Electropolishing Barrels

[Pax]

Google has turned up nothing but outdated and conflicting results. I trust the conglomerate of decades of expertise here more than anywhere else in the world.

I have a short 416R 300 BLK barrel thats been sitting for months. Finally getting this gun together. Because I live in south Texas, the taint of the world, even this stainless barrel has developed light surface oxidation sitting in a box in an air conditioned room.

I am interested in electropolishing the outside surface. I understand it could be blasted with fine aluminum oxide to achieve a similar effect, but Im always interested in things I can do myself. One concern is that it may make the surface too smooth for optimal adhesion of CeraKote. I do not intend to regularly remove my handguard to reoil the outside of the barrel to prevent rust, so unfortunately CeraKote becomes necessary. I have no idea why anyone would ever settle in this swamp of a city. Any CeraKoters care to weigh in on coaring extremely smooth surfaces? Supposedly electropolishing makes it significantly less likely to ever corrode again by removing iron from the surface. We shall see. I intend to seal the bore at the chamber throat and muzzle crown with silicone gasket maker. Have plenty on hand, its easy to remove and theoretically should be unaffected by the electrolyte solution. This will also polish the chamber, feed ramps, and lugs.

I have heard mainly skeptical/critical responses to electropolishing bores, and it just doesnt seem necessary to me considering how the bore will be scraped clean by brushes and reoiled with a regular firing schedule. Any rust in there wont last long. Additionally, while accuracy is not a major concern on this weapon since its intended maximum range is a couple hundred yards, it is always preferable when possible to accurize all weapons, and the potential for electropolishing to debur the rifling lands to the point that they no longer impart a stabilizing spin is bad juju. There are simply too many variables that appear so untested as to be unknowable: the electrolyte composition, voltage, duration, etc. To make matters worse the difference were talking about is so minute as to be unmeasurable with any tool Id ever own. Long story short, Id prefer to leave the bore alone.

I presume this wouldnt affect the barrels structural integrity in any way. But. Thats why Im here. Correct me if Im wrong. Id rather not destroy a barrel.

If it matters, I also eventually intend to have Marvin Pitts dimple this.

So. Sorry for the novel. Many factors to consider... If you had a 416R barrel with minor oxidation, how would you refinish it? Just shell out for media blasting and coating? Anybody have any experience with electropolished parts they feel would be relevant? Thanks.

[MegademiC]

No, degreaser, followed by acid dip followed immediately by a rinse and cerakote.
Why would you electropolish? Buff it, abraded it, soak it in coke... electropolish?
Or bead blast the finish.
If your really feeling froggy, you could try your hand at electroplating it.


Edit , what solution did you plan to use? I'd leaving it to a pro, difinately do not electropolish if you don't know what your doing.

[Pax]

Id rather have a very uniform finish across the entire part. Electropolishing offers this. No abrasive does. I could get it pretty close to uniformly clean with fine sandpaper or mild abrasive compounds and buffing, and Ill admit its uniformity wont matter much after dimpling, CeraKoting and then being covered with a handguard... but if a simple, DIY electropolishing setup is an easier way to produce a more perfect surface finish... why not?

Edit: unknown on solution. Thought Id spitball a bit here and see if anything comes up. Ive seen excellent results with DIY setups on old motorcycle parts, but of course thats gonna be a very different substrate.

[MegademiC]

abrasives do offer uniform finish, if used properly.

Soak it in coke until the rust is gone and call it a day. I predict electropolishing will not end well for you.

Or have someone sand blast it, or stick it in a tumbler. There are a lot of ways to get what you want. Electropolish img is probably one of the least diy methods.

Lastly, you generally want a rough surface to enhance adhesion of paints. Electropolishing offers a smooth surface, not what you want.

[GH41]

"I predict electropolishing will not end well for you"

He may as well just throw in a bucket of acid. What will this electropolishing do to the extension/barrel relationship??

[Todd.K]

Why waste your time? If the barrel is going to get dimpled it will cut off most of your work. Also a good rough blast is preferred for cerakote.

I would just oil it for now. Then get it cerakoted after you get around to dimpling. After that you won't have to worry about it at all.

[Hkbeltfed]

If it's not bad, just use a large pink pencil eraser.

[Pax]

Why waste your time? If the barrel is going to get dimpled it will cut off most of your work. Also a good rough blast is preferred for cerakote.

I would just oil it for now. Then get it cerakoted after you get around to dimpling. After that you won't have to worry about it at all.

Fair point. I may be reasonable for once and listen. I get fairly perfectionist. That and the ease/cheapness of creating my own setup are the main factors attracting me to it.

Appreciate the input guys. Im definitely going to play around with an electropolishing setup just because its so cheap and easy- but Ill also definitely experiment with cheaper, less important parts first.

As far as the barrel extension... only experience could tell for sure, but I imagine an electropolished chamber and reed ramps would be a good thing... People shell out good money to have theirs polished or NiB plated already...

[GH41]

"As far as the barrel extension... only experience could tell for sure, but I imagine an electropolished chamber and reed ramps would be a good thing... People shell out good money to have theirs polished or NiB plated already"

What people pay to have a properly chambered barrel and feed ramps polished?? Do you have any idea what electropolishing actually does? It erodes the metal's surface. Like I said earlier... No different than throwing the parts in a bucket of acid. I doesn't polish anything.

[Pax]

"As far as the barrel extension... only experience could tell for sure, but I imagine an electropolished chamber and reed ramps would be a good thing... People shell out good money to have theirs polished or NiB plated already"

What people pay to have a properly chambered barrel and feed ramps polished?? Do you have any idea what electropolishing actually does? It erodes the metal's surface. Like I said earlier... No different than throwing the parts in a bucket of acid. I doesn't polish anything.

Ok.

I somehow doubt that any reasonably attentive person would leave the part in long enough to cause significant enough erosion to risk casing failure or any reliability issues, were dealing with micrometers here at most as far as I can tell... as in 0.0005" ish.

But ok.

And... Polished feed ramps at the least if not chambers have been pretty normal for decades. Usually in handguns, but definitely also present in carbines. See Fail Zeros NiB extensions. Its an area people are focusing on. Not necessary or game changing, agreed. Any gun *should* run without fancy surface treatments... But thats definitely a thing.