cut rifle their barrels but DO provide chrome-plating, probably either don't guarantee rifle accuracy, or do not offer unplated barrels as an option. If they did, and wanted barrel dimensions to be "right", they'd have to have different rifling buttons or different forging mandrels for both the plated and unplated barrels of each bore diameter, wouldn't they?

If you don't care about accuracy then by all means by chrome plated barrels.

Chroming bores was the answer to barrels wearing out from the high rates of fire of military weapons that could not cleaned properly due to mission requirements or the attitudes of non-gunnut troopers..

quote:

Originally posted by Grenadier:
Just a comment about accuracy - Issue M16s and M4s regularly achieve 1-2 minutes of accuracy with open sights. I would imagine that any loss in accuracy due to chrome lining is insignificant. Perhaps it would be enough to matter on a serious benchrest or target rifle but not on a hunting arm.

My main reason for asking is that I would like to get the benefit of corrosion resistance.

And issue M-16s & M-4s are NOT available with unplated bores...so the barrels are obviously reamed/rifled or forged allowing for the final plating step. If you already have an unplated barrel, it likely wasn't.

Still, if you want to plate your bore, you might try locating the plating service of Marker Machine Company. They have been "black-chroming" bores for more than 50 years that I know of....at least I assume they are still doing it.

If you can't find such a service, e-mail the U.S. NRA technical service. They can tell you of providers.

I have assembled several AR-15's with chrome lined chambers and bores and all have been capable of minute of angle. Shaw is one of the big suppliers of chrome lined as is Wilson. Perhaps if you call them, they offer the service for their other barrels.

To the best of my knowledge, it is not the bore, but the chamber that really matters in regard to "chroming". Early in the Vietnam war is was found that M16s chambering a round overnight in the field had the case stick in the chamber. Chrome plating stopped this. The best solution in a sporting rifle is just to go with a stainless barrel. Stainless is smoother then CM steel and thus stainless barrels are theoretically more accurate anyway. How much accuracy this translates to in reality I have no idea.

Marc ; I simply copied that and posted that information .No Chroming bores isn't new .

I believe that particular article was referencing Commercial manufactures rather than Military ones .

As far as accuracy goes ( Don't let anyone BS you on that )

My Bushmasters are all EVERY SINGLE ONE OF THEM ( #3 ) sub .5 MOA with hand loads !.

Two of them will go .285" if I do my part ( Scoped with a 8X and 10X ) .

one uses H335 the other prefers BLC-2 my 3 Rd rifle will digest almost anything factory or hand

loads and stay under an inch . That's #1 Fouler and #3 #5 round groups for a total of #15 rounds

score . Shot with in 20 minutes .

NONE of my Bolt guns will do that NONE !. My 7 RM Mauser will print #5 a quarter will

cover using a 154 - 160 grain boat tail some times .It's not chrome lined !.

As I suggested speaking to the barrel manufacturer about Chrome lining prior to purchasing the

barrel would be advisable . As AC stated it does build a few thousands which could be critical

or not . I haven't a clue on that side of the equation . Here is another copied article .



One needs to speak to the Barrel manufactures as their the EXPERTS . Check out places near you or E mail

them with Questions concerning pros and cons .

http://efinishing.com/jobshops...mdocs=25&minscore=25

Industrial Hard Chrome Plating

hard chrome machine plating Our quality-driven industrial hard chrome plating services have many different applications:

* Restoring worn parts to their original size and shape.
* Protecting the surfaces of new parts to help them resist abrasion and extend wear life.
* Protecting parts from corrosion from different environmental factors and abrasion on their wear surfaces.
* Restoring worn parts to like new tolerances

What makes hard chrome plating such a perfect choice for these applications?

* Hard chrome is extremely hard, measuring 68-72 Rockwell, which means a longer life for your part.
* Hard chrome has the versatility to be used to re-size, restore and repair parts and also build certain types of parts from scratch.
* Hard chrome will protect your parts against corrosion and wear in tough environments.
* Hard chrome is known for its adhesive properties, which are greater than 10,000 psi.
* Hard chrome works well with a variety of base metals, including steel, stainless steel and cast iron.
* Hard chrome is porous, and therefore has excellent lubricating value, making it perfect for hydraulic applications

One thing to consider is that the really effective copper solvents like Sweets and Barnes may also attack the chrome lining of the barrel. Military weapons seldom if ever see much more then CLP or maybe Hoppes purchased at the PX.